Performance of jdbc insert statements and select nextval

i found the following problem:

10000 inserts with pgadmin tool into one table (primary key bigserial) can
be done wihtin 3 seconds. If i perform the same job with jdbc this takes
13 seconds. The insert statement is prepared only once, the statement for
fetching the nextval also. If i omit the select nextval execution time
improves to 8 seconds. Can anybody tell me why jdbc is 3 to four times
slower than pgadmin? I am using Postgresql 8.2 and 8.3 Database server,
java 1.5 and 1.6 and i tried the drivers 8.2 and 8.3 in type 3 and type 4.
The execution times are always identical.

thanks, Ralf
BGS Beratungsgesellschaft
Software Systemplanung AG




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