Thread: Fwd: [JDBC] Fwd: [ADMIN] Confuse about the behaveior of PreparedStatement.executeBatch (jdbc)

From: dmp <danap@ttc-cmc.net>

Subject: Re: [JDBC] Fwd: [ADMIN] Confuse about the behaveior of PreparedStatement.executeBatch (jdbc)

Date: December 15, 2012 12:30:50 AM GMT+08:00

To: Haifeng Liu <liuhaifeng@live.com>, pgsql-jdbc@postgresql.org

Hello,

Perhaps you should pose the question to the server mailing list. It seems that
maybe the sequence is possibly being changed in execution. In a small update,
10, the sequence stays intact, but for a larger update the server perhaps is
optimizing the sequence for execution thereby changing the order. In any case
you appeared to answer your own question.

http://archives.postgresql.org/pgsql-general/

danap.

Haifeng Liu wrote:

example code:

Connection conn = getConnection();
PreparedStatement pstmt = conn.prepareStatement("insert/update...");
for (A a : AList) {
pstmt.setParameter(...);
pstmt.addBatch();
}
pstmt.executeBatch();

I did a simple test and found that if one of the batch failed, the other update may be execute partially. when I test with 10 updates a batch, none of them are updated, when I test with 1000 updates a batch, about 700+ of them are executed, but the failed update should be the last one, which means 999 executed updates is more reasonable than 700+. But really weird thing is the getUpdateCounts method returns the reasonable information.

I don't know what happened inside this driver. Currently I have to setAutoCommit to false and use commit/rollback to achieve my goal.


On Dec 14, 2012, at 11:56 PM, dmp<danap@ttc-cmc.net>  wrote:

Hello,

Though a simple example of your code would provide a better response
from the mailing list, I will speculate based on the context of the
Java 6 API, statement class and your comments. Yes, the batch appears
to be proceeding.