function Select::addExpression

Overrides Select::addExpression

File

core/lib/Drupal/Core/Database/Driver/pgsql/Select.php, line 117

Class

Select

PostgreSQL implementation of \Drupal\Core\Database\Query\Select.

Namespace

Code

public function addExpression($expression, $alias = NULL, $arguments = []) {
    if (empty($alias)) {
        $alias = 'expression';
    }
    // This implements counting in the same manner as the parent method.
    $alias_candidate = $alias;
    $count = 2;
    while (!empty($this->expressions[$alias_candidate])) {
        $alias_candidate = $alias . '_' . $count++;
    }
    $alias = $alias_candidate;
    $this->expressions[$alias] = [
        'expression' => $expression,
        'alias' => $this->connection
            ->escapeAlias($alias_candidate),
        'arguments' => $arguments,
    ];
    return $alias;
}