Constants, aliases & JOINs

The examples use full naming, tables users and posts, and a foreign key from posts.user_id to users.id.

Constants

use Tbl\Tbl;

Tbl::users;                 // 'users'
Tbl::users__id;             // 'id'
Tbl::fk__posts__users;      // 'user_id'
Tbl::on__posts__users;      // 'posts.user_id = users.id'

Columns are unqualified strings. When both joined tables have an id column, qualify it explicitly.

Table and column aliases

Tbl::users('u');             // 'users AS u'
Tbl::users__id('u');         // 'u.id'
Tbl::users__id(alias: 'u');  // 'u.id'
Tbl::users__id('users');     // 'users.id'

An alias is local to the call. Tbl::users('u') does not register u for subsequent calls.

Tbl::users__id();       // 'id'
Tbl::users__id(null);   // 'id'
Tbl::users__id('');     // 'id'

Table helpers return the original table name when no alias, null, or an empty string is supplied. Foreign key helpers behave like column helpers:

Tbl::fk__posts__users('p'); // 'p.user_id'

JOIN expressions

The first argument qualifies the referencing table; the second qualifies the referenced table:

Tbl::on__posts__users();          // 'posts.user_id = users.id'
Tbl::on__posts__users('p');       // 'p.user_id = users.id'
Tbl::on__posts__users(null, 'u'); // 'posts.user_id = u.id'
Tbl::on__posts__users('p', 'u');  // 'p.user_id = u.id'

Use positional arguments for JOIN helpers. Pass null to retain an endpoint's original table name.

Complete query

use Tbl\Tbl;

$sql = 'SELECT '
    . Tbl::users__id('u') . ' AS user_id, '
    . Tbl::posts__id('p') . ' AS post_id'
    . ' FROM ' . Tbl::users('u')
    . ' JOIN ' . Tbl::posts('p')
    . ' ON ' . Tbl::on__posts__users('p', 'u')
    . ' WHERE ' . Tbl::users__id('u') . ' = ?';

$statement = $pdo->prepare($sql);
$statement->execute([$userId]);

Aliases should come from your code. Helpers concatenate SQL fragments; they do not quote identifiers or bind values.

Self JOIN

Given users.parent_id referencing users.id:

Tbl::on__users__users('child', 'parent'); // 'child.parent_id = parent.id'

This allows the same table to appear twice with independent aliases.

Helper implementation

The generated class uses __callStatic without explicit per-column methods or a column lookup map. Constants remain available for IDE autocomplete. Calling an unknown helper throws BadMethodCallException.