function Update::__toString

Implements PHP magic __toString method to convert the query to a string.

Return value

string The prepared statement.

Overrides Query::__toString

File

core/lib/Drupal/Core/Database/Query/Update.php, line 166

Class

Update

General class for an abstracted UPDATE operation.

Namespace

Code

public function __toString() {
    if (!is_array($this->fields) || !is_array($this->arguments) || !is_array($this->expressionFields)) {
        throw new \UnexpectedValueException();
    }
    // Create a sanitized comment string to prepend to the query.
    $comments = $this->connection
        ->makeComment($this->comments);
    // Expressions take priority over literal fields, so we process those first
    // and remove any literal fields that conflict.
    $fields = $this->fields;
    $update_fields = [];
    foreach ($this->expressionFields as $field => $data) {
        if ($data['expression'] instanceof SelectInterface) {
            // Compile and cast expression subquery to a string.
            $data['expression']->compile($this->connection, $this);
            $data['expression'] = ' (' . $data['expression'] . ')';
        }
        $update_fields[] = $this->connection
            ->escapeField($field) . '=' . $data['expression'];
        unset($fields[$field]);
    }
    $max_placeholder = 0;
    foreach ($fields as $field => $value) {
        $update_fields[] = $this->connection
            ->escapeField($field) . '=:db_update_placeholder_' . $max_placeholder++;
    }
    $query = $comments . 'UPDATE {' . $this->connection
        ->escapeTable($this->table) . '} SET ' . implode(', ', $update_fields);
    if (count($this->condition)) {
        $this->condition
            ->compile($this->connection, $this);
        // There is an implicit string cast on $this->condition.
        $query .= "\nWHERE " . $this->condition;
    }
    return $query;
}