Implement database migration

backend/migrations/env.py

@@ -0,0 +1,43 @@
+from __future__ import annotations
+from sqlalchemy import engine_from_config, pool
+from alembic import context
+from models import Base
+
+config = context.config
+target_metadata = Base.metadata
+
+
+def _skip_empty_autogenerate(ctx, rev, directives):
+    # Avoid creating empty migrations when there are no schema changes
+    if getattr(config, "cmd_opts", None) and getattr(config.cmd_opts, "autogenerate", False):
+        if directives:
+            script = directives[0]
+            if hasattr(script, "upgrade_ops") and script.upgrade_ops.is_empty():
+                directives[:] = []
+
+def run_migrations_offline():
+    url = config.get_main_option("sqlalchemy.url")
+    context.configure(
+        url=url, target_metadata=target_metadata, literal_binds=True, dialect_opts={"paramstyle": "named"},
+        render_as_batch=True,
+        process_revision_directives=_skip_empty_autogenerate
+    )
+    with context.begin_transaction():
+        context.run_migrations()
+
+def run_migrations_online():
+    connectable = engine_from_config(config.get_section(config.config_ini_section) or {}, prefix="sqlalchemy.", poolclass=pool.NullPool)
+    with connectable.connect() as connection:
+        context.configure(
+            connection=connection,
+            target_metadata=target_metadata,
+            render_as_batch=True,
+            process_revision_directives=_skip_empty_autogenerate
+        )
+        with context.begin_transaction():
+            context.run_migrations()
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()