SELECT SUBSTR( NVL2(column01, ','||column01, '') || NVL2(column02, ','||column02, '') || NVL2(column03, ','||column03, '') || NVL2(column04, ','||column04, '') || NVL2(column05, ','||column05, '') || NVL2(column06, ','||column06, '') || NVL2(column07, ','||column07, '') || NVL2(column08, ','||column08, '') || NVL2(column09, ','||column09, '') , 2) columns FROM t ;