Can sql merge statement be used in a batch (oracle 10g)?

Question

Hello,
I am trying to insert into an oracle table multiple rows of values selected from a web page. Can I use a merge statement as a preparedStatement to avoid inserting duplicate records?
Does anybody have any examples they would like to share?
Any suggestions are greatly appreciated.
Thank you,
Logan

Answer 1

I've implemented this by batch inserting into a temp table then running a merge then dropping the temp table.
public void mergeMethod() {
        final String createsql = "CREATE TABLE temp (a INTEGER, b INTEGER, c INTEGER)";
        final String insertsql = "INSERT INTO temp (a, b, c) VALUES (?,?,?)";
        final String mergesql = "MERGE INTO my_table A " +
           "USING temp B ON (A.a = B.a AND A.b = B.b) " +
           "WHEN MATCHED THEN UPDATE SET A.c = B.c " +
           "WHEN NOT MATCHED THEN INSERT (A.id, A.a, A.b, A.c) " +
           "VALUES (my_seq.Nextval,B.a,B.b,B.c)";
        final String dropsql = "DROP TABLE temp";
     Connection conn = null;
     Statement cs = null;
     Statement ms = null;
     Statement ds = null;
     PreparedStatement ps = null;
     boolean retValue = false;
     try {
          conn = getConnection();
          conn.setAutoCommit(false);
          cs = conn.createStatement();
          ms = conn.createStatement();
          ds = conn.createStatement();
          ps = conn.prepareStatement(insertsql);
          for (int i=0; i< 10; i++){
               ps.setInt(1, i);
               ps.setInt(2, i+1);
               ps.setInt(3, i+2);
               ps.addBatch();
          // create temp table
          cs.execute(createsql);
          // execute in batch
          final int updateCount[] = ps.executeBatch();
          // merge the two tables
          ms.execute(mergesql);
          // drop the temp table
          ds.execute(dropsql);
          conn.commit();
          System.out.println("Rows is updated: " + updateCount.length);
     } catch (final SQLException e) {
          if (conn != null) {
              conn.rollback();
          throw e;
     } finally {
          if (ps != null) {
              ps.close();
          if (cs != null) {
              cs.close();
          if (ms != null) {
              ms.close();
          if (ds != null) {
              ds.close();
          if (conn != null) {
              conn.close();
}