What is a “Scalar” Query?

问题:

I am using LLBLGEN where there is a method to execute a query as a scalar query. Googling gives me a definition for scalar sub-query, are they the same ?

回答1:

A scalar query is a query that returns one row consisting of one column.

回答2:

For what it's worth:

Scalar subqueries or scalar queries are queries that return exactly one column and one or zero records.

Source

回答3:

A scalar method is used for aggregate functions such as max, min, sum, avg and so on. Whenever you want to return a single value after execute the query.