How to select empty result set in SQL?

How to select empty result set in SQL?

SELECT CASE WHEN (SELECT 1 WHERE (1=0)) = 0 THEN 1 ELSE 0 END Also returns 0. So the empty result set is not 1 and not 0, it’s NULL as evidenced by SELECT CASE WHEN (SELECT 1 WHERE (1=0)) is NULL THEN 1 ELSE 0 END

How to make a query return an empty row?

1) run the query and put results in a temp table (or table variable) 2) check to see if the temp table has results 3) if not, return an empty row by performing a select statement similar to this (in SQL Server): Where columnA, columnB and columnC are your actual column names.

Is the empty result set equal to 0?

No, The query didn’t return 0 because the empty result is considered equal to 0 but because the empty result set is considered NULL and null isn’t equal to anything. Also returns 0. which returns 1. See this dbfiddle with that code.

What to do if there is no result in query?

Solution is really simple WITHOUT double select: by the “WITH TIES” you get ALL rows (all have a 1 as “orderdummy”, so all are ties), or if there is no result, you get your defaultrow. Very few options I’m afraid. You always have to touch the table twice, whether COUNT, EXISTS before, EXISTs in UNION, TOP clause etc

When to return null when result is empty?

If your select returns one value, that value is returned. If your select statement returns one column, but no rows, NULL will be returned. If your select statement returns multiple columns and/or multiple rows, this won’t work and the query fails. It’s a built in ‘fake’ table that has one record.

What happens if result set has more than one row?

Your comparison will break if your result set has more than one row or column. Msg 116 Level 16 State 1 Line 2 Only one expression can be specified in the select list when the subquery is not introduced with EXISTS. Msg 512 Level 16 State 1 Line 1 Subquery returned more than 1 value.

Why does SQL Server say null is unknown?

NULL is unknown so SQL Server doesn’t know what it’s equal to. If you rely on the existence of a result set, I agree EXISTS is probably the way to go. That’s what the construction is made for. Your comparison will break if your result set has more than one row or column.

How to check if query returns any rows without a result?

– Mark ByersMay 21 ’10 at 19:42 it is not clear if you want a result set returned and then check if any rows were int it, or if you just want to check if a query returns any rows without a result set?? – KM. May 21 ’10 at 19:53

How to store the result of dynamic SQL?

Here is the script which declares additional parameter which is Name and returns value into it. FROM [AdventureWorks2014]. [HumanResources]. [Department] You can use this script and example as a template for your need where you want to run dynamic SQL and store the result of it into a variable.

How to return dynamic results in ASP.NET MVC?

Where TypeBuilder is described in details in the post I have attached. Adding to Petr Voborník’s answer, dynamic query, I add dynamic insert of ResultSet, my application takes the dynamic query of all tables of the entire database, a chunk at a time and then inserts the dynamic results into a remote database, using Always Encrypted (omitted here).