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

```ts
type NullableColumnsToOptional<T> = {
  readonly [K in RequiredColumnKeys<T>]: StandardSchemaV1.InferOutput<T[K]>;
} & {
  readonly [K in OptionalColumnKeys<T>]?: StandardSchemaV1.InferOutput<T[K]>;
};
```

Defined in: [packages/common/src/local-first/Schema.ts:413](https://github.com/evoluhq/evolu/blob/037c390af081e9944d616ff298a729515c5c5ab7/packages/common/src/local-first/Schema.ts#L413)

Makes columns whose output type includes `null` optional.