Add alembic for unique constraints

karp-backend/src/karp/main/migrations/versions/44229cf4d74b_add_unique_constraints_for_entries_.py

@@ -0,0 +1,28 @@
+"""Add unique constraints for entries tables.
+
+Revision ID: 44229cf4d74b
+Revises: e09588a7e6ca
+Create Date: 2024-02-05 11:29:56.613345
+
+"""
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import mysql
+
+# revision identifiers, used by Alembic.
+revision = '44229cf4d74b'
+down_revision = 'e09588a7e6ca'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    conn = op.get_bind()
+    for resource_id, table_name in conn.execute(
+        sa.text("select distinct resource_id, table_name from resources")
+    ):
+        op.execute(f"alter table {table_name} drop constraint if exists id_version_unique_constraint")
+        op.create_unique_constraint(
+            "id_version_unique_constraint",
+            table_name,
+            ["entity_id", "version"])