SQL "select where not in subquery" returns no results
Sep 10, 2009 · The long answer (From T-SQL Fundamentals, Third edition, by Itzik Ben-Gan) This is an example: Imagine there is a order with a NULL orderid inside Sales.Orders table, so …
sql - How to use MAX () on a subquery result? - Stack Overflow
Apr 24, 2013 · Here, an aggregate may not appear in the WHERE clause unless it is in a subquery contained in a HAVING clause or a select list, and the column being aggregated is …
SQL LEFT JOIN Subquery Alias - Stack Overflow
Dec 19, 2016 · As for the joined subquery, it requires retrieving all rows matching the meta_key value from the wp_postmeta table before joining on post/order id's. So it should be safe to …
sql - Difference between WITH clause and subquery? - Stack …
May 6, 2015 · The WITH clause is for subquery factoring, also known as common table expressions or CTEs: The WITH query_name clause lets you assign a name to a subquery …
sql - What is the difference between LATERAL JOIN and a …
Things a subquery can't do There are things that a LATERAL join can do, but a (correlated) subquery cannot (easily). A correlated subquery can only return a single value, not multiple …
sql - NOT IN vs NOT EXISTS - Stack Overflow
The subquery inside the NOT IN statement can be evaluated at the beginning of the execution, and the temporary table can be checked against each value in the outer select, rather than re …
using if else in sql server subquery - Stack Overflow
I'm not sure why the following subquery doesn't work in SQL Server, when I run the subquery by itself it works just fine, but as soon as I add Select * from ([subquery]) as table1 the query …
Getting an average from subquery values or another aggregate …
Sep 8, 2009 · Getting an average from subquery values or another aggregate function in SQL Server Asked 16 years, 2 months ago Modified 7 years, 1 month ago Viewed 78k times
sql - Is there a performance difference between CTE , Sub-Query ...
Jun 23, 2012 · SQL is a declarative language, not a procedural language. That is, you construct a SQL statement to describe the results that you want. You are not telling the SQL engine how …
sql - Where clause on subquery statement in select - Stack Overflow
A subquery like this one you have should return only an scalar value. Secondly, the subquery can have only one column in its column list, so again the return value should be a scalar one. At …