indexing - When the non-clustered index is created on SQL Server -


Do I run an index creation command? When the data in the table is removed, is the index created after rejoining the index?

When you issue a CREATE INDEX command, the index is created

And the index is maintained , e.g. By entering and removing data, the "fly" index will auto-update - no special reproduction is required.

This is the reason that a table of too many indices can negatively affect your performance - for each insert, update or delete all the entries which are present on the table They have to be maintained - and this takes a little bit of time for each index.

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