select `4` from (select 1,2,3,4,5,6 union select * from users)dbname; Injection example inside the query select author_id,title from posts where
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.
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...
SELECT * FROM table. And then I have to filter out the null values with a php loop. Is there a way to do
(M): SELECT CONCAT(login, password) FROM members. 7. Строки без кавычек Есть несколько
Итак, я сделал: select COUNT(columnname) from table WHERE ColumnName is null Который не считал нули...
Предикат IS NULL позволяет проверить отсутствие (наличие) значения в полях таблицы. Использование в этих случаях обычных предикатов сравнения может привести к неверным результатам, так как сравнение со значением NULL дает результат UNKNOWN (неизвестно).
returns non null values in group */ SELECT COUNT(Col1) FROM ##TestData; Because of this, COUNT, DISTINCT, and NULLs have a special relationship with each other
Look at the following SELECT statement: SELECT ProductName, UnitPrice * (UnitsInStock + UnitsOnOrder) FROM Products
Существуют специальные операторы IS NULL и IS NOT NULL, которые позволяют производить сравнения с NULLами.