I have following data in my table "devices" … I executed below query … It returns result given below … How to come out of this so that it should ignore NULL AND result should be …
select sum(case when a is null then 1 else 0 end) count_nulls , count(a) count_not_nulls from us; Or
I dont want to return null value, how to check not null or how to make isset cond in query …
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.
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..?
I am writing a PHP and MySQL application in which i have to concatenate multiple column values into one single column.I would have used the concat() function,but it does not handle null values...
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
SELECT * FROM members WHERE username = 'admin'--' AND password = 'password' This is
Например, SELECT 'abc' + NULL дает в результате NULL.For example, SELECT 'abc' + NULL yields NULL. Когда параметр SET CONCAT_NULL_YIELDS_NULL установлен в значение OFF, объединение значения NULL со строкой дает в результате исходную строку (значение NULL...
mysql> SELECT NULL, 1+NULL, CONCAT('Invisible',NULL); To search for column values that are NULL, you cannot use an expr = NULL test. The following statement returns no rows, because expr = NULL is never true for any expression: Press CTRL+C to copy. mysql> SELECT * FROM my_table...