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 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
select a,b,null,null from table1 union select null,null,c,d from table2 union select null,null,null,null,e,f from table3.
[Amber] Carole and Tuesday - 17 [1080p].mp4 added 2 min. ago. 553 MB. [Mokusei Zaijuu] Zetsubou Inaka Shojo A Virgin’s Netorare Rape and Despair ~Aomori Hen~ EXTENDED [English].zip added 12 min. ago.
union all select null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null
A field with a NULL value is a field with no value. If a field in a table is optional, it is possible to insert a new record or update a record without adding a value to this
i am trying to do union i get data with null values and i want do not want it to show in result. such as: column1 col2 col3 col4 col5 col6 test1 1 2 3 null 6 test2 2 3 4 null 6 test3 3 4 5 6 null
In general, every NULL value is taken into account to vary from each alternative NULL in the database.
Обработка значений NULLHandling Null Values. 03/30/2017. Время чтения: 7 мин. В этой статье. Значение NULL в реляционной базе данных
NULL в Системах управления базами данных (СУБД) — специальное значение (псевдозначение), которое может быть записано в поле таблицы базы данных (БД). NULL соответствует понятию «пустое поле», то есть «поле, не содержащее никакого значения».