Difference
between Filtered Index and Indexed View
Filtered indexes have the following
advantages over indexed views-
Criteria
|
Filtered Index
|
Indexed Views
|
Maintenance Costs
|
Reduced index maintenance costs because the query processor uses
fewer CPU resources to update a filtered index
|
The query processor uses more CPU resources to update a Indexed
View.
|
Plan Quality
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Improved plan quality because during query compilation, the
query optimizer considers using a filtered index in more situations
|
They are not so benificial in the query optimizer as Filtered
Index
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Online index rebuilds
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A Filtered indexes while they are available for queries
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Online index rebuilds are not supported for indexed views
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Non-unique indexes
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Filtered indexes can be non-unique
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Indexed views must be unique
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Only One Table
|
A Filtered Index is created on column(s) of a particular
table.
|
Index Views can be created on column(s) from multiple base
tables.
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Simple WHERE criteria
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A Filtered Index can not use complex logic in its WHERE clause,
for example the LIKE clause, NOT IN, OR and dynamic / non-deterministic
predicates like WHERE col >= DATEADD(DAY, -1, GETDATE()) are not allowed,
only simple comparison operators are allowed.
|
This limitation does not apply to indexed views and you can
design your criteria as complex as you want.
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