[DERBY-25] INSERT INTO SELECT DISTINCT ... skips some values for autoincrement column

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Duplicate
• Affects Version/s: 10.0.2.0
• Component/s: SQL
• Assignee: Unassigned
• Reporter: Tulika Agrawal
• Created: 30/Sep/04 20:23
• Updated: 05/Jun/05 05:44
• Resolved: 05/May/05 07:35

Description

Reporting for Mamta Satoor.

If we use insert into desttable, select
distinct from source, into a desttable which has autoincrement
column in it, we might see gaps in the autoincrement column if
there are duplicated rows in the source table. The reason for
this is Derby projects values into destination table columns before
building a distinct resultset from the source table. The piece
of code doing this is in org.apache.derby.impl.sql.execute.ProjectRestrictResultSet class's getNextRowCore() method where it calls doProjection.