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 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...
Перевод отдельных слов, фраз, а также целых текстов и веб-страниц (английский, немецкий, французский, испанский, польский и др.).
Best Result For : 999999.9 uNiOn aLl sElEcT cAsT 0x393133353134353632312e39 as char --. تفسير فرط السبحة في المنام.
Синтаксис: 0xHEX_ЧИСЛО (SM): SELECT CHAR(0x66) (S) SELECT 0x5045 (это не число, а строка) (M) SELECT 0x50 + 0x45
If field is not sanitized, and only if the number of the columns used in the UNION SELECT match with the columns of the query, most likely will appear the string 91351456272.9 somewhere in the page. That will be the confirmed for the attacker of a vulnerability in the page.
...NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,concat
Coming to our discussion, NULL macro is defined as ((void *)0) in header files of most of the C compiler implementations. But C standard is saying that 0 is also a null pointer constant.
Соответственно, IS NOT NULL действует наоборот: вернёт истину, если значение операнда отлично от NULLа и ложь, если он является NULLом