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 …
1)>(select count(*),concat( (select users.password) ,0x3a,floor(rand()*2)) x from (select 1 union select 2 union select 3)a group by x
...Null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,concat
CONCAT() returns NULL if any argument is NULL. Press CTRL+C to copy.
If I have this - tadd is the Address table: … Is there a way to exclude the apt_number if it doesn't exist? I was thinking of: … But it will return only those rows with apt_number...
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...
1 UNION ALL SELECT NULL,concat(0x28,column1,0x3a,column2,0x29) FROM database2.table1--. Error Based.
SELECT column_names FROM table_name WHERE column_name IS NOT NULL; Demo Database.
Существуют специальные операторы IS NULL и IS NOT NULL, которые позволяют производить сравнения с NULLами.