Simple FORALL statement but runs very slow

Question

Hi Guys,
I'm new to Oracle and I start to use it with .NET application. I have to collections that I want to pass as Associative arrays to PL/SQL procedure and want to update a table based on values on those collections but it runs very very slow 10 minutes for only 1000 record.
here is the code
.NET
                OracleCommand cmd = con.CreateCommand();
                cmd.CommandText = COMMAND_TEXT;
                cmd.CommandType = CommandType.StoredProcedure;
                var memberNoParam = new OracleParameter { ParameterName = PARAM_MEMBER_NO, OracleDbType = OracleDbType.Varchar2, Value = memberNoArray, CollectionType =                                                          OracleCollectionType.PLSQLAssociativeArray };
                var statusParam = new OracleParameter { ParameterName = PARAM_STATUS, OracleDbType = OracleDbType.Int32, Value = statusArray, CollectionType =                                                          OracleCollectionType.PLSQLAssociativeArray };
                var siteIDParam = new OracleParameter { ParameterName = PARAM_SITE_ID, OracleDbType = OracleDbType.Int32, Value =                                                                                                                   GlobalizationConfigurationSettings.Current.DefaultLocale.SiteId };
                cmd.Parameters.Add(memberNoParam);
                cmd.Parameters.Add(statusParam);
                cmd.Parameters.Add(siteIDParam);                               
                cmd.ExecuteNonQuery();                      
                contextTransaction.Commit();
PL/SQL
PROCEDURE P_UPD_STATUS (
P_MEMBER_NO IN VARCHAR30_ARRAY,
P_STATUS IN INTEGER_ARRAY,
P_SITE_ID IN SITE.SITE_ID%TYPE)
IS
BEGIN
        FORALL I IN VALUES OF P_MEMBER_NO
        UPDATE DIRECT_DEBIT_MIGRATION_T
        SET
            STATUS = 1,
            STATUS_DATE = SYSDATE,
            LAST_UPD_BY = '13.10 SEPA Tool',
            LAST_UPD_DATE = SYSDATE
        WHERE SEPA_MIGRATION_ID = P_MEMBER_NO(I)
        AND SITE_ID=P_SITE_ID;   
        COMMIT;
EXCEPTION
WHEN OTHERS
THEN
DBMS_OUTPUT.PUT_LINE('PKG_ALERT ERROR: P_UPD_STATUS : ' || SQLERRM );
RAISE_APPLICATION_ERROR (-20999, SQLERRM);
END P_UPD_STATUS;
I've been reading about FORALL from yesterday with no help. please advise

Answer 1

I'm new to Oracle and I start to use it with .NET application. I have to collections that I want to pass as Associative arrays to PL/SQL procedure and want to update a table based on values on those collections but it runs very very slow 10 minutes for only 1000 record.
If your array has 1000 records than this means that you do 1000 single updates - if those updates cannot benefit from a decent index access than this will be slow as hell. So as you've been told, check indexes, statistics and the performance of a single update.
And perhaps you could rewrite your query as
        UPDATE DIRECT_DEBIT_MIGRATION_T
        SET
            STATUS = 1,
            STATUS_DATE = SYSDATE,
            LAST_UPD_BY = '13.10 SEPA Tool',
            LAST_UPD_DATE = SYSDATE
        WHERE SITE_ID=P_SITE_ID
             AND SEPA_MIGRATION_ID IN (SELECT column_value from TABLE(P_MEMBER_NO));
which would be one update processing 1000 rows rather than 1000 updates processing 1 row each.