Creating index on concatenated char columns fails is Postgres 9 (regression) - Mailing list pgsql-general

From Andrus
Subject Creating index on concatenated char columns fails is Postgres 9 (regression)
Date
Msg-id 147A7F6B6CF545B9925669D8584DE18D@dell2
Whole thread Raw
Responses Re: Creating index on concatenated char columns fails is Postgres 9 (regression)  (Adrian Klaver <adrian.klaver@aklaver.com>)
List pgsql-general
Steps to reproduce:
 
Run commands
 
    create temp table test (kuupaev date, kellaaeg char(5)  ) on commit drop;
    create index test on test ((kuupaev||kellaaeg));    
 
in
 
    "PostgreSQL 9.3.4, compiled by Visual C++ build 1600, 32-bit"
 
Observed result:
 
    ERROR:  functions in index expression must be marked IMMUTABLE
 
In
 
    "PostgreSQL 8.4.4, compiled by Visual C++ build 1400, 32-bit"
 
those commands work OK.
 
I need this index to speed up query
 
SELECT
    max( kuupaev||kellaaeg )
  from ALGSA
  where laonr=?nlaonr and kuupaev <=?prmLOPP and kuupaev||kellaaeg <= ?someparam
 
How to fix or other way to speed this query?
 
 
Andrus.

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