XOOPS Query Builder

The XOOPS Query Builder provides a modern, fluent interface for building SQL queries. It helps prevent SQL injection, improves readability, and provides database abstraction for multiple database systems.

Query Builder Architecture

graph TD
    A[QueryBuilder] -->|builds| B[SELECT Queries]
    A -->|builds| C[INSERT Queries]
    A -->|builds| D[UPDATE Queries]
    A -->|builds| E[DELETE Queries]

    F[Table] -->|chains| G[select]
    F -->|chains| H[where]
    F -->|chains| I[orderBy]
    F -->|chains| J[limit]

    G -->|chains| K[join]
    G -->|chains| H
    H -->|chains| I
    I -->|chains| J

    L[Execute Methods] -->|returns| M[Results]
    L -->|returns| N[Count]
    L -->|returns| O[First/Last]

QueryBuilder Class

The main query builder class with fluent interface.

Class Overview

namespace Xoops\Database;

class QueryBuilder
{
    protected string $table = '';
    protected string $type = 'SELECT';
    protected array $selects = [];
    protected array $joins = [];
    protected array $wheres = [];
    protected array $orders = [];
    protected int $limit = 0;
    protected int $offset = 0;
    protected array $bindings = [];
}

Static Methods

table

Creates a new query builder for a table.

public static function table(string $table): QueryBuilder

Parameters:

Parameter	Type	Description
$table	string	Table name (with or without prefix)

Returns: QueryBuilder - Query builder instance

Example:

$query = QueryBuilder::table('users');
$query = QueryBuilder::table('xoops_users'); // With prefix

SELECT Queries

select

Specifies columns to select.

public function select(...$columns): self

Parameters:

Parameter	Type	Description
...$columns	array	Column names or expressions

Returns: self - For method chaining

Example:

// Simple select
QueryBuilder::table('users')
    ->select('id', 'username', 'email')
    ->get();

// Select with aliases
QueryBuilder::table('users')
    ->select('id as user_id', 'username as name')
    ->get();

// Select all columns
QueryBuilder::table('users')
    ->select('*')
    ->get();

// Select with expressions
QueryBuilder::table('orders')
    ->select('id', 'COUNT(*) as total_items')
    ->groupBy('id')
    ->get();

where

Adds a WHERE condition.

public function where(string $column, string $operator = '=', mixed $value = null): self

Parameters:

Parameter	Type	Description
$column	string	Column name
$operator	string	Comparison operator
$value	mixed	Value to compare

Returns: self - For method chaining

Operators:

Operator	Description	Example
=	Equal	->where('status', '=', 'active')
!= or <>	Not equal	->where('status', '!=', 'deleted')
>	Greater than	->where('price', '>', 100)
<	Less than	->where('price', '<', 100)
>=	Greater or equal	->where('age', '>=', 18)
<=	Less or equal	->where('age', '<=', 65)
LIKE	Pattern match	->where('name', 'LIKE', '%john%')
IN	In list	->where('status', 'IN', ['active', 'pending'])
NOT IN	Not in list	->where('id', 'NOT IN', [1, 2, 3])
BETWEEN	Range	->where('age', 'BETWEEN', [18, 65])
IS NULL	Is null	->where('deleted_at', 'IS NULL')
IS NOT NULL	Not null	->where('deleted_at', 'IS NOT NULL')

Example:

// Single condition
QueryBuilder::table('users')
    ->select('*')
    ->where('status', '=', 'active')
    ->get();

// Multiple conditions (AND)
QueryBuilder::table('users')
    ->select('*')
    ->where('status', '=', 'active')
    ->where('age', '>=', 18)
    ->get();

// IN operator
QueryBuilder::table('products')
    ->select('*')
    ->where('category_id', 'IN', [1, 2, 3])
    ->get();

// LIKE operator
QueryBuilder::table('users')
    ->select('*')
    ->where('email', 'LIKE', '%@example.com')
    ->get();

// NULL check
QueryBuilder::table('users')
    ->select('*')
    ->where('deleted_at', 'IS NULL')
    ->get();

orWhere

Adds an OR condition.

public function orWhere(string $column, string $operator = '=', mixed $value = null): self

Example:

QueryBuilder::table('users')
    ->select('*')
    ->where('status', '=', 'active')
    ->orWhere('premium', '=', 1)
    ->get();
    // SELECT * FROM users WHERE status = 'active' OR premium = 1

whereIn / whereNotIn

Convenience methods for IN/NOT IN.

public function whereIn(string $column, array $values): self
public function whereNotIn(string $column, array $values): self

Example:

QueryBuilder::table('posts')
    ->select('*')
    ->whereIn('status', ['published', 'scheduled'])
    ->get();

QueryBuilder::table('comments')
    ->select('*')
    ->whereNotIn('spam_score', [8, 9, 10])
    ->get();

whereNull / whereNotNull

Convenience methods for NULL checks.

public function whereNull(string $column): self
public function whereNotNull(string $column): self

Example:

QueryBuilder::table('users')
    ->select('*')
    ->whereNotNull('verified_at')
    ->get();

whereBetween

Checks if value is between two values.

public function whereBetween(string $column, array $values): self

Example:

QueryBuilder::table('products')
    ->select('*')
    ->whereBetween('price', [10, 100])
    ->get();

QueryBuilder::table('orders')
    ->select('*')
    ->whereBetween('created_at', ['2024-01-01', '2024-12-31'])
    ->get();

join

Adds an INNER JOIN.

public function join(
    string $table,
    string $first,
    string $operator = '=',
    string $second = null
): self

Example:

QueryBuilder::table('posts')
    ->select('posts.*', 'users.username', 'categories.name')
    ->join('users', 'posts.user_id', '=', 'users.id')
    ->join('categories', 'posts.category_id', '=', 'categories.id')
    ->where('posts.published', '=', 1)
    ->get();

leftJoin / rightJoin

Alternative join types.

public function leftJoin(
    string $table,
    string $first,
    string $operator = '=',
    string $second = null
): self

public function rightJoin(
    string $table,
    string $first,
    string $operator = '=',
    string $second = null
): self

Example:

QueryBuilder::table('users')
    ->select('users.*', 'COUNT(posts.id) as post_count')
    ->leftJoin('posts', 'users.id', '=', 'posts.user_id')
    ->groupBy('users.id')
    ->get();

groupBy

Groups results by column(s).

public function groupBy(...$columns): self

Example:

QueryBuilder::table('orders')
    ->select('user_id', 'COUNT(*) as order_count', 'SUM(total) as total_spent')
    ->groupBy('user_id')
    ->get();

QueryBuilder::table('sales')
    ->select('department', 'region', 'SUM(amount) as total')
    ->groupBy('department', 'region')
    ->get();

having

Adds a HAVING condition.

public function having(string $column, string $operator = '=', mixed $value = null): self

Example:

QueryBuilder::table('orders')
    ->select('user_id', 'COUNT(*) as order_count')
    ->groupBy('user_id')
    ->having('order_count', '>', 5)
    ->get();

orderBy

Orders results.

public function orderBy(string $column, string $direction = 'ASC'): self

Parameters:

Parameter	Type	Description
$column	string	Column to order by
$direction	string	ASC or DESC

Example:

// Single order
QueryBuilder::table('users')
    ->select('*')
    ->orderBy('created_at', 'DESC')
    ->get();

// Multiple orders
QueryBuilder::table('posts')
    ->select('*')
    ->orderBy('category_id', 'ASC')
    ->orderBy('created_at', 'DESC')
    ->get();

// Random order
QueryBuilder::table('quotes')
    ->select('*')
    ->orderBy('RAND()')
    ->get();

limit / offset

Limits and offsets results.

public function limit(int $limit): self
public function offset(int $offset): self

Example:

// Simple limit
QueryBuilder::table('posts')
    ->select('*')
    ->limit(10)
    ->get();

// Pagination
$page = 2;
$perPage = 20;
$offset = ($page - 1) * $perPage;

QueryBuilder::table('posts')
    ->select('*')
    ->limit($perPage)
    ->offset($offset)
    ->get();

Execution Methods

get

Executes query and returns all results.

public function get(): array

Returns: array - Array of result rows

Example:

$users = QueryBuilder::table('users')
    ->select('id', 'username', 'email')
    ->where('status', '=', 'active')
    ->orderBy('username')
    ->get();

foreach ($users as $user) {
    echo $user['username'] . ' (' . $user['email'] . ')' . "\n";
}

first

Gets the first result.

public function first(): ?array

Returns: ?array - First row or null

Example:

$user = QueryBuilder::table('users')
    ->select('*')
    ->where('id', '=', 123)
    ->first();

if ($user) {
    echo 'Found: ' . $user['username'];
}

last

Gets the last result.

public function last(): ?array

Example:

$latestPost = QueryBuilder::table('posts')
    ->select('*')
    ->orderBy('created_at', 'DESC')
    ->last();

count

Gets the count of results.

public function count(): int

Returns: int - Number of rows

Example:

$activeUsers = QueryBuilder::table('users')
    ->where('status', '=', 'active')
    ->count();

echo "Active users: $activeUsers";

exists

Checks if query returns any results.

public function exists(): bool

Returns: bool - True if results exist

Example:

if (QueryBuilder::table('users')->where('email', '=', 'test@example.com')->exists()) {
    echo 'User already exists';
}

aggregate

Gets aggregate values.

public function aggregate(string $function, string $column): mixed

Example:

$maxPrice = QueryBuilder::table('products')
    ->aggregate('MAX', 'price');

$avgAge = QueryBuilder::table('users')
    ->aggregate('AVG', 'age');

$totalSales = QueryBuilder::table('orders')
    ->aggregate('SUM', 'total');

INSERT Queries

insert

Inserts a row.

public function insert(array $values): bool

Example:

QueryBuilder::table('users')->insert([
    'username' => 'john',
    'email' => 'john@example.com',
    'password' => password_hash('secret', PASSWORD_BCRYPT),
    'created_at' => date('Y-m-d H:i:s')
]);

insertMany

Inserts multiple rows.

public function insertMany(array $rows): bool

Example:

QueryBuilder::table('log_entries')->insertMany([
    ['action' => 'login', 'user_id' => 1, 'timestamp' => time()],
    ['action' => 'logout', 'user_id' => 2, 'timestamp' => time()],
    ['action' => 'update', 'user_id' => 3, 'timestamp' => time()]
]);

UPDATE Queries

update

Updates rows.

public function update(array $values): int

Returns: int - Number of affected rows

Example:

// Update single user
QueryBuilder::table('users')
    ->where('id', '=', 123)
    ->update([
        'email' => 'newemail@example.com',
        'updated_at' => date('Y-m-d H:i:s')
    ]);

// Update multiple rows
QueryBuilder::table('posts')
    ->where('status', '=', 'draft')
    ->where('created_at', '<', date('Y-m-d', strtotime('-30 days')))
    ->update([
        'status' => 'archived'
    ]);

increment / decrement

Increments or decrements a column.

public function increment(string $column, int $amount = 1): int
public function decrement(string $column, int $amount = 1): int

Example:

// Increment view count
QueryBuilder::table('posts')
    ->where('id', '=', 123)
    ->increment('views');

// Decrement stock
QueryBuilder::table('products')
    ->where('id', '=', 456)
    ->decrement('stock', 5);

DELETE Queries

delete

Deletes rows.

public function delete(): int

Returns: int - Number of deleted rows

Example:

// Delete single record
QueryBuilder::table('comments')
    ->where('id', '=', 789)
    ->delete();

// Delete multiple records
QueryBuilder::table('log_entries')
    ->where('created_at', '<', date('Y-m-d', strtotime('-30 days')))
    ->delete();

truncate

Deletes all rows from table.

public function truncate(): bool

Example:

// Clear all sessions
QueryBuilder::table('sessions')->truncate();

Advanced Features

Raw Expressions

QueryBuilder::table('products')
    ->select('id', 'name', QueryBuilder::raw('price * quantity as total'))
    ->get();

Subqueries

$recentPostIds = QueryBuilder::table('posts')
    ->select('id')
    ->where('created_at', '>', date('Y-m-d', strtotime('-7 days')))
    ->toSql();

$comments = QueryBuilder::table('comments')
    ->select('*')
    ->whereIn('post_id', $recentPostIds)
    ->get();

Getting the SQL

public function toSql(): string

Example:

$sql = QueryBuilder::table('users')
    ->select('id', 'username')
    ->where('status', '=', 'active')
    ->toSql();

echo $sql;
// SELECT id, username FROM xoops_users WHERE status = ?

Complete Examples

Complex Select with Joins

<?php
/**
 * Get posts with author and category info
 */

$posts = QueryBuilder::table('posts')
    ->select(
        'posts.id',
        'posts.title',
        'posts.content',
        'posts.created_at',
        'users.username as author',
        'categories.name as category'
    )
    ->join('users', 'posts.user_id', '=', 'users.id')
    ->join('categories', 'posts.category_id', '=', 'categories.id')
    ->where('posts.published', '=', 1)
    ->orderBy('posts.created_at', 'DESC')
    ->limit(10)
    ->get();

foreach ($posts as $post) {
    echo '<article>';
    echo '<h2>' . htmlspecialchars($post['title']) . '</h2>';
    echo '<p class="meta">By ' . htmlspecialchars($post['author']) . ' in ' . htmlspecialchars($post['category']) . '</p>';
    echo '<p>' . htmlspecialchars($post['content']) . '</p>';
    echo '</article>';
}

Pagination with QueryBuilder

<?php
/**
 * Paginated results
 */

$page = isset($_GET['page']) ? (int)$_GET['page'] : 1;
$perPage = 20;
$offset = ($page - 1) * $perPage;

// Get total count
$total = QueryBuilder::table('articles')
    ->where('status', '=', 'published')
    ->count();

// Get page results
$articles = QueryBuilder::table('articles')
    ->select('*')
    ->where('status', '=', 'published')
    ->orderBy('created_at', 'DESC')
    ->limit($perPage)
    ->offset($offset)
    ->get();

// Calculate pagination
$pages = ceil($total / $perPage);

// Display results
foreach ($articles as $article) {
    echo '<div class="article">' . htmlspecialchars($article['title']) . '</div>';
}

// Display pagination links
if ($pages > 1) {
    echo '<nav class="pagination">';
    for ($i = 1; $i <= $pages; $i++) {
        if ($i == $page) {
            echo '<span class="current">' . $i . '</span>';
        } else {
            echo '<a href="?page=' . $i . '">' . $i . '</a>';
        }
    }
    echo '</nav>';
}

Data Analysis with Aggregates

<?php
/**
 * Sales analysis
 */

// Total sales by region
$regionSales = QueryBuilder::table('orders')
    ->select('region', QueryBuilder::raw('SUM(total) as total_sales'), QueryBuilder::raw('COUNT(*) as order_count'))
    ->groupBy('region')
    ->orderBy('total_sales', 'DESC')
    ->get();

foreach ($regionSales as $region) {
    echo $region['region'] . ': $' . number_format($region['total_sales'], 2) . ' (' . $region['order_count'] . ' orders)' . "\n";
}

// Average order value
$avgOrderValue = QueryBuilder::table('orders')
    ->aggregate('AVG', 'total');

echo 'Average order value: $' . number_format($avgOrderValue, 2);

Best Practices

1. Use Parameterized Queries - QueryBuilder handles parameter binding automatically
2. Chain Methods - Leverage fluent interface for readable code
3. Test SQL Output - Use toSql() to verify generated queries
4. Use Indexes - Ensure frequently queried columns are indexed
5. Limit Results - Always use limit() for large datasets
6. Use Aggregates - Let database do counting/summing instead of PHP
7. Escape Output - Always escape displayed data with htmlspecialchars()
8. Index Performance - Monitor slow queries and optimize accordingly

Related Documentation

• XoopsDatabase - Database layer and connections
• Criteria - Legacy Criteria-based query system
• ../Core/XoopsObject - Data object persistence
• ../Module/Module-System - Module database operations

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See also: XOOPS Database API