/** * Add a not null condition to the condition array. * The order of the method call is important, in which way the condition string will * concatenate. * * @param ColumnInterface $column Name of the column to compare. * * @return $this The same instance to concatenate methods. */ public function notNull(ColumnInterface $column) { $columnName = $column->getAlias() ?: $column->getColumnName(); $condition = $columnName . ' IS NOT NULL'; $this->_addCondition($condition); return $this; }