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.
select cast (2000 as type of quint) from rdb$database select cast (2000 as int) from rdb$database. If TYPE OF is used with a (VAR)CHAR type, its character.
select cast (2000 as type of quint) from rdb$database select cast (2000 as int) from rdb$database.
How can I run a MySQL query that selects everything that is not null? It would be something like … Do I just remove the all and go..?
Select char_length(cast('123456789 1' as varchar(10))) from rdb$database. Получаем: Exception ... string truncation Т.е. пробел мы обрезать можем, а другие символы нет. Так и должно быть или нет?
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...
The null character (also null terminator or null byte), abbreviated NUL or NULL, is a control character with the value zero.
You can use the Oracle IS NOT NULL condition in either a SQL statement or in a block of PLSQL code.
Null values can arise when you refer to message fields that do not exist, access database columns for which no data has been supplied, or use the keyword NULL
Note: A NULL value is different from a zero value or a field that contains spaces.