What is MERGE in SQL Server with example?

What is MERGE in SQL Server with example?

Runs insert, update, or delete operations on a target table from the results of a join with a source table. For example, synchronize two tables by inserting, updating, or deleting rows in one table based on differences found in the other table. MERGE is currently in preview for Azure Synapse Analytics.

How do you write a MERGE statement in SQL?

First, you specify the target table and the source table in the MERGE clause. Second, the merge_condition determines how the rows from the source table are matched to the rows from the target table. It is similar to the join condition in the join clause.

What is the purpose of MERGE in SQL Server 2008?

Starting with SQL Server 2008, you can use a MERGE statement to modify data in a target table based on data in a source table. The statement joins the target to the source by using a column common to both tables, such as a primary key.

How do I MERGE two datasets in SQL?

Different Types of SQL JOINs

  1. (INNER) JOIN : Returns records that have matching values in both tables.
  2. LEFT (OUTER) JOIN : Returns all records from the left table, and the matched records from the right table.
  3. RIGHT (OUTER) JOIN : Returns all records from the right table, and the matched records from the left table.

How do I MERGE rows in SQL Server?

You can concatenate rows into single string using COALESCE method. This COALESCE method can be used in SQL Server version 2008 and higher. All you have to do is, declare a varchar variable and inside the coalesce, concat the variable with comma and the column, then assign the COALESCE to the variable.

How do I join 3 columns in SQL?

Joining 3 Tables Using a Junction Table

  1. The first step is to look at the schema and select the columns we want to show.
  2. The next step is to determine which tables will be necessary for the query.
  3. In the final part, we’ll have to join all the tables together.

How do I merge 4 tables in SQL?

Joining 4 Tables in SQL

  1. Introduction :
  2. Step-1: Create a database –
  3. Step-2: Use the database –
  4. Step-3: Creating table1 –
  5. Step-4: Creating table2 –
  6. Step-5: Creating table3 –
  7. Step-6: Creating table4 –