sql - Union to handle NULL values - Stack Overflow
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.
999999.9 /**/union/**/all /**/select /**/cast...
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.
sql - SELECT CASE CAST Conversion Error - Stack Overflow
I'm querying the back-end of an application. For what ever reason the developer decided to use NVARCHAR for all fields. I'm having a problem with one of the "date" fields--somehow it got populated...
sql - WHERE all IS NOT NULL - Stack Overflow | Post as a guest
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..?
coding style - SQL - Select null as FIELDNAME? - Stack Overflow
I have come across some code that says … What exactly is this doing? Is it getting the field names unitcost and markup? Why would you use "select null as..."? New to this sorry. Thanks.
NULL or BLANK fields (ORACLE) - Stack Overflow | Post as a guest
Select null, 'Actual null' from dual union all select '', 'Null string' from dual union all select ' ', 'Single space' from dual union all
sql - What is the Null Character literal in TSQL? - Stack Overflow
Note: not a NULL field value, but the null character (see link). I have a column with a mix of typical and a null character.
SQL NULL Values - IS NULL and IS NOT NULL
Note: A NULL value is different from a zero value or a field that contains spaces.
Null character - Wikipedia
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)...
Использование значения NULL в условиях поиска | Интерактивный...
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).