SELECT m.id, m.name, m.description, m.directions, COUNT(j.markerid) as marker_jingles FROM markers AS m LEFT OUTER JOIN jingles AS j ON j.markerid=m.id WHERE 1. But am a bit stuck because I cannot figure out how to get it to return rows when the COUNT is 0.
So the expressions ISNULL(NULL, 1) and COALESCE(NULL, 1) although equivalent have different nullability values. This makes a difference if you are using these expressions in computed columns, creating key constraints or making the return value of a scalar UDF deterministic so that it can be...
SELECT * FROM `mydata`.`mytable` WHERE CONCAT(<list of columns>) IS NOT 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...
Also, if null values are a possibility in your primary key, then you may want to re-evaluate your data model. Again, I know the OP's question is about querying where data is not null. But as I mentioned before, Cassandra CQL doesn't have a NOT or != operator, so that's going to be a problem right there.
SELECT val1 AS val FROM your_table WHERE val1 IS NOT NULL UNION ALL SELECT val2 FROM your_table
SELECT * FROM book WHERE author = 'null'
IF EXISTS (SELECT * FROM dbo.table1 WHERE school = 'xxxxxxxxxxxxx'). SELECT COUNT(*) AS thecount.
Синтаксис: 0xHEX_ЧИСЛО (SM): SELECT CHAR(0x66) (S) SELECT 0x5045 (это не число, �� строка) (M) SELECT 0x50 + 0x45 (теперь это число) (M)
Существуют специальные операторы IS NULL и IS NOT NULL, которые позволяют производить сравнения с NULLами.