lol

venv/Lib/site-packages/sqlalchemy/dialects/mysql/base.py

@@ -999,14 +999,14 @@ output::
     )
 
 """  # noqa
+from __future__ import annotations
 
 from array import array as _array
 from collections import defaultdict
 from itertools import compress
 import re
+from typing import cast
 
-from sqlalchemy import literal_column
-from sqlalchemy.sql import visitors
 from . import reflection as _reflection
 from .enumerated import ENUM
 from .enumerated import SET
@@ -1047,10 +1047,12 @@ from .types import TINYTEXT
 from .types import VARCHAR
 from .types import YEAR
 from ... import exc
+from ... import literal_column
 from ... import log
 from ... import schema as sa_schema
 from ... import sql
 from ... import util
+from ...engine import cursor as _cursor
 from ...engine import default
 from ...engine import reflection
 from ...engine.reflection import ReflectionDefaults
@@ -1062,7 +1064,10 @@ from ...sql import operators
 from ...sql import roles
 from ...sql import sqltypes
 from ...sql import util as sql_util
+from ...sql import visitors
 from ...sql.compiler import InsertmanyvaluesSentinelOpts
+from ...sql.compiler import SQLCompiler
+from ...sql.schema import SchemaConst
 from ...types import BINARY
 from ...types import BLOB
 from ...types import BOOLEAN
@@ -1071,6 +1076,7 @@ from ...types import UUID
 from ...types import VARBINARY
 from ...util import topological
 
+
 SET_RE = re.compile(
     r"\s*SET\s+(?:(?:GLOBAL|SESSION)\s+)?\w", re.I | re.UNICODE
 )
@@ -1164,6 +1170,32 @@ ischema_names = {
 
 
 class MySQLExecutionContext(default.DefaultExecutionContext):
+    def post_exec(self):
+        if (
+            self.isdelete
+            and cast(SQLCompiler, self.compiled).effective_returning
+            and not self.cursor.description
+        ):
+            # All MySQL/mariadb drivers appear to not include
+            # cursor.description for DELETE..RETURNING with no rows if the
+            # WHERE criteria is a straight "false" condition such as our EMPTY
+            # IN condition. manufacture an empty result in this case (issue
+            # #10505)
+            #
+            # taken from cx_Oracle implementation
+            self.cursor_fetch_strategy = (
+                _cursor.FullyBufferedCursorFetchStrategy(
+                    self.cursor,
+                    [
+                        (entry.keyname, None)
+                        for entry in cast(
+                            SQLCompiler, self.compiled
+                        )._result_columns
+                    ],
+                    [],
+                )
+            )
+
     def create_server_side_cursor(self):
         if self.dialect.supports_server_side_cursors:
             return self._dbapi_connection.cursor(self.dialect._sscursor)
@@ -1208,6 +1240,12 @@ class MySQLCompiler(compiler.SQLCompiler):
         )
         return f"{clause} WITH ROLLUP"
 
+    def visit_aggregate_strings_func(self, fn, **kw):
+        expr, delimeter = (
+            elem._compiler_dispatch(self, **kw) for elem in fn.clauses
+        )
+        return f"group_concat({expr} SEPARATOR {delimeter})"
+
     def visit_sequence(self, seq, **kw):
         return "nextval(%s)" % self.preparer.format_sequence(seq)
 
@@ -1760,7 +1798,12 @@ class MySQLCompiler(compiler.SQLCompiler):
 class MySQLDDLCompiler(compiler.DDLCompiler):
     def get_column_specification(self, column, **kw):
         """Builds column DDL."""
-
+        if (
+            self.dialect.is_mariadb is True
+            and column.computed is not None
+            and column._user_defined_nullable is SchemaConst.NULL_UNSPECIFIED
+        ):
+            column.nullable = True
         colspec = [
             self.preparer.format_column(column),
             self.dialect.type_compiler_instance.process(