Type alias InferTableSchema<T>

Automagically extracts a table's schema from some Table-like type, most useful when performing a Db.createTable (or Table.alter) operation.

You can think of it as similar to Zod or arktype's infer<Schema> types.

Accepts various different (contextually) isomorphic types to account for differences in instantiation & usage:

• CreateTableDefinition
• (...) => Promise<Table<infer Schema>>
• (...) => Table<infer Schema>
• Promise<Table<infer Schema>>
• Table<infer Schema>

A DB's type information is inferred by db.createTable by default. To override this behavior, please provide the table's type explicitly to help with transpilation times (e.g. db.createTable<SomeRow>(...)).

Example

const mkUserTable = () => db.createTable('users', {
  definition: {
    columns: {
      name: 'text',
      dob: {
        type: 'timestamp',
      },
      friends: {
        type: 'set',
        valueType: 'text',
      },
    },
    primaryKey: {
      partitionBy: ['name', 'height'],
      partitionSort: { dob: 1 },
    },
  },
});

// Type inference is as simple as that
type User = InferTableSchema<typeof mkUserTable>;
type UserPK = InferTablePrimaryKey<typeof mkUserTable>;

// Utility types for demonstration purposes
type Equal<X, Y> = (<T>() => T extends X ? 1 : 2) extends (<T>() => T extends Y ? 1 : 2) ? true : false;
type Expect<T extends true> = T;

// User evaluates to this object representing its TS representation
// for the table's schema
type _Proof = Equal<User, {
  name: string,
  dob: DataAPITimestamp,
  friends: Set<string>,
}>;

// UserPK evaluates to this object representing its TS representation
// for `insert*` operations' return types
type _ProofPK = Equal<UserPK, {
  name: string,
  height: TypeErr<'Field `height` not found as property in table definition'>,
  dob: DataAPITimestamp,
}>;

// And now `User` can be used wherever.
const main = async () => {
  const table: Table<User> = await mkUserTable();
  const found: User | null = await table.findOne({});
};
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