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.
Note: A NULL value is different from a zero value or a field that contains spaces. A field with a NULL value is one that has been left blank during record creation!
The Background I was trying to solve the fourth realistic mission in hackthissite.org, and couldn't figure out exactly what SQL I should inject into the URL to retrieve the list of emails.
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...
Суть проблемы заключается в возвращении загадочного пользователя null null а именно сообщение от этого пользователя датированное 1 января 1970 годом. В следствие чего возникает ошибка, препятствующая дальнейшей работе приложения.
Thus even though you have casted null to match ssn's datatype bigint, you must give it an alias as shown below. Select*from(select driverid, name, ssn from drivers where driverid<15. UNION ALL. Select driverid,name, cast(nullas bigint) as ssn from drivers where driverid BETWEEN 18 AND 21) T.
NULL is special in SQL. NULL indicates that the data is unknown, inapplicable or even does not exist.
T-SQL SET Concat_null_yields_null. Checks whether concatenation results are treated as null or empty string values.
399 подписчиков, 1,562 подписок, 4,139 публикаций — посмотрите в Instagram фото и видео null (@null_null).
SSL_null_with_null_null. No overview available. SDKs.