# sql/compiler.py # Copyright (C) 2005-2013 the SQLAlchemy authors and contributors # # 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 import sys from .. import schema, engine, util, exc, types from . import ( operators, functions, util as sql_util, visitors, expression as sql ) import decimal import itertools 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 xrange(0, 10)]).union(['$']) BIND_PARAMS = re.compile(r'(? ', 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 = { sql.CompoundSelect.UNION: 'UNION', sql.CompoundSelect.UNION_ALL: 'UNION ALL', sql.CompoundSelect.EXCEPT: 'EXCEPT', sql.CompoundSelect.EXCEPT_ALL: 'EXCEPT ALL', sql.CompoundSelect.INTERSECT: 'INTERSECT', sql.CompoundSelect.INTERSECT_ALL: 'INTERSECT ALL' } 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 @property def quote(self): return self.element.quote class SQLCompiler(engine.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 = {} engine.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.iteritems(): 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, **kw): # only render labels within the columns clause # or ORDER BY clause of a select. dialect-specific compilers # can modify this behavior. if within_columns_clause and not within_label_clause: if isinstance(label.name, sql._truncated_label): labelname = self._truncated_identifier("colident", label.name) else: labelname = label.name 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) 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, sql._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, column.quote) 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, table.quote_schema) + '.' else: schema_prefix = '' tablename = table.name if isinstance(tablename, sql._truncated_label): tablename = self._truncated_identifier("alias", tablename) return schema_prefix + \ self.preparer.quote(tablename, table.quote) + \ "." + 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, **kwargs): if textclause.typemap is not None: for colname, type_ in textclause.typemap.iteritems(): self.result_map[colname if self.dialect.case_sensitive else colname.lower()] = \ (colname, None, type_) def do_bindparam(m): name = m.group(1) if name in textclause.bindparams: return self.process(textclause.bindparams[name]) else: return self.bindparam_string(name, **kwargs) # 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_null(self, expr, **kw): return 'NULL' def visit_true(self, expr, **kw): return 'true' def visit_false(self, expr, **kw): return 'false' def visit_clauselist(self, clauselist, **kwargs): sep = clauselist.operator if sep is None: sep = " " else: sep = OPERATORS[clauselist.operator] return sep.join( s for s in (c._compiler_dispatch(self, **kwargs) 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_binary(self, binary, **kw): # don't allow "? = ?" to render if self.ansi_bind_rules and \ isinstance(binary.left, sql.BindParameter) and \ isinstance(binary.right, sql.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 sql.literal_column("'%'", type_=types.String()) 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) return '%s LIKE %s' % ( binary.left._compiler_dispatch(self, **kw), binary.right._compiler_dispatch(self, **kw)) \ + (escape and (' ESCAPE ' + self.render_literal_value(escape, None)) or '') 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 and (' ESCAPE ' + self.render_literal_value(escape, None)) or '') 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 and (' ESCAPE ' + self.render_literal_value(escape, None)) or '') 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 and (' ESCAPE ' + self.render_literal_value(escape, None)) or '') 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: raise exc.CompileError("Bind parameter without a " "renderable value not allowed here.") 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, quote=bindparam.quote, **kwargs) def render_literal_bindparam(self, bindparam, **kw): value = bindparam.value processor = bindparam.type._cached_bind_processor(self.dialect) if processor: value = processor(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. """ if isinstance(value, basestring): value = value.replace("'", "''") return "'%s'" % value elif value is None: return "NULL" elif isinstance(value, (float, int, long)): return repr(value) elif isinstance(value, decimal.Decimal): return str(value) elif isinstance(value, util.binary_type): # only would occur on py3k b.c. on 2k the string_types # directive above catches this. # see #2838 value = value.decode(self.dialect.encoding).replace("'", "''") return "'%s'" % 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, sql._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, quote=None, 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, sql._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, sql._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, sql.Select): col_source = cte.original elif isinstance(cte.original, sql.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, sql._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, sql.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, sql.ColumnClause) and \ not column.is_literal and \ column.table is not None and \ not isinstance(column.table, sql.Select): result_expr = _CompileLabel(col_expr, sql._as_truncated(column.name), alt_names=(column.key,)) elif not isinstance(column, (sql.UnaryExpression, sql.TextClause)) \ and (not hasattr(column, 'name') or \ isinstance(column, sql.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, sql.ColumnClause) result_expr = _CompileLabel(col_expr, sql._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 _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, **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'] ) ) 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(sql._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.iteritems() 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: text += self.order_by_clause(select, **kwargs) if select._limit is not None or select._offset is not None: text += self.limit_clause(select) if select.for_update: 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): if select.for_update: return " FOR UPDATE" else: return "" 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(sql.literal(select._limit)) if select._offset is not None: if select._limit is None: text += "\n LIMIT -1" text += " OFFSET " + self.process(sql.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, table.quote_schema) + \ "." + self.preparer.quote(table.name, table.quote) else: ret = self.preparer.quote(table.name, table.quote) 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) 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, extra_froms) 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 update_stmt._returning: self.returning = update_stmt._returning if self.returning_precedes_values: text += " " + self.returning_clause( update_stmt, update_stmt._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, update_stmt._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 = sql.bindparam(name, value, type_=col.type, required=required, quote=col.quote) bindparam._is_crud = True return bindparam._compiler_dispatch(self) def _get_colparams(self, stmt, extra_tables=None): """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 # if we have statement parameters - set defaults in the # compiled params if self.column_keys is None: parameters = {} else: parameters = dict((sql._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.iteritems(): colkey = sql._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 sql._is_literal(v): v = self.process(sql.bindparam(None, v, type_=k.type)) else: v = self.process(v.self_group()) 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 postfetch_lastrowid = need_pks and self.dialect.postfetch_lastrowid check_columns = {} # special logic that only occurs for multi-table UPDATE # statements if extra_tables and stmt_parameters: normalized_params = dict( (sql._clause_element_as_expr(c), param) for c, param in stmt_parameters.items() ) assert self.isupdate affected_tables = set() for t in extra_tables: for c in t.c: if c in normalized_params: affected_tables.add(t) check_columns[c.key] = c value = normalized_params[c] if sql._is_literal(value): value = self._create_crud_bind_param( c, value, required=value is REQUIRED) else: self.postfetch.append(c) value = self.process(value.self_group()) 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())) ) 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: self.postfetch.append(c) # iterating through columns at the top to maintain ordering. # otherwise we might iterate through individual sets of # "defaults", "primary key cols", etc. for c in stmt.table.columns: if c.key in parameters and c.key not in check_columns: value = parameters.pop(c.key) if sql._is_literal(value): value = self._create_crud_bind_param( c, value, required=value is REQUIRED, name=c.key if not stmt._has_multi_parameters else "%s_0" % c.key ) elif c.primary_key and implicit_returning: self.returning.append(c) value = self.process(value.self_group()) else: self.postfetch.append(c) value = self.process(value.self_group()) 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) values.append((c, proc)) self.returning.append(c) elif c.default.is_clause_element: values.append( (c, self.process(c.default.arg.self_group())) ) 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 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) values.append((c, proc)) if not c.primary_key: self.postfetch.append(c) elif c.default.is_clause_element: values.append( (c, self.process(c.default.arg.self_group())) ) if 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 not c.primary_key: self.postfetch.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())) ) 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: self.postfetch.append(c) if parameters and stmt_parameters: check = set(parameters).intersection( sql._column_as_key(k) for k in stmt.parameters ).difference(check_columns) if check: raise exc.CompileError( "Unconsumed column names: %s" % (", ".join(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(engine.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, create.quote) return "CREATE SCHEMA " + schema def visit_drop_schema(self, drop): schema = self.preparer.format_schema(drop.element, drop.quote) 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, ce: # Py3K #raise exc.CompileError("(in table '%s', column '%s'): %s" # % ( # table.description, # column.name, # ce.args[0] # )) from ce # Py2K raise exc.CompileError("(in table '%s', column '%s'): %s" % ( table.description, column.name, ce.args[0] )), None, sys.exc_info()[2] # end Py2K 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, index.table.quote_schema) else: schema_name = None ident = index.name if isinstance(ident, sql._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, index.quote) 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, basestring): 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, c.quote) 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, f.parent.quote) for f in constraint._elements.values()), self.define_constraint_remote_table( constraint, remote_table, preparer), ', '.join(preparer.quote(f.column.name, f.column.quote) 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): text = "" if constraint.name is not None: text += "CONSTRAINT %s " % \ self.preparer.format_constraint(constraint) text += "UNIQUE (%s)" % ( ', '.join(self.preparer.quote(c.name, c.quote) 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(engine.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 NotImplementedError("Can't generate DDL for the null 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(unicode(value)) or (lc_value != value)) def quote_schema(self, schema, force): """Quote a schema. Subclasses should override this to provide database-dependent quoting behavior. """ return self.quote(schema, force) def quote(self, ident, force): 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, sequence.quote) if not self.omit_schema and use_schema and \ sequence.schema is not None: name = self.quote_schema(sequence.schema, sequence.quote) + \ "." + name return name def format_label(self, label, name=None): return self.quote(name or label.name, label.quote) def format_alias(self, alias, name=None): return self.quote(name or alias.name, alias.quote) def format_savepoint(self, savepoint, name=None): return self.quote(name or savepoint.ident, savepoint.quote) def format_constraint(self, constraint): return self.quote(constraint.name, constraint.quote) 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, table.quote) if not self.omit_schema and use_schema \ and getattr(table, "schema", None): result = self.quote_schema(table.schema, table.quote_schema) + \ "." + result return result def format_schema(self, name, quote): """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, column.quote) else: return self.quote(name, column.quote) 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, table.quote_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)]]