What is logical and physical join in sql server

Question

What is logical and physical join in sql server.

geetha geetha · Answer

Logical Joins: Logical joins are simple joins we apply on sql queries.logical joins are, Inner join Outer join Left outer Right Outer join Full outer join Physical joins: User did'nt write the sql query for physical join, instead of we implement in sql server engine or operators or algorithms. Here i attached the example of logical join.

Jaimin Shethiya · Answer

Hello Dilshad, Can you please check the below brief description for logical and physical join in sql. 1. Logical Joins: These joins are simple joins that we apply in our SQL queries, like INNER JOIN, RIGHT/LEFT OUTER JOIN, CROSS JOIN, OUTER APPLY, etc. 2. Physical Joins: These are the joins that users don’t use/write in their SQL queries. Instead these are implemented inside SQL Server engine as operators or algorithms to implement the Logical Joins. Their types are Nested Loop, Merge and Hash. Thanks

Jignesh Kumar · Answer

Hi Silshad Ali, Please refer this blog where its explained well which may help you, https://www.c-sharpcorner.com/blogs/physical-join-vs-logical-join-in-sql-server

Rajanikant Hawaldar · Answer

Physical joins are the ones, which will be used by sql Server internally. You will not write queries with them unless you explicitly specify with Hints. Logical joins: Inner join, Outer join, Full join, Cross join, Apply operators Physical Joins: Merge join, Hash join

Mageshwaran R · Answer

Hi, Please refer the below link, it might helps you https://sqlwithmanoj.com/2010/10/06/physical-join-vs-logical-join/

Harsh Shah · Answer

Hi Dilshad, please refer below answer. Logical join: Inner Join, Left outer join, Cross Join, Outer apply. This joins are written by user. Physical joins: Nested loop, merge join and hash join is common operators which we will see in execution plan as long as query contains any logical joins (inner join, outer join, cross join, semi join). These three joins are called Physical joins. Hope this will help you. Thank you.

Sonu Gupta · Answer

Hi, Visit the following URL- https://sqlwithmanoj.com/2010/10/06/physical-join-vs-logical-join/

What is logical and physical join in sql server

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