Correlated subquery in sql Part 60 скачать в хорошем качестве

Correlated subquery in sql Part 60

In this video we will discuss about Corelated Subqueries In Part 59, we discussed about 2 examples that uses subqueries. Please watch Part 59, before proceeding with this video. We will be using the same tables and queries from Part 59. Healthy diet is very important both for the body and mind. If you like Aarvi Kitchen recipes, please support by sharing, subscribing and liking our YouTube channel. Hope you can help.    / @aarvikitchen5572   In the example below, sub query is executed first and only once. The sub query resutls are then used by the outer query. In a non-corelated subquery, the subquery can be executed independently of the outer query. Select [Id], [Name], [Description] from tblProducts where Id not in (Select Distinct ProductId from tblProductSales) If the subquery depends on the outer query for its values, then that sub query is called as a correlated subquery. In the where clause of the subquery below, "ProductId" column get it's value from tblProducts table that is present in the outer query. So, here the subquery is dependent on the outer query for it's value, hence this subquery is a correlated subquery. Correlated subqueries get executed, once for every row that is selected by the outer query. corelated subquery, cannot be executed independently of the outer query. Select [Name], (Select SUM(QuantitySold) from tblProductSales where ProductId = tblProducts.Id) as TotalQuantity from tblProducts order by Name Text version of the video http://csharp-video-tutorials.blogspo... Slides http://csharp-video-tutorials.blogspo... All SQL Server Text Articles http://csharp-video-tutorials.blogspo... All SQL Server Slides http://csharp-video-tutorials.blogspo... All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenka... All Dot Net and SQL Server Tutorials in Arabic    / kudvenkatarabic