Re: isolation level RR

} Date: Tue, 11 Nov 1997 16:52:58 +0100 } From: Martina Lang <martina.lang@mch.sni.de> } Reply-to: martina.lang@mch.sni.de } Organization: SNI Munich } To: Katarina.Hamzova@swh.sk } Subject: Re: isolation level RR } Katarina Hamzova wrote: } > } > } > My question : } > How does isolation level repeatable read work } > I thought it places share locks on every row } > selected in queries in transaction - } > i did this: } > begin work; } > set isolation to repeatable read } > select * from table where ... } > ... } > i expected it places locks } > on rows according to where clause. } > But it placed share lock on table . } > Am i missing something ? } > } > Informix On line 7.20 DSA - SNI } > Informix On line 7.22 WGS - Win NT } > databases created in non Ansi mode } > unbuffered logging } > } > thanks } > katarina } Hi! } } If you use repeatable read, every row that is "touched" gets an shared } lock. That means, if you use select *, every row of the table is locked, } because every row is "touched" to find out if this row matches the where that was the problem - optimizer decided to use sequential scan thanks a lot for your help katarina -- Katarina Hamzova Voice : +42 7 5384324 SWH s.r.o Bratislava Slovakia Internet : Katarina.Hamzova@swh.sk