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...
data2(id, val) as (select 1, null from dual union all select 2, '2' from dual).
Select Language English Afrikaans Albanian Arabic Armenian Azerbaijani Basque Belarusian Bulgarian Catalan Chinese (Simplified) Chinese (Traditional) Croatian Czech Danish Dutch Estonian Filipino Finnish French Galician Georgian German Greek Haitian...
qndbq9bbxilymanual') union all select version(),null,null,null,null#qjqgq.
select, is obvious. null, is just a place holder that is used because a union statement requires that the number of fields match the 1st query
SELECT * FROM schedule WHERE IS NOT NULL.
99 or 1=1 union select null, concat(table_name,0x0a,column_name) from information_ schema.columns - since where clause cannot be
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).
The IS NOT NULL operator is used to test for non-empty values (NOT NULL values). The following SQL lists all customers with a value in the "Address" field
SELECT header, txt FROM news UNION ALL SELECT name, pass FROM members This will combine results from both news table and members table and return all of them. Another Example: ' UNION SELECT 1, 'anotheruser', 'doesnt matter', 1--. UNION – Fixing Language Issues.