Clustered index scan and clustered index seek

Source: Internet
Author: User
Tags sql server query

In the Execution Plan of SQL Server Query analyzer, there are many scanning methods, including clustered index scan and clustered index seek. What are the differences between the two?

Clustered index, which is a clustered index, indicates that all of them use clustered index scanning.

Scan indicates that it scans a range or all content, and seek indicates scanning rows within a specific range. In other words, scan does not know what the target row is, and seek scan indicates that I already know what the target row is, so seek is generally faster.

Which of the following statements is scan and which is seek scan?

Use master
Select * From sysobjects
Select * From sysobjects where name like 'sys %'
Select * From sysobjects where ID <3

Because the sysobjects table is a clustered index on the ID, scan is used for the first two query statements, and seek is used for the last two query statements.

Tered index scan and clustered index seek icons

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