Add migration for Book

alembic/versions/20250325_172757_033ff255_create_book.py

@@ -0,0 +1,53 @@
+"""create books table
+
+Revision ID: 1234567890ab
+Revises: 
+Create Date: 2023-05-25 10:00:00.000000
+
+"""
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects.postgresql import UUID
+
+
+# revision identifiers, used by Alembic
+revision = '1234567890ab'
+down_revision = None
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    op.create_table(
+        'books',
+        sa.Column('id', UUID(as_uuid=True), primary_key=True, server_default=sa.text("uuid_generate_v4()")),
+        sa.Column('title', sa.String, nullable=False, index=True),
+        sa.Column('author', sa.String, nullable=False, index=True),
+        sa.Column('description', sa.String, nullable=True),
+        sa.Column('author_id', UUID(as_uuid=True), nullable=False),
+        sa.Column('created_at', sa.TIMESTAMP(timezone=True), nullable=False, server_default=sa.func.now()),
+        sa.Column('updated_at', sa.TIMESTAMP(timezone=True), nullable=False, server_default=sa.func.now(), onupdate=sa.func.now()),
+        sa.ForeignKeyConstraint(['author_id'], ['authors.id'], ondelete='CASCADE'),
+    )
+    op.create_index('idx_books_title_author', 'books', ['title', 'author'], unique=True)
+
+
+def downgrade():
+    op.drop_index('idx_books_title_author', 'books')
+    op.drop_table('books')
+
+```
+
+This Alembic migration script creates a new table called `books` with the following columns:
+
+- `id` (UUID, primary key, generated using `uuid_generate_v4()`)
+- `title` (String, not nullable, indexed)
+- `author` (String, not nullable, indexed)
+- `description` (String, nullable)
+- `author_id` (UUID, not nullable, foreign key referencing `authors.id` table with `ON DELETE CASCADE`)
+- `created_at` (TIMESTAMP with timezone, not nullable, default to current time)
+- `updated_at` (TIMESTAMP with timezone, not nullable, default to current time, updated on each row update)
+
+It also creates a unique index on the `title` and `author` columns combined.
+
+The `downgrade()` function removes the index and drops the `books` table.