class DatabaseCondition in Drupal 7
Generic class for a series of conditions in a query.
Hierarchy
- class \DatabaseCondition implements \Countable, QueryConditionInterface
Expanded class hierarchy of DatabaseCondition
Related topics
File
- includes/
database/ query.inc, line 1652 - Non-specific Database query code. Used by all engines.
View source
class DatabaseCondition implements QueryConditionInterface, Countable {
/**
* Array of conditions.
*
* @var array
*/
protected $conditions = array();
/**
* Array of arguments.
*
* @var array
*/
protected $arguments = array();
/**
* Whether the conditions have been changed.
*
* TRUE if the condition has been changed since the last compile.
* FALSE if the condition has been compiled and not changed.
*
* @var bool
*/
protected $changed = TRUE;
/**
* The identifier of the query placeholder this condition has been compiled against.
*/
protected $queryPlaceholderIdentifier;
/**
* Constructs a DataBaseCondition object.
*
* @param string $conjunction
* The operator to use to combine conditions: 'AND' or 'OR'.
*/
public function __construct($conjunction) {
$this->conditions['#conjunction'] = $conjunction;
}
/**
* Implements Countable::count().
*
* Returns the size of this conditional. The size of the conditional is the
* size of its conditional array minus one, because one element is the
* conjunction.
*/
public function count() {
return count($this->conditions) - 1;
}
/**
* Implements QueryConditionInterface::condition().
*/
public function condition($field, $value = NULL, $operator = NULL) {
if (!isset($operator)) {
if (is_array($value)) {
$operator = 'IN';
}
elseif (!isset($value)) {
$operator = 'IS NULL';
}
else {
$operator = '=';
}
}
$this->conditions[] = array(
'field' => $field,
'value' => $value,
'operator' => $operator,
);
$this->changed = TRUE;
return $this;
}
/**
* Implements QueryConditionInterface::where().
*/
public function where($snippet, $args = array()) {
$this->conditions[] = array(
'field' => $snippet,
'value' => $args,
'operator' => NULL,
);
$this->changed = TRUE;
return $this;
}
/**
* Implements QueryConditionInterface::isNull().
*/
public function isNull($field) {
return $this
->condition($field);
}
/**
* Implements QueryConditionInterface::isNotNull().
*/
public function isNotNull($field) {
return $this
->condition($field, NULL, 'IS NOT NULL');
}
/**
* Implements QueryConditionInterface::exists().
*/
public function exists(SelectQueryInterface $select) {
return $this
->condition('', $select, 'EXISTS');
}
/**
* Implements QueryConditionInterface::notExists().
*/
public function notExists(SelectQueryInterface $select) {
return $this
->condition('', $select, 'NOT EXISTS');
}
/**
* Implements QueryConditionInterface::conditions().
*/
public function &conditions() {
return $this->conditions;
}
/**
* Implements QueryConditionInterface::arguments().
*/
public function arguments() {
// If the caller forgot to call compile() first, refuse to run.
if ($this->changed) {
return NULL;
}
return $this->arguments;
}
/**
* Implements QueryConditionInterface::compile().
*/
public function compile(DatabaseConnection $connection, QueryPlaceholderInterface $queryPlaceholder) {
// Re-compile if this condition changed or if we are compiled against a
// different query placeholder object.
if ($this->changed || isset($this->queryPlaceholderIdentifier) && $this->queryPlaceholderIdentifier != $queryPlaceholder
->uniqueIdentifier()) {
$this->queryPlaceholderIdentifier = $queryPlaceholder
->uniqueIdentifier();
$condition_fragments = array();
$arguments = array();
$conditions = $this->conditions;
$conjunction = $conditions['#conjunction'];
unset($conditions['#conjunction']);
foreach ($conditions as $condition) {
if (empty($condition['operator'])) {
// This condition is a literal string, so let it through as is.
$condition_fragments[] = ' (' . $condition['field'] . ') ';
$arguments += $condition['value'];
}
else {
// It's a structured condition, so parse it out accordingly.
// Note that $condition['field'] will only be an object for a dependent
// DatabaseCondition object, not for a dependent subquery.
if ($condition['field'] instanceof QueryConditionInterface) {
// Compile the sub-condition recursively and add it to the list.
$condition['field']
->compile($connection, $queryPlaceholder);
$condition_fragments[] = '(' . (string) $condition['field'] . ')';
$arguments += $condition['field']
->arguments();
}
else {
// For simplicity, we treat all operators as the same data structure.
// In the typical degenerate case, this won't get changed.
$operator_defaults = array(
'prefix' => '',
'postfix' => '',
'delimiter' => '',
'operator' => $condition['operator'],
'use_value' => TRUE,
);
$operator = $connection
->mapConditionOperator($condition['operator']);
if (!isset($operator)) {
$operator = $this
->mapConditionOperator($condition['operator']);
}
$operator += $operator_defaults;
$placeholders = array();
if ($condition['value'] instanceof SelectQueryInterface) {
$condition['value']
->compile($connection, $queryPlaceholder);
$placeholders[] = (string) $condition['value'];
$arguments += $condition['value']
->arguments();
// Subqueries are the actual value of the operator, we don't
// need to add another below.
$operator['use_value'] = FALSE;
}
elseif (!$operator['delimiter']) {
$condition['value'] = array(
$condition['value'],
);
}
if ($operator['use_value']) {
foreach ($condition['value'] as $value) {
$placeholder = ':db_condition_placeholder_' . $queryPlaceholder
->nextPlaceholder();
$arguments[$placeholder] = $value;
$placeholders[] = $placeholder;
}
}
$condition_fragments[] = ' (' . $connection
->escapeField($condition['field']) . ' ' . $operator['operator'] . ' ' . $operator['prefix'] . implode($operator['delimiter'], $placeholders) . $operator['postfix'] . ') ';
}
}
}
$this->changed = FALSE;
$this->stringVersion = implode($conjunction, $condition_fragments);
$this->arguments = $arguments;
}
}
/**
* Implements QueryConditionInterface::compiled().
*/
public function compiled() {
return !$this->changed;
}
/**
* Implements PHP magic __toString method to convert the conditions to string.
*
* @return string
* A string version of the conditions.
*/
public function __toString() {
// If the caller forgot to call compile() first, refuse to run.
if ($this->changed) {
return NULL;
}
return $this->stringVersion;
}
/**
* PHP magic __clone() method.
*
* Only copies fields that implement QueryConditionInterface. Also sets
* $this->changed to TRUE.
*/
function __clone() {
$this->changed = TRUE;
foreach ($this->conditions as $key => $condition) {
if ($key !== '#conjunction') {
if ($condition['field'] instanceof QueryConditionInterface) {
$this->conditions[$key]['field'] = clone $condition['field'];
}
if ($condition['value'] instanceof SelectQueryInterface) {
$this->conditions[$key]['value'] = clone $condition['value'];
}
}
}
}
/**
* Gets any special processing requirements for the condition operator.
*
* Some condition types require special processing, such as IN, because
* the value data they pass in is not a simple value. This is a simple
* overridable lookup function.
*
* @param $operator
* The condition operator, such as "IN", "BETWEEN", etc. Case-sensitive.
*
* @return
* The extra handling directives for the specified operator, or NULL.
*/
protected function mapConditionOperator($operator) {
// $specials does not use drupal_static as its value never changes.
static $specials = array(
'BETWEEN' => array(
'delimiter' => ' AND ',
),
'IN' => array(
'delimiter' => ', ',
'prefix' => ' (',
'postfix' => ')',
),
'NOT IN' => array(
'delimiter' => ', ',
'prefix' => ' (',
'postfix' => ')',
),
'EXISTS' => array(
'prefix' => ' (',
'postfix' => ')',
),
'NOT EXISTS' => array(
'prefix' => ' (',
'postfix' => ')',
),
'IS NULL' => array(
'use_value' => FALSE,
),
'IS NOT NULL' => array(
'use_value' => FALSE,
),
// Use backslash for escaping wildcard characters.
'LIKE' => array(
'postfix' => " ESCAPE '\\\\'",
),
'NOT LIKE' => array(
'postfix' => " ESCAPE '\\\\'",
),
// These ones are here for performance reasons.
'=' => array(),
'<' => array(),
'>' => array(),
'>=' => array(),
'<=' => array(),
);
if (isset($specials[$operator])) {
$return = $specials[$operator];
}
else {
// We need to upper case because PHP index matches are case sensitive but
// do not need the more expensive drupal_strtoupper because SQL statements are ASCII.
$operator = strtoupper($operator);
$return = isset($specials[$operator]) ? $specials[$operator] : array();
}
$return += array(
'operator' => $operator,
);
return $return;
}
}