<?php
/**
* Part of the Joomla Framework Database Package
*
* @copyright Copyright (C) 2005 - 2021 Open Source Matters, Inc. All rights reserved.
* @license GNU General Public License version 2 or later; see LICENSE
*/
namespace Joomla\Database\Query;
/**
* Trait for MySQL Query Building.
*
* @since 2.0.0
*/
trait MysqlQueryBuilder
{
/**
* Magic function to convert the query to a string.
*
* @return string The completed query.
*
* @since 2.0.0
*/
public function __toString()
{
switch ($this->type) {
case 'select':
if ($this->selectRowNumber) {
$orderBy = $this->selectRowNumber['orderBy'];
$tmpOffset = $this->offset;
$tmpLimit = $this->limit;
$this->offset = 0;
$this->limit = 0;
$tmpOrder = $this->order;
$this->order = null;
$query = parent::__toString();
$this->order = $tmpOrder;
$this->offset = $tmpOffset;
$this->limit = $tmpLimit;
// Add support for second order by, offset and limit
$query = PHP_EOL . 'SELECT * FROM (' . $query . PHP_EOL . "ORDER BY $orderBy" . PHP_EOL . ') w';
if ($this->order) {
$query .= (string) $this->order;
}
return $this->processLimit($query, $this->limit, $this->offset);
}
}
return parent::__toString();
}
/**
* Method to modify a query already in string format with the needed additions to make the query limited to a particular number of
* results, or start at a particular offset.
*
* @param string $query The query in string format
* @param integer $limit The limit for the result set
* @param integer $offset The offset for the result set
*
* @return string
*
* @since 2.0.0
*/
public function processLimit($query, $limit, $offset = 0)
{
if ($limit > 0 && $offset > 0) {
$query .= ' LIMIT ' . $offset . ', ' . $limit;
} elseif ($limit > 0) {
$query .= ' LIMIT ' . $limit;
}
return $query;
}
/**
* Concatenates an array of column names or values.
*
* @param string[] $values An array of values to concatenate.
* @param string|null $separator As separator to place between each value.
*
* @return string The concatenated values.
*
* @since 2.0.0
*/
public function concatenate($values, $separator = null)
{
if ($separator !== null) {
$statement = 'CONCAT_WS(' . $this->quote($separator);
foreach ($values as $value) {
$statement .= ', ' . $value;
}
return $statement . ')';
}
return 'CONCAT(' . implode(',', $values) . ')';
}
/**
* Aggregate function to get input values concatenated into a string, separated by delimiter
*
* Usage:
* $query->groupConcat('id', ',');
*
* @param string $expression The expression to apply concatenation to, this may be a column name or complex SQL statement.
* @param string $separator The delimiter of each concatenated value
*
* @return string Input values concatenated into a string, separated by delimiter
*
* @since 2.0.0
*/
public function groupConcat($expression, $separator = ',')
{
return 'GROUP_CONCAT(' . $expression . ' SEPARATOR ' . $this->quote($separator) . ')';
}
/**
* Method to quote and optionally escape a string to database requirements for insertion into the database.
*
* This method is provided for use where the query object is passed to a function for modification.
* If you have direct access to the database object, it is recommended you use the quote method directly.
*
* Note that 'q' is an alias for this method as it is in DatabaseDriver.
*
* Usage:
* $query->quote('fulltext');
* $query->q('fulltext');
* $query->q(array('option', 'fulltext'));
*
* @param array|string $text A string or an array of strings to quote.
* @param boolean $escape True (default) to escape the string, false to leave it unchanged.
*
* @return string The quoted input string.
*
* @since 2.0.0
* @throws \RuntimeException if the internal db property is not a valid object.
*/
abstract public function quote($text, $escape = true);
/**
* Get the regular expression operator
*
* Usage:
* $query->where('field ' . $query->regexp($search));
*
* @param string $value The regex pattern.
*
* @return string
*
* @since 2.0.0
*/
public function regexp($value)
{
return ' REGEXP ' . $value;
}
/**
* Get the function to return a random floating-point value
*
* Usage:
* $query->rand();
*
* @return string
*
* @since 2.0.0
*/
public function rand()
{
return ' RAND() ';
}
/**
* Find a value in a varchar used like a set.
*
* Ensure that the value is an integer before passing to the method.
*
* Usage:
* $query->findInSet((int) $parent->id, 'a.assigned_cat_ids')
*
* @param string $value The value to search for.
* @param string $set The set of values.
*
* @return string A representation of the MySQL find_in_set() function for the driver.
*
* @since 2.0.0
*/
public function findInSet($value, $set)
{
return ' find_in_set(' . $value . ', ' . $set . ')';
}
/**
* Return the number of the current row.
*
* Usage:
* $query->select('id');
* $query->selectRowNumber('ordering,publish_up DESC', 'new_ordering');
* $query->from('#__content');
*
* @param string $orderBy An expression of ordering for window function.
* @param string $orderColumnAlias An alias for new ordering column.
*
* @return $this
*
* @since 2.0.0
* @throws \RuntimeException
*
* @todo Remove this method when the database version requirements have been raised
* to >= 8.0.0 for MySQL and >= 10.2.0 for MariaDB so the ROW_NUMBER() window
* function can be used in any case.
*/
public function selectRowNumber($orderBy, $orderColumnAlias)
{
// Use parent method with ROW_NUMBER() window function on MariaDB >= 10.2.0 and MySQL >= 8.0.0.
if (version_compare($this->db->getVersion(), $this->db->isMariaDb() ? '10.2.0' : '8.0.0', '>=')) {
return parent::selectRowNumber($orderBy, $orderColumnAlias);
}
$this->validateRowNumber($orderBy, $orderColumnAlias);
return $this->select("(SELECT @rownum := @rownum + 1 FROM (SELECT @rownum := 0) AS r) AS $orderColumnAlias");
}
/**
* Casts a value to a char.
*
* Ensure that the value is properly quoted before passing to the method.
*
* Usage:
* $query->select($query->castAs('CHAR', 'a'));
*
* @param string $type The type of string to cast as.
* @param string $value The value to cast as a char.
* @param string $length The value to cast as a char.
*
* @return string SQL statement to cast the value as a char type.
*
* @since 1.0
*/
public function castAs(string $type, string $value, ?string $length = null)
{
switch (strtoupper($type)) {
case 'CHAR':
if (!$length) {
return $value;
} else {
return 'CAST(' . $value . ' AS CHAR(' . $length . '))';
}
// No break
case 'INT':
return '(' . $value . ' + 0)';
}
return parent::castAs($type, $value, $length);
}
}