protected function _createNullTerm( $name )
	{
		switch( $this->getOperator() )
		{
			case '==':
				return $name . ' === null';
			case '!=':
				return $name . ' !== null';
			default:
				throw new MW_Common_Exception( sprintf( 'null value not allowed for operator "%1$s"', $this->getOperator() ) );
		}
	}
protected function _createNullTerm( $name )
	{
		switch( $this->getOperator() )
		{
			case '==':
				return $name . ' === null';
			case '!=':
				return $name . ' !== null';
			default:
				throw new MW_Common_Exception( sprintf( 'null value not allowed for operator "%1$s"', $this->getOperator() ) );
		}
	}
protected function _createNullTerm ( $ name ) { switch ( $ this -> getOperator ( ) ) { case '==' : return $ name . ' === null' ; case '!=' : return $ name . ' !== null' ; default : throw new MW_Common_Exception ( sprintf ( 'null value not allowed for operator "%1$s"' , $ this -> getOperator ( ) ) ) ; } }
Creates a term which contains a null value.

@param string $name Translated name of the variable or column
@return string Created term string (name operator null)
Creates a term which contains a null value .