public function addConnection(string $connectionName, \PDO $connection): void
    {
        $this->connections[$connectionName] = $connection;
    }
public function addConnection(string $connectionName, \PDO $connection): void
    {
        $this->connections[$connectionName] = $connection;
    }
public function addConnection ( string $ connectionName , \ PDO $ connection ) : void { $ this -> connections [ $ connectionName ] = $ connection ; }
Adds database connection to pool.

@param string $connectionName
@param \PDO $connection
@return void
Adds database connection to pool .