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Problem IT17264
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Status: Closed |
SELECT FIRST N WITH ORDER BY RETURNS THE WRONG NUMBER OF ROWS IFTHE QUERY PLAN USES INDEX-SELF JOIN
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| product: |
INFORMIX SERVER / 5725A3900 / C10 - IDS 12.10 |
| Problem description: |
A SELECT FIRST N query with ORDER BY will return either 0 or the
wrong number of rows if the query plan uses index-self join on
index fragmented by range. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* Users of 12.10.xC1 through 12.10.xC7. *
****************************************************************
* PROBLEM DESCRIPTION: *
* A query may produce incorrect results under the following *
* conditions: *
* - Query on a single table, with an order by clause with *
* descending order on a column that leads an index (ascending *
* order on lead key) *
* - the index is a composite index with at least two index *
* keys *
* - the first index key column has a small number of *
* distinct values, and update statistics medium or high has *
* been run on the leading key column *
* - there exists a predicate on the 2nd index key column *
* which selects a small fraction of the table *
* - index self-join is being used to access the table, with *
* the index being traversed in reverse order *
****************************************************************
* RECOMMENDATION: *
* Update to IBM Informix Server 12.10.xC8 *
**************************************************************** |
| Local Fix: |
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| Solution |
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| Workaround |
not known / see Local fix |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 28.09.2016
09.12.2016
09.12.2016 |
| Problem solved at the following versions (IBM BugInfos) |
12.10.xC8
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| Problem solved according to the fixlist(s) of the following version(s) |
