{
  "name": "01_create_tables",
  "operations": [
    {
      "create_table": {
        "name": "customers",
        "columns": [
          {
            "name": "id",
            "type": "integer",
            "pk": true
          },
          {
            "name": "name",
            "type": "varchar(255)",
            "unique": true
          },
          {
            "name": "credit_card",
            "type": "text",
            "nullable": true
          }
        ]
      }
    },
    {
      "create_table": {
        "name": "bills",
        "columns": [
          {
            "name": "id",
            "type": "integer",
            "pk": true
          },
          {
            "name": "date",
            "type": "time with time zone"
          },
          {
            "name": "quantity",
            "type": "integer"
          }
        ]
      }
    }
  ]
}