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Can we replicate non-clustered index to subscribers?
Replicating Non-Clustered Indexes Improves Subscriber Query Performance. One of the advantages of replication is that subscribing servers can be used for reporting thereby offloading RO query activity from the Publisher. Find the Copy Nonclustered Indexes setting, set this option to true, and click OK.
Are indexes replicated?
CREATE INDEX and ALTER INDEX are not replicated, so if you add or change an index at, for example, the Publisher, you must make the same addition or change at the Subscriber if you want it reflected there.
How is non-clustered index stored?
When a table has a clustered index, the table is called a clustered table. If a table has no clustered index, its data rows are stored in an unordered structure called a heap.
How are nonclustered indexes replicated in SQL Server?
Indexes are key to the performance of SQL Server, but only clustered key indexes are replicated by default. Unique constraints are replicated by default, so their indexes will also be created on subscribers, but nonclustered indexes are not replicated by default.
Why do we need non clustered indexes in SQL Server?
Additional subscriber non-clustered indexes don’t come without a cost. Like all SQL Server indexes, there is additional overhead for INSERT, UPDATE, DELETE, additional locks\\blocking, and index maintenance to consider. Add only the non-clustered indexes supporting the business needs of the Subscriber.
Why are unique constraints not replicated by default?
Unique constraints are replicated by default, so their indexes will also be created on subscribers, but nonclustered indexes are not replicated by default. While setting up transaction replication on a database, we can change the default settings for articles on the Articles window to include nonclustered indexes.
What are the advantages and disadvantages of replication?
One of the advantages of replication is that subscribing servers can be used for reporting thereby offloading RO query activity from the Publisher. Recently I worked on a performance case on such a replication subscriber, which would have been prevented with a simple change to the article properties for this publication.