sql injection "union select null" - CodeProject | To display as
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...
c - Is (int *) 0 a null pointer? - Stack Overflow
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.
c++ - Is uninitialized char* a null pointer? - Stack Overflow
An uninitialized pointer can be null or non-null (or "both" or "neither"), and relying on predictable behaviour when using it is a bad idea. – chris May 9 '15 at 4:22. @chris, but if I use "string* s" then it always prints an andress like "0x401dee" – lxdthriller May 9 '15 at 4:26. @lxdthriller, And it doesn't...
Шпаргалка по SQL инъекциям | DefconRU
Используйте NULL в UNION-инъекциях вместо попыток угадать строку, дату, число и прочее. Но будьте аккуратны при слепой инъекции, т.к. вы можете спутать ошибку БД и самого приложения. Некоторые языки, например ASP.NET, выдают ошибку при использовании значения NULL (т.к...
Нулевые указатели (null и nullptr) в C++ | Уроки С++ - Ravesli
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...
Confusing SQL error in SELECT NULL, *, NULL, NULL - Stack Overflow
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.
sql - WHERE all IS NOT NULL - Stack Overflow
SELECT * FROM schedule WHERE ((all)) IS NOT NULL. Do I just remove the all and go..?
NULL pointer in C - GeeksforGeeks
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.”
sql - MySQL SELECT only not null values - Stack Overflow
You should use IS NOT NULL. (The comparison operators = and <> both give UNKNOWN with NULL on either side of the expression.)
Заметка про NULL / Хабр | select col from ttt where col is not null
Соответственно, IS NOT NULL действует наоборот: вернёт истину, если значение операнда отлично от NULLа и ложь, если он является NULLом