diff options
Diffstat (limited to 'lib/sqlalchemy/dialects')
| -rw-r--r-- | lib/sqlalchemy/dialects/mysql/base.py | 39 |
1 files changed, 23 insertions, 16 deletions
diff --git a/lib/sqlalchemy/dialects/mysql/base.py b/lib/sqlalchemy/dialects/mysql/base.py index e89ebb09d..1a0534490 100644 --- a/lib/sqlalchemy/dialects/mysql/base.py +++ b/lib/sqlalchemy/dialects/mysql/base.py @@ -1013,7 +1013,6 @@ from itertools import compress import re from sqlalchemy import literal_column -from sqlalchemy import text from sqlalchemy.sql import visitors from . import reflection as _reflection from .enumerated import ENUM @@ -1070,7 +1069,6 @@ from ...sql import operators from ...sql import roles from ...sql import sqltypes from ...sql import util as sql_util -from ...sql.sqltypes import Unicode from ...types import BINARY from ...types import BLOB from ...types import BOOLEAN @@ -2671,21 +2669,30 @@ class MySQLDialect(default.DefaultDialect): if schema is None: schema = self.default_schema_name - rs = connection.execute( - text( - "SELECT COUNT(*) FROM information_schema.tables WHERE " - "table_schema = :table_schema AND " - "table_name = :table_name" - ).bindparams( - sql.bindparam("table_schema", type_=Unicode), - sql.bindparam("table_name", type_=Unicode), - ), - { - "table_schema": str(schema), - "table_name": str(table_name), - }, + assert schema is not None + + full_name = ".".join( + self.identifier_preparer._quote_free_identifiers( + schema, table_name + ) ) - return bool(rs.scalar()) + + # DESCRIBE *must* be used because there is no information schema + # table that returns information on temp tables that is consistently + # available on MariaDB / MySQL / engine-agnostic etc. + # therefore we have no choice but to use DESCRIBE and an error catch + # to detect "False". See issue #9058 + + try: + with connection.exec_driver_sql( + f"DESCRIBE {full_name}", + execution_options={"skip_user_error_events": True}, + ) as rs: + return rs.fetchone() is not None + except exc.DBAPIError as e: + if self._extract_error_code(e.orig) == 1146: + return False + raise @reflection.cache def has_sequence(self, connection, sequence_name, schema=None, **kw): |