|Subject||Re: [firebird-support] firebird and transaction behaviour questions|
one select do not guarantee consistency if you run something outside of transaction context.
And because of this, in Firebird there is no possibility to do this.
consider folowing example
inner join detail d on d.id_h=h.id
server do loop throught streams and:
1. it got header 1 (ver1)
2. it got details for header 1 (ver1)
3. it got header 2.(ver1)
4. other client update header 2(store ver2) and details for header 2(store ver2).
5. it got details for header 2(ver2)
as you can see you got inconsistent view in point 5 –
because you got header 2 ver 1 but details from ver2 –
but you should got header 2 ver 1 and detail for header 2 ver 1
because of that streams and all other table code work in transaction contexts.
Ah. thank you for clarifying this. I always try to do select for a report in
one select statement with joints etc. In the scenario you described below -
yes, we need a transaction.