|
Problem IT36682
|
Status: Closed |
QUERY WITH INDEX SCAN ON A COLUMNAR TABLE WHICH IS UNDER A UNIONMAY GET INCORRECT RESULT
|
| product: |
DB2 FOR LUW / DB2FORLUW / B50 - DB2 |
| Problem description: |
QUERY WITH INDEX SCAN ON A COLUMNAR TABLE WHICH IS UNDER A UNION
MAY GET INCORRECT RESULT.
Union leg with the CDE index fetch needs to be more complex -
for example, have NLJN between CDE index scan and Union.
Example of the plan:
Plan Graph:
Rows
Operator
(ID)
Cost
2
RETURN
( 1)
12.0948
|
2
SCAN
( 2)
12.0948
|
2
SORT
( 3)
12.0133
|
2
UNION
( 4)
11.8146
/
1 1
NLJN *SCAN*
( 5) ( 9)
11.8098 0.0048
/ |
1 1 TFunc:
FETCH *SCAN* SYSIBM
( 6) ( 8) GENROW
2.60333 9.20648
/ |
1 1 1
ISCAN Columnar Table: Table:
( 7) Schema ELENA
0.20428 Table_CDE Table_ROW
|
1
Index:
Schema
Index_name |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* BLU *
****************************************************************
* PROBLEM DESCRIPTION: *
* See Error Description *
****************************************************************
* RECOMMENDATION: *
* Upgrade to 11.5 FP7 or later *
**************************************************************** |
| Local Fix: |
db2set DB2_REDUCED_OPTIMIZATION="COL_IXSCAN_ALL_V1133 OFF"
-im option can be used, BUT Static sql will need to be rebound
and already compiled dynamic sql re-compiled as well. |
| Solution |
|
| Workaround |
****************************************************************
* USERS AFFECTED: *
* BLU *
****************************************************************
* PROBLEM DESCRIPTION: *
* See Error Description *
****************************************************************
* RECOMMENDATION: *
* Upgrade to 11.5 FP7 or later *
**************************************************************** |
| Comment |
Upgrade to 11.5 FP7 or later |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 23.04.2021
22.11.2021
09.12.2021 |
| Problem solved at the following versions (IBM BugInfos) |
|
| Problem solved according to the fixlist(s) of the following version(s) |
