diff options
Diffstat (limited to 'lib/sqlalchemy/engine/default.py')
| -rw-r--r-- | lib/sqlalchemy/engine/default.py | 113 |
1 files changed, 110 insertions, 3 deletions
diff --git a/lib/sqlalchemy/engine/default.py b/lib/sqlalchemy/engine/default.py index 628e23c9e..d1b54ab01 100644 --- a/lib/sqlalchemy/engine/default.py +++ b/lib/sqlalchemy/engine/default.py @@ -552,6 +552,8 @@ class DefaultExecutionContext(interfaces.ExecutionContext): # result column names _translate_colname = None + _expanded_parameters = util.immutabledict() + @classmethod def _init_ddl(cls, dialect, connection, dbapi_connection, compiled_ddl): """Initialize execution context for a DDLElement construct.""" @@ -645,6 +647,11 @@ class DefaultExecutionContext(interfaces.ExecutionContext): processors = compiled._bind_processors + if compiled.contains_expanding_parameters: + positiontup = self._expand_in_parameters(compiled, processors) + elif compiled.positional: + positiontup = self.compiled.positiontup + # Convert the dictionary of bind parameter values # into a dict or list to be sent to the DBAPI's # execute() or executemany() method. @@ -652,7 +659,7 @@ class DefaultExecutionContext(interfaces.ExecutionContext): if compiled.positional: for compiled_params in self.compiled_parameters: param = [] - for key in self.compiled.positiontup: + for key in positiontup: if key in processors: param.append(processors[key](compiled_params[key])) else: @@ -684,10 +691,97 @@ class DefaultExecutionContext(interfaces.ExecutionContext): ) parameters.append(param) + self.parameters = dialect.execute_sequence_format(parameters) return self + def _expand_in_parameters(self, compiled, processors): + """handle special 'expanding' parameters, IN tuples that are rendered + on a per-parameter basis for an otherwise fixed SQL statement string. + + """ + if self.executemany: + raise exc.InvalidRequestError( + "'expanding' parameters can't be used with " + "executemany()") + + if self.compiled.positional and self.compiled._numeric_binds: + # I'm not familiar with any DBAPI that uses 'numeric' + raise NotImplementedError( + "'expanding' bind parameters not supported with " + "'numeric' paramstyle at this time.") + + self._expanded_parameters = {} + + compiled_params = self.compiled_parameters[0] + if compiled.positional: + positiontup = [] + else: + positiontup = None + + replacement_expressions = {} + for name in ( + self.compiled.positiontup if compiled.positional + else self.compiled.binds + ): + parameter = self.compiled.binds[name] + if parameter.expanding: + values = compiled_params.pop(name) + if not values: + raise exc.InvalidRequestError( + "'expanding' parameters can't be used with an " + "empty list" + ) + elif isinstance(values[0], (tuple, list)): + to_update = [ + ("%s_%s_%s" % (name, i, j), value) + for i, tuple_element in enumerate(values, 1) + for j, value in enumerate(tuple_element, 1) + ] + replacement_expressions[name] = ", ".join( + "(%s)" % ", ".join( + self.compiled.bindtemplate % { + "name": + to_update[i * len(tuple_element) + j][0] + } + for j, value in enumerate(tuple_element) + ) + for i, tuple_element in enumerate(values) + + ) + else: + to_update = [ + ("%s_%s" % (name, i), value) + for i, value in enumerate(values, 1) + ] + replacement_expressions[name] = ", ".join( + self.compiled.bindtemplate % { + "name": key} + for key, value in to_update + ) + compiled_params.update(to_update) + processors.update( + (key, processors[name]) + for key in to_update if name in processors + ) + if compiled.positional: + positiontup.extend(name for name, value in to_update) + self._expanded_parameters[name] = [ + expand_key for expand_key, value in to_update] + elif compiled.positional: + positiontup.append(name) + + def process_expanding(m): + return replacement_expressions.pop(m.group(1)) + + self.statement = re.sub( + r"\[EXPANDING_(.+)\]", + process_expanding, + self.statement + ) + return positiontup + @classmethod def _init_statement(cls, dialect, connection, dbapi_connection, statement, parameters): @@ -1039,7 +1133,11 @@ class DefaultExecutionContext(interfaces.ExecutionContext): get_dbapi_type(self.dialect.dbapi) if dbtype is not None and \ (not exclude_types or dbtype not in exclude_types): - inputsizes.append(dbtype) + if key in self._expanded_parameters: + inputsizes.extend( + [dbtype] * len(self._expanded_parameters[key])) + else: + inputsizes.append(dbtype) try: self.cursor.setinputsizes(*inputsizes) except BaseException as e: @@ -1054,10 +1152,19 @@ class DefaultExecutionContext(interfaces.ExecutionContext): if dbtype is not None and \ (not exclude_types or dbtype not in exclude_types): if translate: + # TODO: this part won't work w/ the + # expanded_parameters feature, e.g. for cx_oracle + # quoted bound names key = translate.get(key, key) if not self.dialect.supports_unicode_binds: key = self.dialect._encoder(key)[0] - inputsizes[key] = dbtype + if key in self._expanded_parameters: + inputsizes.update( + (expand_key, dbtype) for expand_key + in self._expanded_parameters[key] + ) + else: + inputsizes[key] = dbtype try: self.cursor.setinputsizes(**inputsizes) except BaseException as e: |