1' UNION SELECT @--+ #The used SELECT statements have a different number of columns 1' UNION SELECT @,@--+ #The used
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...
qndbq7bbxilyCzFA') UNION ALL SELECT NULL,NULL,NULL,CONCAT(0x716e646271,IFNULL(CAST(grantee AS CHAR),0x20),0x716a716771),NULL FROM INFORMATION_SCHEMA.USER_PRIVILEGES#qjqgq.
It should be noted that NULL pointer is different from an uninitialized and dangling pointer.
If a null pointer constant is converted to a pointer type, the resulting pointer, called a null pointer, is guaranteed to compare unequal to a pointer to any object or function.
UNION ALL SELECT NULL, *, NULL, NULL FROM email. I understand what this does and why; the hacker needs to create a query that has the same number of columns as the query it's being merged with, and shifted around the * to make sure the emails are displayed. That's not my question.
From what I see, why are you adding Part3 in the second query? I'd think you want something more like this: With CTE AS (. SELECT Pull_Date, Well_Name, Part1 AS Part, Part1_PN AS PartPN, Part1_SN AS PartSN FROM testtest UNION ALL SELECT Pull_Date, Well_Name, Part2, Part2_PN, Part2_SN...
Suppose that the "UnitsOnOrder" column is optional, and may contain NULL values.
Как и в случае с обычными переменными, указатели не инициализируются при создании. Если значение не было присвоено, то указатель по умолчанию будет указывать на любой адрес, содержимым которого...
Добрый день! Подскажите, пожалуйста, что значит "NULL", и когда он применяется ? В примере ниже , насколько я понимаю, создаётся строка, и в этой