diff options
Diffstat (limited to 'lib/sqlalchemy/sql/compiler.py')
| -rw-r--r-- | lib/sqlalchemy/sql/compiler.py | 34 |
1 files changed, 24 insertions, 10 deletions
diff --git a/lib/sqlalchemy/sql/compiler.py b/lib/sqlalchemy/sql/compiler.py index 51664d64e..ac46d5768 100644 --- a/lib/sqlalchemy/sql/compiler.py +++ b/lib/sqlalchemy/sql/compiler.py @@ -109,6 +109,22 @@ FUNCTIONS = { functions.user: 'USER' } + +class _CompileLabel(object): + """lightweight label object which acts as an expression._Label.""" + + __metaclass__ = sql._FigureVisitName + __visit_name__ = 'label' + __slots__ = 'element', 'name' + + def __init__(self, col, name): + self.element = col + self.name = name + + @property + def quote(self): + return self.element.quote + class DefaultCompiler(engine.Compiled): """Default implementation of Compiled. @@ -175,9 +191,7 @@ class DefaultCompiler(engine.Compiled): self.string = self.process(self.statement) def process(self, obj, **kwargs): - meth = getattr(self, "visit_%s" % obj.__visit_name__, None) - if meth: - return meth(obj, **kwargs) + return obj._compiler_dispatch(self, **kwargs) def is_subquery(self): return self.stack and len(self.stack) > 1 and self.stack[-1].get('from') @@ -243,8 +257,8 @@ class DefaultCompiler(engine.Compiled): if result_map is not None: result_map[name.lower()] = (name, (column, ), column.type) - - if getattr(column, "is_literal", False): + + if column.is_literal: name = self.escape_literal_column(name) else: name = self.preparer.quote(name, column.quote) @@ -252,7 +266,7 @@ class DefaultCompiler(engine.Compiled): if column.table is None or not column.table.named_with_column: return name else: - if getattr(column.table, 'schema', None): + if column.table.schema: schema_prefix = self.preparer.quote(column.table.schema, column.table.quote_schema) + '.' else: schema_prefix = '' @@ -432,8 +446,8 @@ class DefaultCompiler(engine.Compiled): if isinstance(column, sql._Label): return column - if select.use_labels and getattr(column, '_label', None): - return column.label(column._label) + if select.use_labels and column._label: + return _CompileLabel(column, column._label) if \ asfrom and \ @@ -441,9 +455,9 @@ class DefaultCompiler(engine.Compiled): not column.is_literal and \ column.table is not None and \ not isinstance(column.table, sql.Select): - return column.label(column.name) + return _CompileLabel(column, column.name) elif not isinstance(column, (sql._UnaryExpression, sql._TextClause, sql._BindParamClause)) and (not hasattr(column, 'name') or isinstance(column, sql._Function)): - return column.label(column.anon_label) + return _CompileLabel(column, column.anon_label) else: return column |