DB2 - Problembeschreibung
| Problem IT07803 | Status: Geschlossen |
QUERIES WITH CASE WHEN USING SUBQUERIES MAY LEAD TO PERFORMANCE ISSUE. | |
| Produkt: | |
DB2 FOR LUW / DB2FORLUW / A10 - DB2 | |
| Problembeschreibung: | |
Queries in the following form may show bad performance when a
CASE WHEN condition contains subqueries:
SELECT COUNT(*)
FROM
(SELECT T1.COL1, T1.COL2, T1.COL3, T1.COL4,
T1.COL5, T1.COL6, T1.COL7, T1.COL8
FROM TAB01 T1 INNER JOIN TAB02 T2 INNER JOIN session.#tt4 T3
ON 1=1 ON (T1.COL2 = T2.COL2)
WHERE ((T2.COL6 = 'My string' AS CHAR(16)FOR BIT DATA))) AND
CASE
WHEN (T3.COL55 > CAST(2 AS NUMERIC(1, 0)))
THEN CAST(x'01' AS CHAR(1) FOR BIT DATA)
ELSE
CASE
WHEN (((T2.MyCol_A IN (SELECT T4.MyCol_B AS MyCol_B FROM
session.#tt5 T4))
OR (T2.MyCol_C IN (SELECT T5.MyCol_B AS MyCol_B FROM
session.#tt5 T5)))
OR (T2.MyCol_D IN (SELECT T6.MyCol_B AS MyCol_B FROM
session.#tt5 T6)))
THEN CAST(x'01' AS CHAR(1) FOR BIT DATA)
ELSE CAST(x'00' AS CHAR(1) FOR BIT DATA)
END
END = CAST(x'01' AS CHAR(1) FOR BIT DATA)) | |
| Problem-Zusammenfassung: | |
**************************************************************** * USERS AFFECTED: * * all * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to version 10.1 Fix Pack 5 * **************************************************************** | |
| Local-Fix: | |
| Lösung | |
First fixed in version 10.1 Fix Pack 5 | |
| Workaround | |
keiner bekannt / siehe Local-Fix | |
| Weitere Daten | |
Datum - Problem gemeldet : Datum - Problem geschlossen : Datum - der letzten Änderung: | 19.03.2015 16.07.2015 16.07.2015 |
| Problem behoben ab folgender Versionen (IBM BugInfos) | |
| Problem behoben lt. FixList in der Version | |
| 10.1.0.5 |
|