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
Note: A NULL value is different from a zero value or a field that contains spaces.
select cast (2000 as type of quint) from rdb$database select cast (2000 as int) from rdb$database. If TYPE OF is used with a (VAR)CHAR type, its character.
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...
Best Result For : 999999.9 uNiOn aLl sElEcT cAsT 0x393133353134353632312e39 as char --. تفسير فرط السبحة في المنام.
11223344) UNION SELECT NULL,NULL,NULL,NULL WHERE 1=2 –- Если нет ошибки, значит синтаксис верный, т.е. используется MS SQL Server.
...Null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,concat
It should be noted that NULL pointer is different from an uninitialized and dangling pointer.
NULL - это дефайн, который указывает на участок памяти, в котором гарантировано не лежат никакие данные. Сейчас это уже пережиток С, с появлением С++11 для таким целей нужно использовать nullptr. Fatmarmelad, в вашем примере "NULL"...