Limit

The limit method allows you to restrict the number of rows returned by your query. This is commonly used for performance optimization and controlling result set size.

Basic Usage

import { createQueryBuilder } from '@hypequery/clickhouse';

const db = createQueryBuilder<Schema>();

// Limit results to 10 rows
const query = db
  .table('users')
  .select(['id', 'name', 'email'])
  .limit(10)
  .toSQL();
// Result: SELECT id, name, email FROM users LIMIT 10

Type Definitions

limit(count: number): this

Parameters

• count: The maximum number of rows to return

Returns

Returns the query builder instance for method chaining.

Examples

Basic Limiting

// Limit to 5 users
const query = db
  .table('users')
  .select(['id', 'name'])
  .limit(5)
  .toSQL();
// Result: SELECT id, name FROM users LIMIT 5

Limit with Ordering

// Get top 10 users by creation date
const query = db
  .table('users')
  .select(['id', 'name', 'created_at'])
  .orderBy('created_at', 'DESC')
  .limit(10)
  .toSQL();
// Result: SELECT id, name, created_at FROM users ORDER BY created_at DESC LIMIT 10

Type Safety

The limit method provides basic TypeScript support:

interface UserSchema {
  users: {
    id: 'UInt32';
    name: 'String';
    email: 'String';
  };
}

const db = createQueryBuilder<UserSchema>();

// ✅ Valid limit value
const query = db
  .table('users')
  .select(['id', 'name'])
  .limit(10) // Positive integer
  .toSQL();

// ❌ TypeScript error for invalid limit
const query2 = db
  .table('users')
  .select(['id', 'name'])
  .limit(-5) // TypeScript error: negative number
  .toSQL();