I read in a book (Thinking in Java by Bruce Eckel, 4th edition, page 47) that null is equal to '\u000'. And then I was wondering what exactly does '\u000' really mean.
11223344) UNION SELECT NULL,NULL,NULL,NULL WHERE 1=2 –- Если нет ошибки, значит синтаксис верный, т.е. используется MS SQL Server.
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 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 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?
The null character (also null terminator or null byte), abbreviated NUL or NULL, is a control character with the value zero. It is present in many character sets, including ISO/IEC 646 (or ASCII)...
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
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».
This special treatment of NULL is why, in the previous section, it was necessary to determine which animals are no longer alive using death IS NOT NULL instead of death <> NULL. Two NULL values are regarded as equal in a GROUP BY. When doing an ORDER BY, NULL values are presented first if...