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openmedialibrary_platform/Darwin/lib/python2.7/site-packages/sqlalchemy/sql/compiler.py

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Open Media Library Platform
2013-10-11 17:28:32 +00:00
# sql/compiler.py
# Copyright (C) 2005-2014 the SQLAlchemy authors and contributors <see AUTHORS file>
#
# This module is part of SQLAlchemy and is released under
# the MIT License: http://www.opensource.org/licenses/mit-license.php
"""Base SQL and DDL compiler implementations.
Classes provided include:
:class:`.compiler.SQLCompiler` - renders SQL
strings
:class:`.compiler.DDLCompiler` - renders DDL
(data definition language) strings
:class:`.compiler.GenericTypeCompiler` - renders
type specification strings.
To generate user-defined SQL strings, see
:doc:`/ext/compiler`.
"""
import re
from . import schema, sqltypes, operators, functions, \
util as sql_util, visitors, elements, selectable, base
from .. import util, exc
import decimal
import itertools
import operator
RESERVED_WORDS = set([
'all', 'analyse', 'analyze', 'and', 'any', 'array',
'as', 'asc', 'asymmetric', 'authorization', 'between',
'binary', 'both', 'case', 'cast', 'check', 'collate',
'column', 'constraint', 'create', 'cross', 'current_date',
'current_role', 'current_time', 'current_timestamp',
'current_user', 'default', 'deferrable', 'desc',
'distinct', 'do', 'else', 'end', 'except', 'false',
'for', 'foreign', 'freeze', 'from', 'full', 'grant',
'group', 'having', 'ilike', 'in', 'initially', 'inner',
'intersect', 'into', 'is', 'isnull', 'join', 'leading',
'left', 'like', 'limit', 'localtime', 'localtimestamp',
'natural', 'new', 'not', 'notnull', 'null', 'off', 'offset',
'old', 'on', 'only', 'or', 'order', 'outer', 'overlaps',
'placing', 'primary', 'references', 'right', 'select',
'session_user', 'set', 'similar', 'some', 'symmetric', 'table',
'then', 'to', 'trailing', 'true', 'union', 'unique', 'user',
'using', 'verbose', 'when', 'where'])
LEGAL_CHARACTERS = re.compile(r'^[A-Z0-9_$]+$', re.I)
ILLEGAL_INITIAL_CHARACTERS = set([str(x) for x in range(0, 10)]).union(['$'])
BIND_PARAMS = re.compile(r'(?<![:\w\$\x5c]):([\w\$]+)(?![:\w\$])', re.UNICODE)
BIND_PARAMS_ESC = re.compile(r'\x5c(:[\w\$]+)(?![:\w\$])', re.UNICODE)
BIND_TEMPLATES = {
'pyformat': "%%(%(name)s)s",
'qmark': "?",
'format': "%%s",
'numeric': ":[_POSITION]",
'named': ":%(name)s"
}
REQUIRED = util.symbol('REQUIRED', """
Placeholder for the value within a :class:`.BindParameter`
which is required to be present when the statement is passed
to :meth:`.Connection.execute`.
This symbol is typically used when a :func:`.expression.insert`
or :func:`.expression.update` statement is compiled without parameter
values present.
""")
OPERATORS = {
# binary
operators.and_: ' AND ',
operators.or_: ' OR ',
operators.add: ' + ',
operators.mul: ' * ',
operators.sub: ' - ',
operators.div: ' / ',
operators.mod: ' % ',
operators.truediv: ' / ',
operators.neg: '-',
operators.lt: ' < ',
operators.le: ' <= ',
operators.ne: ' != ',
operators.gt: ' > ',
operators.ge: ' >= ',
operators.eq: ' = ',
operators.concat_op: ' || ',
operators.between_op: ' BETWEEN ',
operators.match_op: ' MATCH ',
operators.in_op: ' IN ',
operators.notin_op: ' NOT IN ',
operators.comma_op: ', ',
operators.from_: ' FROM ',
operators.as_: ' AS ',
operators.is_: ' IS ',
operators.isnot: ' IS NOT ',
operators.collate: ' COLLATE ',
# unary
operators.exists: 'EXISTS ',
operators.distinct_op: 'DISTINCT ',
operators.inv: 'NOT ',
# modifiers
operators.desc_op: ' DESC',
operators.asc_op: ' ASC',
operators.nullsfirst_op: ' NULLS FIRST',
operators.nullslast_op: ' NULLS LAST',
}
FUNCTIONS = {
functions.coalesce: 'coalesce%(expr)s',
functions.current_date: 'CURRENT_DATE',
functions.current_time: 'CURRENT_TIME',
functions.current_timestamp: 'CURRENT_TIMESTAMP',
functions.current_user: 'CURRENT_USER',
functions.localtime: 'LOCALTIME',
functions.localtimestamp: 'LOCALTIMESTAMP',
functions.random: 'random%(expr)s',
functions.sysdate: 'sysdate',
functions.session_user: 'SESSION_USER',
functions.user: 'USER'
}
EXTRACT_MAP = {
'month': 'month',
'day': 'day',
'year': 'year',
'second': 'second',
'hour': 'hour',
'doy': 'doy',
'minute': 'minute',
'quarter': 'quarter',
'dow': 'dow',
'week': 'week',
'epoch': 'epoch',
'milliseconds': 'milliseconds',
'microseconds': 'microseconds',
'timezone_hour': 'timezone_hour',
'timezone_minute': 'timezone_minute'
}
COMPOUND_KEYWORDS = {
selectable.CompoundSelect.UNION: 'UNION',
selectable.CompoundSelect.UNION_ALL: 'UNION ALL',
selectable.CompoundSelect.EXCEPT: 'EXCEPT',
selectable.CompoundSelect.EXCEPT_ALL: 'EXCEPT ALL',
selectable.CompoundSelect.INTERSECT: 'INTERSECT',
selectable.CompoundSelect.INTERSECT_ALL: 'INTERSECT ALL'
}
class Compiled(object):
"""Represent a compiled SQL or DDL expression.
The ``__str__`` method of the ``Compiled`` object should produce
the actual text of the statement. ``Compiled`` objects are
specific to their underlying database dialect, and also may
or may not be specific to the columns referenced within a
particular set of bind parameters. In no case should the
``Compiled`` object be dependent on the actual values of those
bind parameters, even though it may reference those values as
defaults.
"""
def __init__(self, dialect, statement, bind=None,
compile_kwargs=util.immutabledict()):
"""Construct a new ``Compiled`` object.
:param dialect: ``Dialect`` to compile against.
:param statement: ``ClauseElement`` to be compiled.
:param bind: Optional Engine or Connection to compile this
statement against.
:param compile_kwargs: additional kwargs that will be
passed to the initial call to :meth:`.Compiled.process`.
.. versionadded:: 0.8
"""
self.dialect = dialect
self.bind = bind
if statement is not None:
self.statement = statement
self.can_execute = statement.supports_execution
self.string = self.process(self.statement, **compile_kwargs)
@util.deprecated("0.7", ":class:`.Compiled` objects now compile "
"within the constructor.")
def compile(self):
"""Produce the internal string representation of this element.
"""
pass
def _execute_on_connection(self, connection, multiparams, params):
return connection._execute_compiled(self, multiparams, params)
@property
def sql_compiler(self):
"""Return a Compiled that is capable of processing SQL expressions.
If this compiler is one, it would likely just return 'self'.
"""
raise NotImplementedError()
def process(self, obj, **kwargs):
return obj._compiler_dispatch(self, **kwargs)
def __str__(self):
"""Return the string text of the generated SQL or DDL."""
return self.string or ''
def construct_params(self, params=None):
"""Return the bind params for this compiled object.
:param params: a dict of string/object pairs whose values will
override bind values compiled in to the
statement.
"""
raise NotImplementedError()
@property
def params(self):
"""Return the bind params for this compiled object."""
return self.construct_params()
def execute(self, *multiparams, **params):
"""Execute this compiled object."""
e = self.bind
if e is None:
raise exc.UnboundExecutionError(
"This Compiled object is not bound to any Engine "
"or Connection.")
return e._execute_compiled(self, multiparams, params)
def scalar(self, *multiparams, **params):
"""Execute this compiled object and return the result's
scalar value."""
return self.execute(*multiparams, **params).scalar()
class TypeCompiler(object):
"""Produces DDL specification for TypeEngine objects."""
def __init__(self, dialect):
self.dialect = dialect
def process(self, type_):
return type_._compiler_dispatch(self)
class _CompileLabel(visitors.Visitable):
"""lightweight label object which acts as an expression.Label."""
__visit_name__ = 'label'
__slots__ = 'element', 'name'
def __init__(self, col, name, alt_names=()):
self.element = col
self.name = name
self._alt_names = (col,) + alt_names
@property
def proxy_set(self):
return self.element.proxy_set
@property
def type(self):
return self.element.type
class SQLCompiler(Compiled):
"""Default implementation of Compiled.
Compiles ClauseElements into SQL strings. Uses a similar visit
paradigm as visitors.ClauseVisitor but implements its own traversal.
"""
extract_map = EXTRACT_MAP
compound_keywords = COMPOUND_KEYWORDS
isdelete = isinsert = isupdate = False
"""class-level defaults which can be set at the instance
level to define if this Compiled instance represents
INSERT/UPDATE/DELETE
"""
returning = None
"""holds the "returning" collection of columns if
the statement is CRUD and defines returning columns
either implicitly or explicitly
"""
returning_precedes_values = False
"""set to True classwide to generate RETURNING
clauses before the VALUES or WHERE clause (i.e. MSSQL)
"""
render_table_with_column_in_update_from = False
"""set to True classwide to indicate the SET clause
in a multi-table UPDATE statement should qualify
columns with the table name (i.e. MySQL only)
"""
ansi_bind_rules = False
"""SQL 92 doesn't allow bind parameters to be used
in the columns clause of a SELECT, nor does it allow
ambiguous expressions like "? = ?". A compiler
subclass can set this flag to False if the target
driver/DB enforces this
"""
def __init__(self, dialect, statement, column_keys=None,
inline=False, **kwargs):
"""Construct a new ``DefaultCompiler`` object.
dialect
Dialect to be used
statement
ClauseElement to be compiled
column_keys
a list of column names to be compiled into an INSERT or UPDATE
statement.
"""
self.column_keys = column_keys
# compile INSERT/UPDATE defaults/sequences inlined (no pre-
# execute)
self.inline = inline or getattr(statement, 'inline', False)
# a dictionary of bind parameter keys to BindParameter
# instances.
self.binds = {}
# a dictionary of BindParameter instances to "compiled" names
# that are actually present in the generated SQL
self.bind_names = util.column_dict()
# stack which keeps track of nested SELECT statements
self.stack = []
# relates label names in the final SQL to a tuple of local
# column/label name, ColumnElement object (if any) and
# TypeEngine. ResultProxy uses this for type processing and
# column targeting
self.result_map = {}
# true if the paramstyle is positional
self.positional = dialect.positional
if self.positional:
self.positiontup = []
self.bindtemplate = BIND_TEMPLATES[dialect.paramstyle]
self.ctes = None
# an IdentifierPreparer that formats the quoting of identifiers
self.preparer = dialect.identifier_preparer
self.label_length = dialect.label_length \
or dialect.max_identifier_length
# a map which tracks "anonymous" identifiers that are created on
# the fly here
self.anon_map = util.PopulateDict(self._process_anon)
# a map which tracks "truncated" names based on
# dialect.label_length or dialect.max_identifier_length
self.truncated_names = {}
Compiled.__init__(self, dialect, statement, **kwargs)
if self.positional and dialect.paramstyle == 'numeric':
self._apply_numbered_params()
@util.memoized_instancemethod
def _init_cte_state(self):
"""Initialize collections related to CTEs only if
a CTE is located, to save on the overhead of
these collections otherwise.
"""
# collect CTEs to tack on top of a SELECT
self.ctes = util.OrderedDict()
self.ctes_by_name = {}
self.ctes_recursive = False
if self.positional:
self.cte_positional = []
def _apply_numbered_params(self):
poscount = itertools.count(1)
self.string = re.sub(
r'\[_POSITION\]',
lambda m: str(util.next(poscount)),
self.string)
@util.memoized_property
def _bind_processors(self):
return dict(
(key, value) for key, value in
((self.bind_names[bindparam],
bindparam.type._cached_bind_processor(self.dialect))
for bindparam in self.bind_names)
if value is not None
)
def is_subquery(self):
return len(self.stack) > 1
@property
def sql_compiler(self):
return self
def construct_params(self, params=None, _group_number=None, _check=True):
"""return a dictionary of bind parameter keys and values"""
if params:
pd = {}
for bindparam, name in self.bind_names.items():
if bindparam.key in params:
pd[name] = params[bindparam.key]
elif name in params:
pd[name] = params[name]
elif _check and bindparam.required:
if _group_number:
raise exc.InvalidRequestError(
"A value is required for bind parameter %r, "
"in parameter group %d" %
(bindparam.key, _group_number))
else:
raise exc.InvalidRequestError(
"A value is required for bind parameter %r"
% bindparam.key)
else:
pd[name] = bindparam.effective_value
return pd
else:
pd = {}
for bindparam in self.bind_names:
if _check and bindparam.required:
if _group_number:
raise exc.InvalidRequestError(
"A value is required for bind parameter %r, "
"in parameter group %d" %
(bindparam.key, _group_number))
else:
raise exc.InvalidRequestError(
"A value is required for bind parameter %r"
% bindparam.key)
pd[self.bind_names[bindparam]] = bindparam.effective_value
return pd
@property
def params(self):
"""Return the bind param dictionary embedded into this
compiled object, for those values that are present."""
return self.construct_params(_check=False)
def default_from(self):
"""Called when a SELECT statement has no froms, and no FROM clause is
to be appended.
Gives Oracle a chance to tack on a ``FROM DUAL`` to the string output.
"""
return ""
def visit_grouping(self, grouping, asfrom=False, **kwargs):
return "(" + grouping.element._compiler_dispatch(self, **kwargs) + ")"
def visit_label(self, label,
add_to_result_map=None,
within_label_clause=False,
within_columns_clause=False,
render_label_as_label=None,
**kw):
# only render labels within the columns clause
# or ORDER BY clause of a select. dialect-specific compilers
# can modify this behavior.
render_label_with_as = within_columns_clause and not within_label_clause
render_label_only = render_label_as_label is label
if render_label_only or render_label_with_as:
if isinstance(label.name, elements._truncated_label):
labelname = self._truncated_identifier("colident", label.name)
else:
labelname = label.name
if render_label_with_as:
if add_to_result_map is not None:
add_to_result_map(
labelname,
label.name,
(label, labelname, ) + label._alt_names,
label.type
)
return label.element._compiler_dispatch(self,
within_columns_clause=True,
within_label_clause=True,
**kw) + \
OPERATORS[operators.as_] + \
self.preparer.format_label(label, labelname)
elif render_label_only:
return labelname
else:
return label.element._compiler_dispatch(self,
within_columns_clause=False,
**kw)
def visit_column(self, column, add_to_result_map=None,
include_table=True, **kwargs):
name = orig_name = column.name
if name is None:
raise exc.CompileError("Cannot compile Column object until "
"its 'name' is assigned.")
is_literal = column.is_literal
if not is_literal and isinstance(name, elements._truncated_label):
name = self._truncated_identifier("colident", name)
if add_to_result_map is not None:
add_to_result_map(
name,
orig_name,
(column, name, column.key),
column.type
)
if is_literal:
name = self.escape_literal_column(name)
else:
name = self.preparer.quote(name)
table = column.table
if table is None or not include_table or not table.named_with_column:
return name
else:
if table.schema:
schema_prefix = self.preparer.quote_schema(table.schema) + '.'
else:
schema_prefix = ''
tablename = table.name
if isinstance(tablename, elements._truncated_label):
tablename = self._truncated_identifier("alias", tablename)
return schema_prefix + \
self.preparer.quote(tablename) + \
"." + name
def escape_literal_column(self, text):
"""provide escaping for the literal_column() construct."""
# TODO: some dialects might need different behavior here
return text.replace('%', '%%')
def visit_fromclause(self, fromclause, **kwargs):
return fromclause.name
def visit_index(self, index, **kwargs):
return index.name
def visit_typeclause(self, typeclause, **kwargs):
return self.dialect.type_compiler.process(typeclause.type)
def post_process_text(self, text):
return text
def visit_textclause(self, textclause, **kw):
def do_bindparam(m):
name = m.group(1)
if name in textclause._bindparams:
return self.process(textclause._bindparams[name], **kw)
else:
return self.bindparam_string(name, **kw)
# un-escape any \:params
return BIND_PARAMS_ESC.sub(lambda m: m.group(1),
BIND_PARAMS.sub(do_bindparam,
self.post_process_text(textclause.text))
)
def visit_text_as_from(self, taf, iswrapper=False,
compound_index=0, force_result_map=False,
asfrom=False,
parens=True, **kw):
toplevel = not self.stack
entry = self._default_stack_entry if toplevel else self.stack[-1]
populate_result_map = force_result_map or (
compound_index == 0 and (
toplevel or \
entry['iswrapper']
)
)
if populate_result_map:
for c in taf.column_args:
self.process(c, within_columns_clause=True,
add_to_result_map=self._add_to_result_map)
text = self.process(taf.element, **kw)
if asfrom and parens:
text = "(%s)" % text
return text
def visit_null(self, expr, **kw):
return 'NULL'
def visit_true(self, expr, **kw):
if self.dialect.supports_native_boolean:
return 'true'
else:
return "1"
def visit_false(self, expr, **kw):
if self.dialect.supports_native_boolean:
return 'false'
else:
return "0"
def visit_clauselist(self, clauselist, order_by_select=None, **kw):
if order_by_select is not None:
return self._order_by_clauselist(
clauselist, order_by_select, **kw)
sep = clauselist.operator
if sep is None:
sep = " "
else:
sep = OPERATORS[clauselist.operator]
return sep.join(
s for s in
(
c._compiler_dispatch(self, **kw)
for c in clauselist.clauses)
if s)
def _order_by_clauselist(self, clauselist, order_by_select, **kw):
# look through raw columns collection for labels.
# note that its OK we aren't expanding tables and other selectables
# here; we can only add a label in the ORDER BY for an individual
# label expression in the columns clause.
raw_col = set(l._order_by_label_element.name
for l in order_by_select._raw_columns
if l._order_by_label_element is not None)
return ", ".join(
s for s in
(
c._compiler_dispatch(self,
render_label_as_label=
c._order_by_label_element if
c._order_by_label_element is not None and
c._order_by_label_element.name in raw_col
else None,
**kw)
for c in clauselist.clauses)
if s)
def visit_case(self, clause, **kwargs):
x = "CASE "
if clause.value is not None:
x += clause.value._compiler_dispatch(self, **kwargs) + " "
for cond, result in clause.whens:
x += "WHEN " + cond._compiler_dispatch(
self, **kwargs
) + " THEN " + result._compiler_dispatch(
self, **kwargs) + " "
if clause.else_ is not None:
x += "ELSE " + clause.else_._compiler_dispatch(
self, **kwargs
) + " "
x += "END"
return x
def visit_cast(self, cast, **kwargs):
return "CAST(%s AS %s)" % \
(cast.clause._compiler_dispatch(self, **kwargs),
cast.typeclause._compiler_dispatch(self, **kwargs))
def visit_over(self, over, **kwargs):
return "%s OVER (%s)" % (
over.func._compiler_dispatch(self, **kwargs),
' '.join(
'%s BY %s' % (word, clause._compiler_dispatch(self, **kwargs))
for word, clause in (
('PARTITION', over.partition_by),
('ORDER', over.order_by)
)
if clause is not None and len(clause)
)
)
def visit_extract(self, extract, **kwargs):
field = self.extract_map.get(extract.field, extract.field)
return "EXTRACT(%s FROM %s)" % (field,
extract.expr._compiler_dispatch(self, **kwargs))
def visit_function(self, func, add_to_result_map=None, **kwargs):
if add_to_result_map is not None:
add_to_result_map(
func.name, func.name, (), func.type
)
disp = getattr(self, "visit_%s_func" % func.name.lower(), None)
if disp:
return disp(func, **kwargs)
else:
name = FUNCTIONS.get(func.__class__, func.name + "%(expr)s")
return ".".join(list(func.packagenames) + [name]) % \
{'expr': self.function_argspec(func, **kwargs)}
def visit_next_value_func(self, next_value, **kw):
return self.visit_sequence(next_value.sequence)
def visit_sequence(self, sequence):
raise NotImplementedError(
"Dialect '%s' does not support sequence increments." %
self.dialect.name
)
def function_argspec(self, func, **kwargs):
return func.clause_expr._compiler_dispatch(self, **kwargs)
def visit_compound_select(self, cs, asfrom=False,
parens=True, compound_index=0, **kwargs):
toplevel = not self.stack
entry = self._default_stack_entry if toplevel else self.stack[-1]
self.stack.append(
{
'correlate_froms': entry['correlate_froms'],
'iswrapper': toplevel,
'asfrom_froms': entry['asfrom_froms']
})
keyword = self.compound_keywords.get(cs.keyword)
text = (" " + keyword + " ").join(
(c._compiler_dispatch(self,
asfrom=asfrom, parens=False,
compound_index=i, **kwargs)
for i, c in enumerate(cs.selects))
)
group_by = cs._group_by_clause._compiler_dispatch(
self, asfrom=asfrom, **kwargs)
if group_by:
text += " GROUP BY " + group_by
text += self.order_by_clause(cs, **kwargs)
text += (cs._limit is not None or cs._offset is not None) and \
self.limit_clause(cs) or ""
if self.ctes and \
compound_index == 0 and toplevel:
text = self._render_cte_clause() + text
self.stack.pop(-1)
if asfrom and parens:
return "(" + text + ")"
else:
return text
def visit_unary(self, unary, **kw):
if unary.operator:
if unary.modifier:
raise exc.CompileError(
"Unary expression does not support operator "
"and modifier simultaneously")
disp = getattr(self, "visit_%s_unary_operator" %
unary.operator.__name__, None)
if disp:
return disp(unary, unary.operator, **kw)
else:
return self._generate_generic_unary_operator(unary,
OPERATORS[unary.operator], **kw)
elif unary.modifier:
disp = getattr(self, "visit_%s_unary_modifier" %
unary.modifier.__name__, None)
if disp:
return disp(unary, unary.modifier, **kw)
else:
return self._generate_generic_unary_modifier(unary,
OPERATORS[unary.modifier], **kw)
else:
raise exc.CompileError(
"Unary expression has no operator or modifier")
def visit_istrue_unary_operator(self, element, operator, **kw):
if self.dialect.supports_native_boolean:
return self.process(element.element, **kw)
else:
return "%s = 1" % self.process(element.element, **kw)
def visit_isfalse_unary_operator(self, element, operator, **kw):
if self.dialect.supports_native_boolean:
return "NOT %s" % self.process(element.element, **kw)
else:
return "%s = 0" % self.process(element.element, **kw)
def visit_binary(self, binary, **kw):
# don't allow "? = ?" to render
if self.ansi_bind_rules and \
isinstance(binary.left, elements.BindParameter) and \
isinstance(binary.right, elements.BindParameter):
kw['literal_binds'] = True
operator = binary.operator
disp = getattr(self, "visit_%s_binary" % operator.__name__, None)
if disp:
return disp(binary, operator, **kw)
else:
try:
opstring = OPERATORS[operator]
except KeyError:
raise exc.UnsupportedCompilationError(self, operator)
else:
return self._generate_generic_binary(binary, opstring, **kw)
def visit_custom_op_binary(self, element, operator, **kw):
return self._generate_generic_binary(element,
" " + operator.opstring + " ", **kw)
def visit_custom_op_unary_operator(self, element, operator, **kw):
return self._generate_generic_unary_operator(element,
operator.opstring + " ", **kw)
def visit_custom_op_unary_modifier(self, element, operator, **kw):
return self._generate_generic_unary_modifier(element,
" " + operator.opstring, **kw)
def _generate_generic_binary(self, binary, opstring, **kw):
return binary.left._compiler_dispatch(self, **kw) + \
opstring + \
binary.right._compiler_dispatch(self, **kw)
def _generate_generic_unary_operator(self, unary, opstring, **kw):
return opstring + unary.element._compiler_dispatch(self, **kw)
def _generate_generic_unary_modifier(self, unary, opstring, **kw):
return unary.element._compiler_dispatch(self, **kw) + opstring
@util.memoized_property
def _like_percent_literal(self):
return elements.literal_column("'%'", type_=sqltypes.STRINGTYPE)
def visit_contains_op_binary(self, binary, operator, **kw):
binary = binary._clone()
percent = self._like_percent_literal
binary.right = percent.__add__(binary.right).__add__(percent)
return self.visit_like_op_binary(binary, operator, **kw)
def visit_notcontains_op_binary(self, binary, operator, **kw):
binary = binary._clone()
percent = self._like_percent_literal
binary.right = percent.__add__(binary.right).__add__(percent)
return self.visit_notlike_op_binary(binary, operator, **kw)
def visit_startswith_op_binary(self, binary, operator, **kw):
binary = binary._clone()
percent = self._like_percent_literal
binary.right = percent.__radd__(
binary.right
)
return self.visit_like_op_binary(binary, operator, **kw)
def visit_notstartswith_op_binary(self, binary, operator, **kw):
binary = binary._clone()
percent = self._like_percent_literal
binary.right = percent.__radd__(
binary.right
)
return self.visit_notlike_op_binary(binary, operator, **kw)
def visit_endswith_op_binary(self, binary, operator, **kw):
binary = binary._clone()
percent = self._like_percent_literal
binary.right = percent.__add__(binary.right)
return self.visit_like_op_binary(binary, operator, **kw)
def visit_notendswith_op_binary(self, binary, operator, **kw):
binary = binary._clone()
percent = self._like_percent_literal
binary.right = percent.__add__(binary.right)
return self.visit_notlike_op_binary(binary, operator, **kw)
def visit_like_op_binary(self, binary, operator, **kw):
escape = binary.modifiers.get("escape", None)
# TODO: use ternary here, not "and"/ "or"
return '%s LIKE %s' % (
binary.left._compiler_dispatch(self, **kw),
binary.right._compiler_dispatch(self, **kw)) \
+ (
' ESCAPE ' +
self.render_literal_value(escape, sqltypes.STRINGTYPE)
if escape else ''
)
def visit_notlike_op_binary(self, binary, operator, **kw):
escape = binary.modifiers.get("escape", None)
return '%s NOT LIKE %s' % (
binary.left._compiler_dispatch(self, **kw),
binary.right._compiler_dispatch(self, **kw)) \
+ (
' ESCAPE ' +
self.render_literal_value(escape, sqltypes.STRINGTYPE)
if escape else ''
)
def visit_ilike_op_binary(self, binary, operator, **kw):
escape = binary.modifiers.get("escape", None)
return 'lower(%s) LIKE lower(%s)' % (
binary.left._compiler_dispatch(self, **kw),
binary.right._compiler_dispatch(self, **kw)) \
+ (
' ESCAPE ' +
self.render_literal_value(escape, sqltypes.STRINGTYPE)
if escape else ''
)
def visit_notilike_op_binary(self, binary, operator, **kw):
escape = binary.modifiers.get("escape", None)
return 'lower(%s) NOT LIKE lower(%s)' % (
binary.left._compiler_dispatch(self, **kw),
binary.right._compiler_dispatch(self, **kw)) \
+ (
' ESCAPE ' +
self.render_literal_value(escape, sqltypes.STRINGTYPE)
if escape else ''
)
def visit_bindparam(self, bindparam, within_columns_clause=False,
literal_binds=False,
skip_bind_expression=False,
**kwargs):
if not skip_bind_expression and bindparam.type._has_bind_expression:
bind_expression = bindparam.type.bind_expression(bindparam)
return self.process(bind_expression,
skip_bind_expression=True)
if literal_binds or \
(within_columns_clause and \
self.ansi_bind_rules):
if bindparam.value is None and bindparam.callable is None:
raise exc.CompileError("Bind parameter '%s' without a "
"renderable value not allowed here."
% bindparam.key)
return self.render_literal_bindparam(bindparam,
within_columns_clause=True, **kwargs)
name = self._truncate_bindparam(bindparam)
if name in self.binds:
existing = self.binds[name]
if existing is not bindparam:
if (existing.unique or bindparam.unique) and \
not existing.proxy_set.intersection(
bindparam.proxy_set):
raise exc.CompileError(
"Bind parameter '%s' conflicts with "
"unique bind parameter of the same name" %
bindparam.key
)
elif existing._is_crud or bindparam._is_crud:
raise exc.CompileError(
"bindparam() name '%s' is reserved "
"for automatic usage in the VALUES or SET "
"clause of this "
"insert/update statement. Please use a "
"name other than column name when using bindparam() "
"with insert() or update() (for example, 'b_%s')."
% (bindparam.key, bindparam.key)
)
self.binds[bindparam.key] = self.binds[name] = bindparam
return self.bindparam_string(name, **kwargs)
def render_literal_bindparam(self, bindparam, **kw):
value = bindparam.effective_value
return self.render_literal_value(value, bindparam.type)
def render_literal_value(self, value, type_):
"""Render the value of a bind parameter as a quoted literal.
This is used for statement sections that do not accept bind parameters
on the target driver/database.
This should be implemented by subclasses using the quoting services
of the DBAPI.
"""
processor = type_._cached_literal_processor(self.dialect)
if processor:
return processor(value)
else:
raise NotImplementedError(
"Don't know how to literal-quote value %r" % value)
def _truncate_bindparam(self, bindparam):
if bindparam in self.bind_names:
return self.bind_names[bindparam]
bind_name = bindparam.key
if isinstance(bind_name, elements._truncated_label):
bind_name = self._truncated_identifier("bindparam", bind_name)
# add to bind_names for translation
self.bind_names[bindparam] = bind_name
return bind_name
def _truncated_identifier(self, ident_class, name):
if (ident_class, name) in self.truncated_names:
return self.truncated_names[(ident_class, name)]
anonname = name.apply_map(self.anon_map)
if len(anonname) > self.label_length:
counter = self.truncated_names.get(ident_class, 1)
truncname = anonname[0:max(self.label_length - 6, 0)] + \
"_" + hex(counter)[2:]
self.truncated_names[ident_class] = counter + 1
else:
truncname = anonname
self.truncated_names[(ident_class, name)] = truncname
return truncname
def _anonymize(self, name):
return name % self.anon_map
def _process_anon(self, key):
(ident, derived) = key.split(' ', 1)
anonymous_counter = self.anon_map.get(derived, 1)
self.anon_map[derived] = anonymous_counter + 1
return derived + "_" + str(anonymous_counter)
def bindparam_string(self, name, positional_names=None, **kw):
if self.positional:
if positional_names is not None:
positional_names.append(name)
else:
self.positiontup.append(name)
return self.bindtemplate % {'name': name}
def visit_cte(self, cte, asfrom=False, ashint=False,
fromhints=None,
**kwargs):
self._init_cte_state()
if self.positional:
kwargs['positional_names'] = self.cte_positional
if isinstance(cte.name, elements._truncated_label):
cte_name = self._truncated_identifier("alias", cte.name)
else:
cte_name = cte.name
if cte_name in self.ctes_by_name:
existing_cte = self.ctes_by_name[cte_name]
# we've generated a same-named CTE that we are enclosed in,
# or this is the same CTE. just return the name.
if cte in existing_cte._restates or cte is existing_cte:
return self.preparer.format_alias(cte, cte_name)
elif existing_cte in cte._restates:
# we've generated a same-named CTE that is
# enclosed in us - we take precedence, so
# discard the text for the "inner".
del self.ctes[existing_cte]
else:
raise exc.CompileError(
"Multiple, unrelated CTEs found with "
"the same name: %r" %
cte_name)
self.ctes_by_name[cte_name] = cte
if cte._cte_alias is not None:
orig_cte = cte._cte_alias
if orig_cte not in self.ctes:
self.visit_cte(orig_cte)
cte_alias_name = cte._cte_alias.name
if isinstance(cte_alias_name, elements._truncated_label):
cte_alias_name = self._truncated_identifier("alias", cte_alias_name)
else:
orig_cte = cte
cte_alias_name = None
if not cte_alias_name and cte not in self.ctes:
if cte.recursive:
self.ctes_recursive = True
text = self.preparer.format_alias(cte, cte_name)
if cte.recursive:
if isinstance(cte.original, selectable.Select):
col_source = cte.original
elif isinstance(cte.original, selectable.CompoundSelect):
col_source = cte.original.selects[0]
else:
assert False
recur_cols = [c for c in
util.unique_list(col_source.inner_columns)
if c is not None]
text += "(%s)" % (", ".join(
self.preparer.format_column(ident)
for ident in recur_cols))
text += " AS \n" + \
cte.original._compiler_dispatch(
self, asfrom=True, **kwargs
)
self.ctes[cte] = text
if asfrom:
if cte_alias_name:
text = self.preparer.format_alias(cte, cte_alias_name)
text += " AS " + cte_name
else:
return self.preparer.format_alias(cte, cte_name)
return text
def visit_alias(self, alias, asfrom=False, ashint=False,
iscrud=False,
fromhints=None, **kwargs):
if asfrom or ashint:
if isinstance(alias.name, elements._truncated_label):
alias_name = self._truncated_identifier("alias", alias.name)
else:
alias_name = alias.name
if ashint:
return self.preparer.format_alias(alias, alias_name)
elif asfrom:
ret = alias.original._compiler_dispatch(self,
asfrom=True, **kwargs) + \
" AS " + \
self.preparer.format_alias(alias, alias_name)
if fromhints and alias in fromhints:
ret = self.format_from_hint_text(ret, alias,
fromhints[alias], iscrud)
return ret
else:
return alias.original._compiler_dispatch(self, **kwargs)
def _add_to_result_map(self, keyname, name, objects, type_):
if not self.dialect.case_sensitive:
keyname = keyname.lower()
if keyname in self.result_map:
# conflicting keyname, just double up the list
# of objects. this will cause an "ambiguous name"
# error if an attempt is made by the result set to
# access.
e_name, e_obj, e_type = self.result_map[keyname]
self.result_map[keyname] = e_name, e_obj + objects, e_type
else:
self.result_map[keyname] = name, objects, type_
def _label_select_column(self, select, column,
populate_result_map,
asfrom, column_clause_args,
name=None,
within_columns_clause=True):
"""produce labeled columns present in a select()."""
if column.type._has_column_expression and \
populate_result_map:
col_expr = column.type.column_expression(column)
add_to_result_map = lambda keyname, name, objects, type_: \
self._add_to_result_map(
keyname, name,
objects + (column,), type_)
else:
col_expr = column
if populate_result_map:
add_to_result_map = self._add_to_result_map
else:
add_to_result_map = None
if not within_columns_clause:
result_expr = col_expr
elif isinstance(column, elements.Label):
if col_expr is not column:
result_expr = _CompileLabel(
col_expr,
column.name,
alt_names=(column.element,)
)
else:
result_expr = col_expr
elif select is not None and name:
result_expr = _CompileLabel(
col_expr,
name,
alt_names=(column._key_label,)
)
elif \
asfrom and \
isinstance(column, elements.ColumnClause) and \
not column.is_literal and \
column.table is not None and \
not isinstance(column.table, selectable.Select):
result_expr = _CompileLabel(col_expr,
elements._as_truncated(column.name),
alt_names=(column.key,))
elif not isinstance(column,
(elements.UnaryExpression, elements.TextClause)) \
and (not hasattr(column, 'name') or \
isinstance(column, functions.Function)):
result_expr = _CompileLabel(col_expr, column.anon_label)
elif col_expr is not column:
# TODO: are we sure "column" has a .name and .key here ?
# assert isinstance(column, elements.ColumnClause)
result_expr = _CompileLabel(col_expr,
elements._as_truncated(column.name),
alt_names=(column.key,))
else:
result_expr = col_expr
column_clause_args.update(
within_columns_clause=within_columns_clause,
add_to_result_map=add_to_result_map
)
return result_expr._compiler_dispatch(
self,
**column_clause_args
)
def format_from_hint_text(self, sqltext, table, hint, iscrud):
hinttext = self.get_from_hint_text(table, hint)
if hinttext:
sqltext += " " + hinttext
return sqltext
def get_select_hint_text(self, byfroms):
return None
def get_from_hint_text(self, table, text):
return None
def get_crud_hint_text(self, table, text):
return None
def _transform_select_for_nested_joins(self, select):
"""Rewrite any "a JOIN (b JOIN c)" expression as
"a JOIN (select * from b JOIN c) AS anon", to support
databases that can't parse a parenthesized join correctly
(i.e. sqlite the main one).
"""
cloned = {}
column_translate = [{}]
def visit(element, **kw):
if element in column_translate[-1]:
return column_translate[-1][element]
elif element in cloned:
return cloned[element]
newelem = cloned[element] = element._clone()
if newelem.is_selectable and newelem._is_join and \
isinstance(newelem.right, selectable.FromGrouping):
newelem._reset_exported()
newelem.left = visit(newelem.left, **kw)
right = visit(newelem.right, **kw)
selectable_ = selectable.Select(
[right.element],
use_labels=True).alias()
for c in selectable_.c:
c._key_label = c.key
c._label = c.name
translate_dict = dict(
zip(newelem.right.element.c, selectable_.c)
)
# translating from both the old and the new
# because different select() structures will lead us
# to traverse differently
translate_dict[right.element.left] = selectable_
translate_dict[right.element.right] = selectable_
translate_dict[newelem.right.element.left] = selectable_
translate_dict[newelem.right.element.right] = selectable_
# propagate translations that we've gained
# from nested visit(newelem.right) outwards
# to the enclosing select here. this happens
# only when we have more than one level of right
# join nesting, i.e. "a JOIN (b JOIN (c JOIN d))"
for k, v in list(column_translate[-1].items()):
if v in translate_dict:
# remarkably, no current ORM tests (May 2013)
# hit this condition, only test_join_rewriting
# does.
column_translate[-1][k] = translate_dict[v]
column_translate[-1].update(translate_dict)
newelem.right = selectable_
newelem.onclause = visit(newelem.onclause, **kw)
elif newelem.is_selectable and newelem._is_from_container:
# if we hit an Alias or CompoundSelect, put a marker in the
# stack.
kw['transform_clue'] = 'select_container'
newelem._copy_internals(clone=visit, **kw)
elif newelem.is_selectable and newelem._is_select:
barrier_select = kw.get('transform_clue', None) == 'select_container'
# if we're still descended from an Alias/CompoundSelect, we're
# in a FROM clause, so start with a new translate collection
if barrier_select:
column_translate.append({})
kw['transform_clue'] = 'inside_select'
newelem._copy_internals(clone=visit, **kw)
if barrier_select:
del column_translate[-1]
else:
newelem._copy_internals(clone=visit, **kw)
return newelem
return visit(select)
def _transform_result_map_for_nested_joins(self, select, transformed_select):
inner_col = dict((c._key_label, c) for
c in transformed_select.inner_columns)
d = dict(
(inner_col[c._key_label], c)
for c in select.inner_columns
)
for key, (name, objs, typ) in list(self.result_map.items()):
objs = tuple([d.get(col, col) for col in objs])
self.result_map[key] = (name, objs, typ)
_default_stack_entry = util.immutabledict([
('iswrapper', False),
('correlate_froms', frozenset()),
('asfrom_froms', frozenset())
])
def _display_froms_for_select(self, select, asfrom):
# utility method to help external dialects
# get the correct from list for a select.
# specifically the oracle dialect needs this feature
# right now.
toplevel = not self.stack
entry = self._default_stack_entry if toplevel else self.stack[-1]
correlate_froms = entry['correlate_froms']
asfrom_froms = entry['asfrom_froms']
if asfrom:
froms = select._get_display_froms(
explicit_correlate_froms=\
correlate_froms.difference(asfrom_froms),
implicit_correlate_froms=())
else:
froms = select._get_display_froms(
explicit_correlate_froms=correlate_froms,
implicit_correlate_froms=asfrom_froms)
return froms
def visit_select(self, select, asfrom=False, parens=True,
iswrapper=False, fromhints=None,
compound_index=0,
force_result_map=False,
positional_names=None,
nested_join_translation=False,
**kwargs):
needs_nested_translation = \
select.use_labels and \
not nested_join_translation and \
not self.stack and \
not self.dialect.supports_right_nested_joins
if needs_nested_translation:
transformed_select = self._transform_select_for_nested_joins(select)
text = self.visit_select(
transformed_select, asfrom=asfrom, parens=parens,
iswrapper=iswrapper, fromhints=fromhints,
compound_index=compound_index,
force_result_map=force_result_map,
positional_names=positional_names,
nested_join_translation=True, **kwargs
)
toplevel = not self.stack
entry = self._default_stack_entry if toplevel else self.stack[-1]
populate_result_map = force_result_map or (
compound_index == 0 and (
toplevel or \
entry['iswrapper']
)
)
if needs_nested_translation:
if populate_result_map:
self._transform_result_map_for_nested_joins(
select, transformed_select)
return text
correlate_froms = entry['correlate_froms']
asfrom_froms = entry['asfrom_froms']
if asfrom:
froms = select._get_display_froms(
explicit_correlate_froms=
correlate_froms.difference(asfrom_froms),
implicit_correlate_froms=())
else:
froms = select._get_display_froms(
explicit_correlate_froms=correlate_froms,
implicit_correlate_froms=asfrom_froms)
new_correlate_froms = set(selectable._from_objects(*froms))
all_correlate_froms = new_correlate_froms.union(correlate_froms)
new_entry = {
'asfrom_froms': new_correlate_froms,
'iswrapper': iswrapper,
'correlate_froms': all_correlate_froms
}
self.stack.append(new_entry)
column_clause_args = kwargs.copy()
column_clause_args.update({
'positional_names': positional_names,
'within_label_clause': False,
'within_columns_clause': False
})
# the actual list of columns to print in the SELECT column list.
inner_columns = [
c for c in [
self._label_select_column(select,
column,
populate_result_map, asfrom,
column_clause_args,
name=name)
for name, column in select._columns_plus_names
]
if c is not None
]
text = "SELECT " # we're off to a good start !
if select._hints:
byfrom = dict([
(from_, hinttext % {
'name':from_._compiler_dispatch(
self, ashint=True)
})
for (from_, dialect), hinttext in
select._hints.items()
if dialect in ('*', self.dialect.name)
])
hint_text = self.get_select_hint_text(byfrom)
if hint_text:
text += hint_text + " "
if select._prefixes:
text += self._generate_prefixes(select, select._prefixes, **kwargs)
text += self.get_select_precolumns(select)
text += ', '.join(inner_columns)
if froms:
text += " \nFROM "
if select._hints:
text += ', '.join([f._compiler_dispatch(self,
asfrom=True, fromhints=byfrom,
**kwargs)
for f in froms])
else:
text += ', '.join([f._compiler_dispatch(self,
asfrom=True, **kwargs)
for f in froms])
else:
text += self.default_from()
if select._whereclause is not None:
t = select._whereclause._compiler_dispatch(self, **kwargs)
if t:
text += " \nWHERE " + t
if select._group_by_clause.clauses:
group_by = select._group_by_clause._compiler_dispatch(
self, **kwargs)
if group_by:
text += " GROUP BY " + group_by
if select._having is not None:
t = select._having._compiler_dispatch(self, **kwargs)
if t:
text += " \nHAVING " + t
if select._order_by_clause.clauses:
if self.dialect.supports_simple_order_by_label:
order_by_select = select
else:
order_by_select = None
text += self.order_by_clause(select,
order_by_select=order_by_select, **kwargs)
if select._limit is not None or select._offset is not None:
text += self.limit_clause(select)
if select._for_update_arg is not None:
text += self.for_update_clause(select)
if self.ctes and \
compound_index == 0 and toplevel:
text = self._render_cte_clause() + text
self.stack.pop(-1)
if asfrom and parens:
return "(" + text + ")"
else:
return text
def _generate_prefixes(self, stmt, prefixes, **kw):
clause = " ".join(
prefix._compiler_dispatch(self, **kw)
for prefix, dialect_name in prefixes
if dialect_name is None or
dialect_name == self.dialect.name
)
if clause:
clause += " "
return clause
def _render_cte_clause(self):
if self.positional:
self.positiontup = self.cte_positional + self.positiontup
cte_text = self.get_cte_preamble(self.ctes_recursive) + " "
cte_text += ", \n".join(
[txt for txt in self.ctes.values()]
)
cte_text += "\n "
return cte_text
def get_cte_preamble(self, recursive):
if recursive:
return "WITH RECURSIVE"
else:
return "WITH"
def get_select_precolumns(self, select):
"""Called when building a ``SELECT`` statement, position is just
before column list.
"""
return select._distinct and "DISTINCT " or ""
def order_by_clause(self, select, **kw):
order_by = select._order_by_clause._compiler_dispatch(self, **kw)
if order_by:
return " ORDER BY " + order_by
else:
return ""
def for_update_clause(self, select):
return " FOR UPDATE"
def returning_clause(self, stmt, returning_cols):
raise exc.CompileError(
"RETURNING is not supported by this "
"dialect's statement compiler.")
def limit_clause(self, select):
text = ""
if select._limit is not None:
text += "\n LIMIT " + self.process(elements.literal(select._limit))
if select._offset is not None:
if select._limit is None:
text += "\n LIMIT -1"
text += " OFFSET " + self.process(elements.literal(select._offset))
return text
def visit_table(self, table, asfrom=False, iscrud=False, ashint=False,
fromhints=None, **kwargs):
if asfrom or ashint:
if getattr(table, "schema", None):
ret = self.preparer.quote_schema(table.schema) + \
"." + self.preparer.quote(table.name)
else:
ret = self.preparer.quote(table.name)
if fromhints and table in fromhints:
ret = self.format_from_hint_text(ret, table,
fromhints[table], iscrud)
return ret
else:
return ""
def visit_join(self, join, asfrom=False, **kwargs):
return (
join.left._compiler_dispatch(self, asfrom=True, **kwargs) +
(join.isouter and " LEFT OUTER JOIN " or " JOIN ") +
join.right._compiler_dispatch(self, asfrom=True, **kwargs) +
" ON " +
join.onclause._compiler_dispatch(self, **kwargs)
)
def visit_insert(self, insert_stmt, **kw):
self.isinsert = True
colparams = self._get_colparams(insert_stmt, **kw)
if not colparams and \
not self.dialect.supports_default_values and \
not self.dialect.supports_empty_insert:
raise exc.CompileError("The '%s' dialect with current database "
"version settings does not support empty "
"inserts." %
self.dialect.name)
if insert_stmt._has_multi_parameters:
if not self.dialect.supports_multivalues_insert:
raise exc.CompileError("The '%s' dialect with current database "
"version settings does not support "
"in-place multirow inserts." %
self.dialect.name)
colparams_single = colparams[0]
else:
colparams_single = colparams
preparer = self.preparer
supports_default_values = self.dialect.supports_default_values
text = "INSERT "
if insert_stmt._prefixes:
text += self._generate_prefixes(insert_stmt,
insert_stmt._prefixes, **kw)
text += "INTO "
table_text = preparer.format_table(insert_stmt.table)
if insert_stmt._hints:
dialect_hints = dict([
(table, hint_text)
for (table, dialect), hint_text in
insert_stmt._hints.items()
if dialect in ('*', self.dialect.name)
])
if insert_stmt.table in dialect_hints:
table_text = self.format_from_hint_text(
table_text,
insert_stmt.table,
dialect_hints[insert_stmt.table],
True
)
text += table_text
if colparams_single or not supports_default_values:
text += " (%s)" % ', '.join([preparer.format_column(c[0])
for c in colparams_single])
if self.returning or insert_stmt._returning:
self.returning = self.returning or insert_stmt._returning
returning_clause = self.returning_clause(
insert_stmt, self.returning)
if self.returning_precedes_values:
text += " " + returning_clause
if insert_stmt.select is not None:
text += " %s" % self.process(insert_stmt.select, **kw)
elif not colparams and supports_default_values:
text += " DEFAULT VALUES"
elif insert_stmt._has_multi_parameters:
text += " VALUES %s" % (
", ".join(
"(%s)" % (
', '.join(c[1] for c in colparam_set)
)
for colparam_set in colparams
)
)
else:
text += " VALUES (%s)" % \
', '.join([c[1] for c in colparams])
if self.returning and not self.returning_precedes_values:
text += " " + returning_clause
return text
def update_limit_clause(self, update_stmt):
"""Provide a hook for MySQL to add LIMIT to the UPDATE"""
return None
def update_tables_clause(self, update_stmt, from_table,
extra_froms, **kw):
"""Provide a hook to override the initial table clause
in an UPDATE statement.
MySQL overrides this.
"""
return from_table._compiler_dispatch(self, asfrom=True,
iscrud=True, **kw)
def update_from_clause(self, update_stmt,
from_table, extra_froms,
from_hints,
**kw):
"""Provide a hook to override the generation of an
UPDATE..FROM clause.
MySQL and MSSQL override this.
"""
return "FROM " + ', '.join(
t._compiler_dispatch(self, asfrom=True,
fromhints=from_hints, **kw)
for t in extra_froms)
def visit_update(self, update_stmt, **kw):
self.stack.append(
{'correlate_froms': set([update_stmt.table]),
"iswrapper": False,
"asfrom_froms": set([update_stmt.table])})
self.isupdate = True
extra_froms = update_stmt._extra_froms
text = "UPDATE "
if update_stmt._prefixes:
text += self._generate_prefixes(update_stmt,
update_stmt._prefixes, **kw)
table_text = self.update_tables_clause(update_stmt, update_stmt.table,
extra_froms, **kw)
colparams = self._get_colparams(update_stmt, **kw)
if update_stmt._hints:
dialect_hints = dict([
(table, hint_text)
for (table, dialect), hint_text in
update_stmt._hints.items()
if dialect in ('*', self.dialect.name)
])
if update_stmt.table in dialect_hints:
table_text = self.format_from_hint_text(
table_text,
update_stmt.table,
dialect_hints[update_stmt.table],
True
)
else:
dialect_hints = None
text += table_text
text += ' SET '
include_table = extra_froms and \
self.render_table_with_column_in_update_from
text += ', '.join(
c[0]._compiler_dispatch(self,
include_table=include_table) +
'=' + c[1] for c in colparams
)
if self.returning or update_stmt._returning:
if not self.returning:
self.returning = update_stmt._returning
if self.returning_precedes_values:
text += " " + self.returning_clause(
update_stmt, self.returning)
if extra_froms:
extra_from_text = self.update_from_clause(
update_stmt,
update_stmt.table,
extra_froms,
dialect_hints, **kw)
if extra_from_text:
text += " " + extra_from_text
if update_stmt._whereclause is not None:
text += " WHERE " + self.process(update_stmt._whereclause)
limit_clause = self.update_limit_clause(update_stmt)
if limit_clause:
text += " " + limit_clause
if self.returning and not self.returning_precedes_values:
text += " " + self.returning_clause(
update_stmt, self.returning)
self.stack.pop(-1)
return text
def _create_crud_bind_param(self, col, value, required=False, name=None):
if name is None:
name = col.key
bindparam = elements.BindParameter(name, value,
type_=col.type, required=required)
bindparam._is_crud = True
return bindparam._compiler_dispatch(self)
@util.memoized_property
def _key_getters_for_crud_column(self):
if self.isupdate and self.statement._extra_froms:
# when extra tables are present, refer to the columns
# in those extra tables as table-qualified, including in
# dictionaries and when rendering bind param names.
# the "main" table of the statement remains unqualified,
# allowing the most compatibility with a non-multi-table
# statement.
_et = set(self.statement._extra_froms)
def _column_as_key(key):
str_key = elements._column_as_key(key)
if hasattr(key, 'table') and key.table in _et:
return (key.table.name, str_key)
else:
return str_key
def _getattr_col_key(col):
if col.table in _et:
return (col.table.name, col.key)
else:
return col.key
def _col_bind_name(col):
if col.table in _et:
return "%s_%s" % (col.table.name, col.key)
else:
return col.key
else:
_column_as_key = elements._column_as_key
_getattr_col_key = _col_bind_name = operator.attrgetter("key")
return _column_as_key, _getattr_col_key, _col_bind_name
def _get_colparams(self, stmt, **kw):
"""create a set of tuples representing column/string pairs for use
in an INSERT or UPDATE statement.
Also generates the Compiled object's postfetch, prefetch, and
returning column collections, used for default handling and ultimately
populating the ResultProxy's prefetch_cols() and postfetch_cols()
collections.
"""
self.postfetch = []
self.prefetch = []
self.returning = []
# no parameters in the statement, no parameters in the
# compiled params - return binds for all columns
if self.column_keys is None and stmt.parameters is None:
return [
(c, self._create_crud_bind_param(c,
None, required=True))
for c in stmt.table.columns
]
if stmt._has_multi_parameters:
stmt_parameters = stmt.parameters[0]
else:
stmt_parameters = stmt.parameters
# getters - these are normally just column.key,
# but in the case of mysql multi-table update, the rules for
# .key must conditionally take tablename into account
_column_as_key, _getattr_col_key, _col_bind_name = \
self._key_getters_for_crud_column
# if we have statement parameters - set defaults in the
# compiled params
if self.column_keys is None:
parameters = {}
else:
parameters = dict((_column_as_key(key), REQUIRED)
for key in self.column_keys
if not stmt_parameters or
key not in stmt_parameters)
# create a list of column assignment clauses as tuples
values = []
if stmt_parameters is not None:
for k, v in stmt_parameters.items():
colkey = _column_as_key(k)
if colkey is not None:
parameters.setdefault(colkey, v)
else:
# a non-Column expression on the left side;
# add it to values() in an "as-is" state,
# coercing right side to bound param
if elements._is_literal(v):
v = self.process(
elements.BindParameter(None, v, type_=k.type),
**kw)
else:
v = self.process(v.self_group(), **kw)
values.append((k, v))
need_pks = self.isinsert and \
not self.inline and \
not stmt._returning
implicit_returning = need_pks and \
self.dialect.implicit_returning and \
stmt.table.implicit_returning
if self.isinsert:
implicit_return_defaults = implicit_returning and stmt._return_defaults
elif self.isupdate:
implicit_return_defaults = self.dialect.implicit_returning and \
stmt.table.implicit_returning and \
stmt._return_defaults
if implicit_return_defaults:
if stmt._return_defaults is True:
implicit_return_defaults = set(stmt.table.c)
else:
implicit_return_defaults = set(stmt._return_defaults)
postfetch_lastrowid = need_pks and self.dialect.postfetch_lastrowid
check_columns = {}
# special logic that only occurs for multi-table UPDATE
# statements
if self.isupdate and stmt._extra_froms and stmt_parameters:
normalized_params = dict(
(elements._clause_element_as_expr(c), param)
for c, param in stmt_parameters.items()
)
affected_tables = set()
for t in stmt._extra_froms:
for c in t.c:
if c in normalized_params:
affected_tables.add(t)
check_columns[_getattr_col_key(c)] = c
value = normalized_params[c]
if elements._is_literal(value):
value = self._create_crud_bind_param(
c, value, required=value is REQUIRED,
name=_col_bind_name(c))
else:
self.postfetch.append(c)
value = self.process(value.self_group(), **kw)
values.append((c, value))
# determine tables which are actually
# to be updated - process onupdate and
# server_onupdate for these
for t in affected_tables:
for c in t.c:
if c in normalized_params:
continue
elif c.onupdate is not None and not c.onupdate.is_sequence:
if c.onupdate.is_clause_element:
values.append(
(c, self.process(
c.onupdate.arg.self_group(),
**kw)
)
)
self.postfetch.append(c)
else:
values.append(
(c, self._create_crud_bind_param(
c, None, name=_col_bind_name(c)
)
)
)
self.prefetch.append(c)
elif c.server_onupdate is not None:
self.postfetch.append(c)
if self.isinsert and stmt.select_names:
# for an insert from select, we can only use names that
# are given, so only select for those names.
cols = (stmt.table.c[_column_as_key(name)]
for name in stmt.select_names)
else:
# iterate through all table columns to maintain
# ordering, even for those cols that aren't included
cols = stmt.table.columns
for c in cols:
col_key = _getattr_col_key(c)
if col_key in parameters and col_key not in check_columns:
value = parameters.pop(col_key)
if elements._is_literal(value):
value = self._create_crud_bind_param(
c, value, required=value is REQUIRED,
name=_col_bind_name(c)
if not stmt._has_multi_parameters
else "%s_0" % _col_bind_name(c)
)
else:
if isinstance(value, elements.BindParameter) and \
value.type._isnull:
value = value._clone()
value.type = c.type
if c.primary_key and implicit_returning:
self.returning.append(c)
value = self.process(value.self_group(), **kw)
elif implicit_return_defaults and \
c in implicit_return_defaults:
self.returning.append(c)
value = self.process(value.self_group(), **kw)
else:
self.postfetch.append(c)
value = self.process(value.self_group(), **kw)
values.append((c, value))
elif self.isinsert:
if c.primary_key and \
need_pks and \
(
implicit_returning or
not postfetch_lastrowid or
c is not stmt.table._autoincrement_column
):
if implicit_returning:
if c.default is not None:
if c.default.is_sequence:
if self.dialect.supports_sequences and \
(not c.default.optional or \
not self.dialect.sequences_optional):
proc = self.process(c.default, **kw)
values.append((c, proc))
self.returning.append(c)
elif c.default.is_clause_element:
values.append(
(c,
self.process(c.default.arg.self_group(), **kw))
)
self.returning.append(c)
else:
values.append(
(c, self._create_crud_bind_param(c, None))
)
self.prefetch.append(c)
else:
self.returning.append(c)
else:
if (
c.default is not None and
(
not c.default.is_sequence or
self.dialect.supports_sequences
)
) or \
c is stmt.table._autoincrement_column and (
self.dialect.supports_sequences or
self.dialect.preexecute_autoincrement_sequences
):
values.append(
(c, self._create_crud_bind_param(c, None))
)
self.prefetch.append(c)
elif c.default is not None:
if c.default.is_sequence:
if self.dialect.supports_sequences and \
(not c.default.optional or \
not self.dialect.sequences_optional):
proc = self.process(c.default, **kw)
values.append((c, proc))
if implicit_return_defaults and \
c in implicit_return_defaults:
self.returning.append(c)
elif not c.primary_key:
self.postfetch.append(c)
elif c.default.is_clause_element:
values.append(
(c, self.process(c.default.arg.self_group(), **kw))
)
if implicit_return_defaults and \
c in implicit_return_defaults:
self.returning.append(c)
elif not c.primary_key:
# dont add primary key column to postfetch
self.postfetch.append(c)
else:
values.append(
(c, self._create_crud_bind_param(c, None))
)
self.prefetch.append(c)
elif c.server_default is not None:
if implicit_return_defaults and \
c in implicit_return_defaults:
self.returning.append(c)
elif not c.primary_key:
self.postfetch.append(c)
elif implicit_return_defaults and \
c in implicit_return_defaults:
self.returning.append(c)
elif self.isupdate:
if c.onupdate is not None and not c.onupdate.is_sequence:
if c.onupdate.is_clause_element:
values.append(
(c, self.process(c.onupdate.arg.self_group(), **kw))
)
if implicit_return_defaults and \
c in implicit_return_defaults:
self.returning.append(c)
else:
self.postfetch.append(c)
else:
values.append(
(c, self._create_crud_bind_param(c, None))
)
self.prefetch.append(c)
elif c.server_onupdate is not None:
if implicit_return_defaults and \
c in implicit_return_defaults:
self.returning.append(c)
else:
self.postfetch.append(c)
elif implicit_return_defaults and \
c in implicit_return_defaults:
self.returning.append(c)
if parameters and stmt_parameters:
check = set(parameters).intersection(
_column_as_key(k) for k in stmt.parameters
).difference(check_columns)
if check:
raise exc.CompileError(
"Unconsumed column names: %s" %
(", ".join("%s" % c for c in check))
)
if stmt._has_multi_parameters:
values_0 = values
values = [values]
values.extend(
[
(
c,
self._create_crud_bind_param(
c, row[c.key],
name="%s_%d" % (c.key, i + 1)
)
if c.key in row else param
)
for (c, param) in values_0
]
for i, row in enumerate(stmt.parameters[1:])
)
return values
def visit_delete(self, delete_stmt, **kw):
self.stack.append({'correlate_froms': set([delete_stmt.table]),
"iswrapper": False,
"asfrom_froms": set([delete_stmt.table])})
self.isdelete = True
text = "DELETE "
if delete_stmt._prefixes:
text += self._generate_prefixes(delete_stmt,
delete_stmt._prefixes, **kw)
text += "FROM "
table_text = delete_stmt.table._compiler_dispatch(self,
asfrom=True, iscrud=True)
if delete_stmt._hints:
dialect_hints = dict([
(table, hint_text)
for (table, dialect), hint_text in
delete_stmt._hints.items()
if dialect in ('*', self.dialect.name)
])
if delete_stmt.table in dialect_hints:
table_text = self.format_from_hint_text(
table_text,
delete_stmt.table,
dialect_hints[delete_stmt.table],
True
)
else:
dialect_hints = None
text += table_text
if delete_stmt._returning:
self.returning = delete_stmt._returning
if self.returning_precedes_values:
text += " " + self.returning_clause(
delete_stmt, delete_stmt._returning)
if delete_stmt._whereclause is not None:
text += " WHERE "
text += delete_stmt._whereclause._compiler_dispatch(self)
if self.returning and not self.returning_precedes_values:
text += " " + self.returning_clause(
delete_stmt, delete_stmt._returning)
self.stack.pop(-1)
return text
def visit_savepoint(self, savepoint_stmt):
return "SAVEPOINT %s" % self.preparer.format_savepoint(savepoint_stmt)
def visit_rollback_to_savepoint(self, savepoint_stmt):
return "ROLLBACK TO SAVEPOINT %s" % \
self.preparer.format_savepoint(savepoint_stmt)
def visit_release_savepoint(self, savepoint_stmt):
return "RELEASE SAVEPOINT %s" % \
self.preparer.format_savepoint(savepoint_stmt)
class DDLCompiler(Compiled):
@util.memoized_property
def sql_compiler(self):
return self.dialect.statement_compiler(self.dialect, None)
@util.memoized_property
def type_compiler(self):
return self.dialect.type_compiler
@property
def preparer(self):
return self.dialect.identifier_preparer
def construct_params(self, params=None):
return None
def visit_ddl(self, ddl, **kwargs):
# table events can substitute table and schema name
context = ddl.context
if isinstance(ddl.target, schema.Table):
context = context.copy()
preparer = self.dialect.identifier_preparer
path = preparer.format_table_seq(ddl.target)
if len(path) == 1:
table, sch = path[0], ''
else:
table, sch = path[-1], path[0]
context.setdefault('table', table)
context.setdefault('schema', sch)
context.setdefault('fullname', preparer.format_table(ddl.target))
return self.sql_compiler.post_process_text(ddl.statement % context)
def visit_create_schema(self, create):
schema = self.preparer.format_schema(create.element)
return "CREATE SCHEMA " + schema
def visit_drop_schema(self, drop):
schema = self.preparer.format_schema(drop.element)
text = "DROP SCHEMA " + schema
if drop.cascade:
text += " CASCADE"
return text
def visit_create_table(self, create):
table = create.element
preparer = self.dialect.identifier_preparer
text = "\n" + " ".join(['CREATE'] + \
table._prefixes + \
['TABLE',
preparer.format_table(table),
"("])
separator = "\n"
# if only one primary key, specify it along with the column
first_pk = False
for create_column in create.columns:
column = create_column.element
try:
processed = self.process(create_column,
first_pk=column.primary_key
and not first_pk)
if processed is not None:
text += separator
separator = ", \n"
text += "\t" + processed
if column.primary_key:
first_pk = True
except exc.CompileError as ce:
util.raise_from_cause(
exc.CompileError(util.u("(in table '%s', column '%s'): %s") % (
table.description,
column.name,
ce.args[0]
)))
const = self.create_table_constraints(table)
if const:
text += ", \n\t" + const
text += "\n)%s\n\n" % self.post_create_table(table)
return text
def visit_create_column(self, create, first_pk=False):
column = create.element
if column.system:
return None
text = self.get_column_specification(
column,
first_pk=first_pk
)
const = " ".join(self.process(constraint) \
for constraint in column.constraints)
if const:
text += " " + const
return text
def create_table_constraints(self, table):
# On some DB order is significant: visit PK first, then the
# other constraints (engine.ReflectionTest.testbasic failed on FB2)
constraints = []
if table.primary_key:
constraints.append(table.primary_key)
constraints.extend([c for c in table._sorted_constraints
if c is not table.primary_key])
return ", \n\t".join(p for p in
(self.process(constraint)
for constraint in constraints
if (
constraint._create_rule is None or
constraint._create_rule(self))
and (
not self.dialect.supports_alter or
not getattr(constraint, 'use_alter', False)
)) if p is not None
)
def visit_drop_table(self, drop):
return "\nDROP TABLE " + self.preparer.format_table(drop.element)
def visit_drop_view(self, drop):
return "\nDROP VIEW " + self.preparer.format_table(drop.element)
def _verify_index_table(self, index):
if index.table is None:
raise exc.CompileError("Index '%s' is not associated "
"with any table." % index.name)
def visit_create_index(self, create, include_schema=False,
include_table_schema=True):
index = create.element
self._verify_index_table(index)
preparer = self.preparer
text = "CREATE "
if index.unique:
text += "UNIQUE "
text += "INDEX %s ON %s (%s)" \
% (
self._prepared_index_name(index,
include_schema=include_schema),
preparer.format_table(index.table,
use_schema=include_table_schema),
', '.join(
self.sql_compiler.process(expr,
include_table=False, literal_binds=True) for
expr in index.expressions)
)
return text
def visit_drop_index(self, drop):
index = drop.element
return "\nDROP INDEX " + self._prepared_index_name(index,
include_schema=True)
def _prepared_index_name(self, index, include_schema=False):
if include_schema and index.table is not None and index.table.schema:
schema = index.table.schema
schema_name = self.preparer.quote_schema(schema)
else:
schema_name = None
ident = index.name
if isinstance(ident, elements._truncated_label):
max_ = self.dialect.max_index_name_length or \
self.dialect.max_identifier_length
if len(ident) > max_:
ident = ident[0:max_ - 8] + \
"_" + util.md5_hex(ident)[-4:]
else:
self.dialect.validate_identifier(ident)
index_name = self.preparer.quote(ident)
if schema_name:
index_name = schema_name + "." + index_name
return index_name
def visit_add_constraint(self, create):
return "ALTER TABLE %s ADD %s" % (
self.preparer.format_table(create.element.table),
self.process(create.element)
)
def visit_create_sequence(self, create):
text = "CREATE SEQUENCE %s" % \
self.preparer.format_sequence(create.element)
if create.element.increment is not None:
text += " INCREMENT BY %d" % create.element.increment
if create.element.start is not None:
text += " START WITH %d" % create.element.start
return text
def visit_drop_sequence(self, drop):
return "DROP SEQUENCE %s" % \
self.preparer.format_sequence(drop.element)
def visit_drop_constraint(self, drop):
return "ALTER TABLE %s DROP CONSTRAINT %s%s" % (
self.preparer.format_table(drop.element.table),
self.preparer.format_constraint(drop.element),
drop.cascade and " CASCADE" or ""
)
def get_column_specification(self, column, **kwargs):
colspec = self.preparer.format_column(column) + " " + \
self.dialect.type_compiler.process(column.type)
default = self.get_column_default_string(column)
if default is not None:
colspec += " DEFAULT " + default
if not column.nullable:
colspec += " NOT NULL"
return colspec
def post_create_table(self, table):
return ''
def get_column_default_string(self, column):
if isinstance(column.server_default, schema.DefaultClause):
if isinstance(column.server_default.arg, util.string_types):
return "'%s'" % column.server_default.arg
else:
return self.sql_compiler.process(column.server_default.arg)
else:
return None
def visit_check_constraint(self, constraint):
text = ""
if constraint.name is not None:
text += "CONSTRAINT %s " % \
self.preparer.format_constraint(constraint)
text += "CHECK (%s)" % self.sql_compiler.process(constraint.sqltext,
include_table=False,
literal_binds=True)
text += self.define_constraint_deferrability(constraint)
return text
def visit_column_check_constraint(self, constraint):
text = ""
if constraint.name is not None:
text += "CONSTRAINT %s " % \
self.preparer.format_constraint(constraint)
text += "CHECK (%s)" % constraint.sqltext
text += self.define_constraint_deferrability(constraint)
return text
def visit_primary_key_constraint(self, constraint):
if len(constraint) == 0:
return ''
text = ""
if constraint.name is not None:
text += "CONSTRAINT %s " % \
self.preparer.format_constraint(constraint)
text += "PRIMARY KEY "
text += "(%s)" % ', '.join(self.preparer.quote(c.name)
for c in constraint)
text += self.define_constraint_deferrability(constraint)
return text
def visit_foreign_key_constraint(self, constraint):
preparer = self.dialect.identifier_preparer
text = ""
if constraint.name is not None:
text += "CONSTRAINT %s " % \
preparer.format_constraint(constraint)
remote_table = list(constraint._elements.values())[0].column.table
text += "FOREIGN KEY(%s) REFERENCES %s (%s)" % (
', '.join(preparer.quote(f.parent.name)
for f in constraint._elements.values()),
self.define_constraint_remote_table(
constraint, remote_table, preparer),
', '.join(preparer.quote(f.column.name)
for f in constraint._elements.values())
)
text += self.define_constraint_match(constraint)
text += self.define_constraint_cascades(constraint)
text += self.define_constraint_deferrability(constraint)
return text
def define_constraint_remote_table(self, constraint, table, preparer):
"""Format the remote table clause of a CREATE CONSTRAINT clause."""
return preparer.format_table(table)
def visit_unique_constraint(self, constraint):
if len(constraint) == 0:
return ''
text = ""
if constraint.name is not None:
text += "CONSTRAINT %s " % \
self.preparer.format_constraint(constraint)
text += "UNIQUE (%s)" % (
', '.join(self.preparer.quote(c.name)
for c in constraint))
text += self.define_constraint_deferrability(constraint)
return text
def define_constraint_cascades(self, constraint):
text = ""
if constraint.ondelete is not None:
text += " ON DELETE %s" % constraint.ondelete
if constraint.onupdate is not None:
text += " ON UPDATE %s" % constraint.onupdate
return text
def define_constraint_deferrability(self, constraint):
text = ""
if constraint.deferrable is not None:
if constraint.deferrable:
text += " DEFERRABLE"
else:
text += " NOT DEFERRABLE"
if constraint.initially is not None:
text += " INITIALLY %s" % constraint.initially
return text
def define_constraint_match(self, constraint):
text = ""
if constraint.match is not None:
text += " MATCH %s" % constraint.match
return text
class GenericTypeCompiler(TypeCompiler):
def visit_FLOAT(self, type_):
return "FLOAT"
def visit_REAL(self, type_):
return "REAL"
def visit_NUMERIC(self, type_):
if type_.precision is None:
return "NUMERIC"
elif type_.scale is None:
return "NUMERIC(%(precision)s)" % \
{'precision': type_.precision}
else:
return "NUMERIC(%(precision)s, %(scale)s)" % \
{'precision': type_.precision,
'scale': type_.scale}
def visit_DECIMAL(self, type_):
if type_.precision is None:
return "DECIMAL"
elif type_.scale is None:
return "DECIMAL(%(precision)s)" % \
{'precision': type_.precision}
else:
return "DECIMAL(%(precision)s, %(scale)s)" % \
{'precision': type_.precision,
'scale': type_.scale}
def visit_INTEGER(self, type_):
return "INTEGER"
def visit_SMALLINT(self, type_):
return "SMALLINT"
def visit_BIGINT(self, type_):
return "BIGINT"
def visit_TIMESTAMP(self, type_):
return 'TIMESTAMP'
def visit_DATETIME(self, type_):
return "DATETIME"
def visit_DATE(self, type_):
return "DATE"
def visit_TIME(self, type_):
return "TIME"
def visit_CLOB(self, type_):
return "CLOB"
def visit_NCLOB(self, type_):
return "NCLOB"
def _render_string_type(self, type_, name):
text = name
if type_.length:
text += "(%d)" % type_.length
if type_.collation:
text += ' COLLATE "%s"' % type_.collation
return text
def visit_CHAR(self, type_):
return self._render_string_type(type_, "CHAR")
def visit_NCHAR(self, type_):
return self._render_string_type(type_, "NCHAR")
def visit_VARCHAR(self, type_):
return self._render_string_type(type_, "VARCHAR")
def visit_NVARCHAR(self, type_):
return self._render_string_type(type_, "NVARCHAR")
def visit_TEXT(self, type_):
return self._render_string_type(type_, "TEXT")
def visit_BLOB(self, type_):
return "BLOB"
def visit_BINARY(self, type_):
return "BINARY" + (type_.length and "(%d)" % type_.length or "")
def visit_VARBINARY(self, type_):
return "VARBINARY" + (type_.length and "(%d)" % type_.length or "")
def visit_BOOLEAN(self, type_):
return "BOOLEAN"
def visit_large_binary(self, type_):
return self.visit_BLOB(type_)
def visit_boolean(self, type_):
return self.visit_BOOLEAN(type_)
def visit_time(self, type_):
return self.visit_TIME(type_)
def visit_datetime(self, type_):
return self.visit_DATETIME(type_)
def visit_date(self, type_):
return self.visit_DATE(type_)
def visit_big_integer(self, type_):
return self.visit_BIGINT(type_)
def visit_small_integer(self, type_):
return self.visit_SMALLINT(type_)
def visit_integer(self, type_):
return self.visit_INTEGER(type_)
def visit_real(self, type_):
return self.visit_REAL(type_)
def visit_float(self, type_):
return self.visit_FLOAT(type_)
def visit_numeric(self, type_):
return self.visit_NUMERIC(type_)
def visit_string(self, type_):
return self.visit_VARCHAR(type_)
def visit_unicode(self, type_):
return self.visit_VARCHAR(type_)
def visit_text(self, type_):
return self.visit_TEXT(type_)
def visit_unicode_text(self, type_):
return self.visit_TEXT(type_)
def visit_enum(self, type_):
return self.visit_VARCHAR(type_)
def visit_null(self, type_):
raise exc.CompileError("Can't generate DDL for %r; "
"did you forget to specify a "
"type on this Column?" % type_)
def visit_type_decorator(self, type_):
return self.process(type_.type_engine(self.dialect))
def visit_user_defined(self, type_):
return type_.get_col_spec()
class IdentifierPreparer(object):
"""Handle quoting and case-folding of identifiers based on options."""
reserved_words = RESERVED_WORDS
legal_characters = LEGAL_CHARACTERS
illegal_initial_characters = ILLEGAL_INITIAL_CHARACTERS
def __init__(self, dialect, initial_quote='"',
final_quote=None, escape_quote='"', omit_schema=False):
"""Construct a new ``IdentifierPreparer`` object.
initial_quote
Character that begins a delimited identifier.
final_quote
Character that ends a delimited identifier. Defaults to
`initial_quote`.
omit_schema
Prevent prepending schema name. Useful for databases that do
not support schemae.
"""
self.dialect = dialect
self.initial_quote = initial_quote
self.final_quote = final_quote or self.initial_quote
self.escape_quote = escape_quote
self.escape_to_quote = self.escape_quote * 2
self.omit_schema = omit_schema
self._strings = {}
def _escape_identifier(self, value):
"""Escape an identifier.
Subclasses should override this to provide database-dependent
escaping behavior.
"""
return value.replace(self.escape_quote, self.escape_to_quote)
def _unescape_identifier(self, value):
"""Canonicalize an escaped identifier.
Subclasses should override this to provide database-dependent
unescaping behavior that reverses _escape_identifier.
"""
return value.replace(self.escape_to_quote, self.escape_quote)
def quote_identifier(self, value):
"""Quote an identifier.
Subclasses should override this to provide database-dependent
quoting behavior.
"""
return self.initial_quote + \
self._escape_identifier(value) + \
self.final_quote
def _requires_quotes(self, value):
"""Return True if the given identifier requires quoting."""
lc_value = value.lower()
return (lc_value in self.reserved_words
or value[0] in self.illegal_initial_characters
or not self.legal_characters.match(util.text_type(value))
or (lc_value != value))
def quote_schema(self, schema, force=None):
"""Conditionally quote a schema.
Subclasses can override this to provide database-dependent
quoting behavior for schema names.
the 'force' flag should be considered deprecated.
"""
return self.quote(schema, force)
def quote(self, ident, force=None):
"""Conditionally quote an identifier.
the 'force' flag should be considered deprecated.
"""
force = getattr(ident, "quote", None)
if force is None:
if ident in self._strings:
return self._strings[ident]
else:
if self._requires_quotes(ident):
self._strings[ident] = self.quote_identifier(ident)
else:
self._strings[ident] = ident
return self._strings[ident]
elif force:
return self.quote_identifier(ident)
else:
return ident
def format_sequence(self, sequence, use_schema=True):
name = self.quote(sequence.name)
if not self.omit_schema and use_schema and sequence.schema is not None:
name = self.quote_schema(sequence.schema) + "." + name
return name
def format_label(self, label, name=None):
return self.quote(name or label.name)
def format_alias(self, alias, name=None):
return self.quote(name or alias.name)
def format_savepoint(self, savepoint, name=None):
return self.quote(name or savepoint.ident)
def format_constraint(self, constraint):
return self.quote(constraint.name)
def format_table(self, table, use_schema=True, name=None):
"""Prepare a quoted table and schema name."""
if name is None:
name = table.name
result = self.quote(name)
if not self.omit_schema and use_schema \
and getattr(table, "schema", None):
result = self.quote_schema(table.schema) + "." + result
return result
def format_schema(self, name, quote=None):
"""Prepare a quoted schema name."""
return self.quote(name, quote)
def format_column(self, column, use_table=False,
name=None, table_name=None):
"""Prepare a quoted column name."""
if name is None:
name = column.name
if not getattr(column, 'is_literal', False):
if use_table:
return self.format_table(
column.table, use_schema=False,
name=table_name) + "." + self.quote(name)
else:
return self.quote(name)
else:
# literal textual elements get stuck into ColumnClause a lot,
# which shouldn't get quoted
if use_table:
return self.format_table(column.table,
use_schema=False, name=table_name) + '.' + name
else:
return name
def format_table_seq(self, table, use_schema=True):
"""Format table name and schema as a tuple."""
# Dialects with more levels in their fully qualified references
# ('database', 'owner', etc.) could override this and return
# a longer sequence.
if not self.omit_schema and use_schema and \
getattr(table, 'schema', None):
return (self.quote_schema(table.schema),
self.format_table(table, use_schema=False))
else:
return (self.format_table(table, use_schema=False), )
@util.memoized_property
def _r_identifiers(self):
initial, final, escaped_final = \
[re.escape(s) for s in
(self.initial_quote, self.final_quote,
self._escape_identifier(self.final_quote))]
r = re.compile(
r'(?:'
r'(?:%(initial)s((?:%(escaped)s|[^%(final)s])+)%(final)s'
r'|([^\.]+))(?=\.|$))+' %
{'initial': initial,
'final': final,
'escaped': escaped_final})
return r
def unformat_identifiers(self, identifiers):
"""Unpack 'schema.table.column'-like strings into components."""
r = self._r_identifiers
return [self._unescape_identifier(i)
for i in [a or b for a, b in r.findall(identifiers)]]
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