Informix - Problembeschreibung
| Problem IT10384 | Status: Geschlossen | 
WITH AN LBAC PROTECTED TABLE SPL WHERE CLAUSE USING VARIABLE PARAMETER WILL TAKE SEQUENTIAL SCAN  | |
| Produkt: | |
INFORMIX SERVER / 5725A3900 / C10 - IDS 12.10  | |
| Problembeschreibung: | |
In SPL, a query like this, on an LBAC protected table, will 
yield an index access as expected: 
 
 select col2 into ret from my_tab where col1=10000; 
 
  1) informix.lbac_tab: INDEX PATH 
 
        Filters: LBACEnforceRow(informix.lbac_tab.lbl ) 
 
    (1) Index Name: andreasl.idx_lbac_tab_col1 
        Index Keys: col1   (Serial, fragments: ALL) 
        Lower Index Filter: informix.lbac_tab.col1 = 10000 
 
 
whereas the same query using a variable parameter instead of 
literal would take a sequential scan path: 
 
 let l_id = 10000; 
 select col2 into ret from my_tab where col1=l_id; 
 
  1) informix.lbac_tab: SEQUENTIAL SCAN  (Serial, fragments: 
ALL) 
 
        Filters: (LBACEnforceRow(informix.lbac_tab.lbl ) AND 
informix.lbac_tab.col1 = '<VAR>' ) 
 
 
Even when forcing index access, this index would be read 
sequentially: 
 
 let l_id = 10000; 
 select {+INDEX(lbac_tab idx_lbac_tab_id)} col2 into ret from 
my_tab where col1=l_id; 
 
 
  1) informix.lbac_tab: INDEX PATH 
 
        Filters: (LBACEnforceRow(informix.lbac_tab.lbl ) AND 
informix.lbac_tab.col1 = '<VAR>' ) 
 
    (1) Index Name: andreasl.idx_lbac_tab_col1 
        Index Keys: col1   (Serial, fragments: ALL) 
 
 
Explicitely updating statistics, or re-creating the index, would 
even make the second SPL (parametrized statement) fail with: 
 
  768: Internal error in routine lbac_chk_idx_fltrs: unsafe 
filter in index scan. | |
| Problem-Zusammenfassung: | |
**************************************************************** * USERS AFFECTED: * * All users * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Update to IBM Informix Server 12.10.xC6 * ****************************************************************  | |
| Local-Fix: | |
| Lösung | |
Problem Fixed In IBM Informix Server 12.10.xC6  | |
| Workaround | |
keiner bekannt / siehe Local-Fix  | |
| Weitere Daten | |
Datum - Problem gemeldet : Datum - Problem geschlossen : Datum - der letzten Änderung:  | 28.07.2015 30.12.2015 30.12.2015  | 
| Problem behoben ab folgender Versionen (IBM BugInfos) | |
12.10.xC6  | |
| Problem behoben lt. FixList in der Version | |
| 12.10.xC6 | 
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