Sqler class

SQL Query Builder Library for MySQL

This library provides a comprehensive set of classes for building SQL queries programmatically using a fluent interface. It supports all major SQL operations including SELECT, INSERT, UPDATE, DELETE, and complex operations like JOINs, subqueries, and conditional expressions.

Key features:

• Fluent interface with method chaining
• Type-safe query construction
• Support for parameterized queries
• Comprehensive WHERE clause building
• JOIN operations (INNER, LEFT, RIGHT)
• Aggregate functions and mathematical expressions
• CASE statements and subqueries
• Proper SQL escaping and formatting

Main classes:

• Sqler: The main query builder class
• QField: Represents database fields with proper quoting
• QVar: Represents values with proper escaping
• Where: Base class for WHERE conditions
• Join: Represents JOIN operations
• QOrder: Represents ORDER BY specifications

Example usage:

var query = Sqler()
  .addSelect(QSelect('users.name'))
  .addSelect(QSelect('profiles.bio'))
  .from(QField('users'))
  .join(LeftJoin('profiles', On([
    Condition(QField('users.id'), QO.EQ, QField('profiles.user_id'))
  ])))
  .where(WhereOne(QField('users.active'), QO.EQ, QVar(true)))
  .orderBy(QOrder('users.name'))
  .limit(10);

String sql = query.toSQL();
// Generates: SELECT `users`.`name`, `profiles`.`bio` FROM `users`
//           LEFT JOIN `profiles` ON ( ( `users`.`id` = `profiles`.`user_id` ) )
//           WHERE ( `users`.`active` = true ) ORDER BY `users`.`name` ASC LIMIT 10

A SQL query builder for MySQL that provides a fluent interface for constructing SQL statements including SELECT, INSERT, UPDATE, and DELETE operations.

The Sqler class implements the builder pattern, allowing method chaining to construct complex SQL queries programmatically. It supports all major SQL operations including joins, where clauses, grouping, ordering, and parameterized queries.

Example usage:

var query = Sqler()
  .addSelect(QSelect('name'))
  .addSelect(QSelect('email'))
  .from(QField('users'))
  .where(WhereOne(QField('active'), QO.EQ, QVar(true)))
  .orderBy(QOrder('name'))
  .limit(10);

String sql = query.toSQL(); // Generates: SELECT `name`, `email` FROM `users` WHERE ( `active` = true ) ORDER BY `name` ASC LIMIT 10