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Can a ColumnStore index contain a computed column?
Starting with SQL Server 2017, a clustered columnstore index can contain a non-persisted computed column. However, in SQL Server 2017, clustered columnstore indexes cannot contain persisted computed columns, and you cannot created nonclustered indexes on computed columns.
How to create clustered ColumnStore index in SQL Server?
Starting with SQL Server 2016 (13.x), you can create the table as a clustered columnstore index. It is no longer necessary to first create a rowstore table and then convert it to a clustered columnstore index. For information on index design guidelines, refer to the SQL Server Index Design Guide.
Why is the VS Code IntelliSense not working?
After updating the environment variables in registry settings, the VS code IntelliSense started working. Checking the console is a good start to find the root cause of this issue. This is because of C# extension issue. Reinstall the extension will work. Simply reinstall the extension and restart the VSCode/PC.
Can you run analytics on a nonclustered ColumnStore index?
Beginning with SQL Server 2016 (13.x), you can have a nonclustered columnstore index on a rowstore disk-based table or an in-memory OLTP table. This makes it possible to run the analytics in real-time on a transactional table. While transactions are occurring on the underlying table, you can run analytics on the columnstore index.
Do you need to index all of your columns?
No, you should not index all of your columns, and there’s several reasons for this: There is a cost to maintain each index during an insert, update or delete statement, that will cause each of those transactions to take longer. It will increase the storage required since each index takes up space on disk.
Is there an overhead in indexing all columns?
No, there is overhead in maintaining the indexes, so indexing all columns would slow down all of your insert, update and delete operations. You should index the columns that you are frequently referencing in WHERE clauses, and you will see a benefit.
Can a nonkey column be included in an index?
They can be data types not allowed as index key columns. They are not considered by the Database Engine when calculating the number of index key columns or index key size. An index with nonkey columns can significantly improve query performance when all columns in the query are included in the index either as key or nonkey columns.