columns.jsonString()

When to use

• Your TypeScript code expects a typed object
• Your database stores the object as a JSON encoded string

Do not use when using a native JSON database column and the database driver returns a JavaScript object.

How it works

This column type is generic and takes a generic parameter of the object type stored in the database.

type MyStoredObject = {
  animal: string;
  canFly: boolean;
};

columns.jsonString<MyStoredObject>();

Nullability

If the column allows null values, use columns.jsonStringNull().

Example

Given the following database table animalExample:

id INT	attributes TEXT
1	'{"animal":"capybara","canFly":false}'
2	'{"animal":"magpie","canFly":true}'

And the following model:

type MyStoredObject = {
  animal: string;
  canFly: boolean;
};

const getExampleRow = db.getOne({
  name: "get-one-example-row",
  columns: {
    attributes: columns.jsonString<MyStoredObject>(),
  },
  query: ({ id }: { id: number }) =>
    SQL`SELECT pet FROM animalExample WHERE id = ${id}`,
});

A query for row id 1 yields:

const result = await getExampleRow({ id: 1 });
if (result) {
  console.log(result.attributes);
}

// -> { animal: 'capybara', canFly: false }