[API reference](https://evolu.dev/docs/api-reference) › [@evolu/common](https://evolu.dev/docs/api-reference/common) › [local‑first/Query](https://evolu.dev/docs/api-reference/common/local-first/Query) › KyselyNotNull

```ts
type KyselyNotNull = {
  __notNull__: unique symbol;
};
```

Defined in: node_modules/.bun/kysely@0.28.15/node_modules/kysely/dist/esm/util/type-utils.d.ts:137

A type constant for marking a column as not null. Can be used with `$narrowPartial`.

Example:

```ts

await db
  .selectFrom("person")
  .where("nullable_column", "is not", null)
  .selectAll()
  .$narrowType<{ nullable_column: NotNull }>()
  .executeTakeFirstOrThrow();
```

## Properties

<a id="__notnull__"></a>

### \_\_notNull\_\_

```ts
readonly __notNull__: unique symbol;
```

Defined in: node_modules/.bun/kysely@0.28.15/node_modules/kysely/dist/esm/util/type-utils.d.ts:138