Details
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Improvement
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Status: Closed
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Major
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Resolution: Won't Fix
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Description
I current version, Kylin build a snapshot table for a segment and isolate with each other in the same cube, even though some segments share the same snapshot table storage .
I some scene， we need global snapshot table for one cube, such as we has a cube with snapshot table,ID is PK，the first day, the table look like:
id name
1 A
2 B
3 C
the query 'select name, count(1) from fact join dimension group by name' get result:
A xx
B xx
C xx
the next day(segment), lookup table modified, it looks like :
id name
1 A
2 D
3 E
the same query return :
A xx
B xx
C xx
D xx
E xx
However B and D, C and E has the same ID, we need the newest result. so a global snapshot table shared by all segments which has always the newest values is needed.