Derive types from a relational query builder

Reuse the argument, filter, ordering, and SQL-result types that Drizzle already inferred for a table.

Import the type helpers

import type {
  InferFindFirstArgs,
  InferFindManyArgs,
  InferOrderBy,
  InferRelations,
  InferRelationsFilter,
} from 'drizzle-plus/types'

Pass a db.query.<table> builder to derive its types:

type UserFilter = InferRelationsFilter<typeof db.query.user>
type UserRelations = InferRelations<typeof db.query.user>
type UserOrderBy = InferOrderBy<typeof db.query.user>
type UserListArgs = InferFindManyArgs<typeof db.query.user>
type UserItemArgs = InferFindFirstArgs<typeof db.query.user>

These types are useful at application boundaries where a filter or query config is assembled before the final database call:

function listUsers(where: UserFilter, orderBy?: UserOrderBy) {
  return db.query.user.findMany({ where, orderBy })
}

Describe SQL inputs and results

The same module includes types for SQL helpers and scalar subqueries:

Type	Use it for
SQLValue<T>	A value or SQL expression that produces T.
SQLExpression<T>	A column or SQL wrapper producing T.
SQLResult<T>	The value returned by an expression, including nullable columns.
QueryToResult<T>	The result shape of a select or query promise.
QueryToSQL<T>	A query converted to a scalar SQL expression.
ReturningClause<T>	A typed returning selection for a table.

Prefer these helpers when a utility accepts a Drizzle query object rather than when a concrete application function can simply infer its parameters.