feat(database): Add user_id and dttm composite index to Log model. (#19532)

* feat: Added user_id and dttm composite index to Log model.

* fix: Refactored migration to a general view.

* fix: Changed down revision.

* fix: Formatted with black.

* fix: Removed odd Index import.

superset/migrations/versions/cdcf3d64daf4_add_user_id_dttm_idx_to_log_model.py

@@ -0,0 +1,40 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+"""Add user_id and dttm composite index to Log model
+
+Revision ID: cdcf3d64daf4
+Revises: b0d0249074e4
+Create Date: 2022-04-05 13:27:06.028908
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = "cdcf3d64daf4"
+down_revision = "b0d0249074e4"
+
+
+from alembic import op
+
+
+def upgrade():
+    op.create_index(
+        op.f("ix_logs_user_id_dttm"), "logs", ["user_id", "dttm"], unique=False
+    )
+
+
+def downgrade():
+    op.drop_index(op.f("ix_logs_user_id_dttm"), table_name="logs")