Strange problem with inserts.

Hi,

I'm usign PostgreSQL v7.1.2 under Solaris 7  + DBD::Pg for a project
degree. The project is about data adquisiction and process. In the last
days when a lot of data (10>-->20 rec/sec. is inserted the processes
that are reading gets records that not correspond with the statement
that are executing.

p.e:
 The process 'A' reads data with type = A
    SELECT * FROM data_collected where type = A order by id.

id is indexed.
Looking the logs the process 'A' process data with type 'B' or 'C' or
'D' and of course "A".

Any Idea?

                            Thanks.