What is MERGE in SQL Server with example?

Posted on by Mary Andersen

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.

What is MERGE with example?

Merger refers to a strategic process whereby two or more companies mutually form a new single legal venture. For example, in 2015, ketchup maker H.J. Heinz Co and Kraft Foods Group Inc merged their business to become Kraft Heinz Company, a leading global food and beverage firm.

What is the purpose of MERGE in SQL Server?

The MERGE statement allows you to join a data source with a target table or view, and then perform multiple actions against the target based on the results of that join.

How to create MERGE statement with variable in SQL Server?

Stage the data in a staging table

  • Delete rows from the destination/production table that exist in the staging table
  • Insert the remaining data from the staging table into the production table

    • Is merge and merge join same in SQL Server?

    INNER JOIN: This type of join returns those rows which have matching values in both data sources

  • LEFT OUTER JOIN: This type of join returns all rows from the left-side data source with all matching rows from the right-side source
  • FULL JOIN: This type of join returns all matching rows from left and right-side data sources

    • How to debug merge in SQL Server?

    – The Debug menu and the Debug toolbar. Both the Debug menu and Debug toolbar are inactive until the focus is placed in an open Query Editor window. – The debugger keyboard shortcuts. – The Query Editor shortcut menu. – Menu items and context commands in the windows that are opened by the debugger, such as the Watch or Breakpoints windows.

    How to merge data in SQL?

    Create a clustered index on the join columns in the target table.

  • Disable other non-unique,nonclustered indexes on the target table for the duration of the bulk load MERGE,enable them afterwards.
  • Use the ORDER and UNIQUE hints in the OPENROWSET (BULK…) clause to specify how the source data file is sorted.