function SelectQuery::addField

Overrides SelectQueryInterface::addField

File

includes/database/select.inc, line 1319

Class

SelectQuery

Query builder for SELECT statements.

Code

public function addField($table_alias, $field, $alias = NULL) {
    // If no alias is specified, first try the field name itself.
    if (empty($alias)) {
        $alias = $field;
    }
    // If that's already in use, try the table name and field name.
    if (!empty($this->fields[$alias])) {
        $alias = $table_alias . '_' . $field;
    }
    // If that is already used, just add a counter until we find an unused alias.
    $alias_candidate = $alias;
    $count = 2;
    while (!empty($this->fields[$alias_candidate])) {
        $alias_candidate = $alias . '_' . $count++;
    }
    $alias = $alias_candidate;
    $this->fields[$alias] = array(
        'field' => $field,
        'table' => $table_alias,
        'alias' => $alias,
    );
    return $alias;
}