Index Seek vs Index Scan in SQL Server -


please explain difference between index scan , index seek in ms sql server sample example, since helpful know, what's real use of it. in advance.

here text showplan (slightly edited brevity) query using scan:

|–table scan(object:([orders]), where:([orderkey]=(2)))

the following figure illustrates scan:

enter image description here

here text showplan same query using seek:

 |–index seek(object:([orders].[okey_idx]), seek:([orderkey]=(2)) ordered forward)

enter image description here

have on sql server plans : difference between index scan / index seek


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