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  1. Derby
  2. DERBY-822

Client driver: Pre-fetch data on executeQuery()

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    Details

    • Type: Improvement
    • Status: Closed
    • Priority: Minor
    • Resolution: Fixed
    • Affects Version/s: 10.2.1.6
    • Fix Version/s: 10.2.1.6
    • Component/s: Network Server
    • Labels:
      None
    • Issue & fix info:
      Release Note Needed
    • Bug behavior facts:
      Performance

      Description

      Currently, the client driver does not pre-fetch data when
      executeQuery() is called, but it does on the first call to
      ResultSet.next(). Pre-fetching data on executeQuery() would reduce
      network traffic and improve performance.

      The DRDA protocol supports this. From the description of OPNQRY (open
      query):

      The qryrowset parameter specifies whether a rowset of rows is to be
      returned with the command. This is only honored for non-dynamic
      scrollable cursors (QRYATTSNS not equal to QRYSNSDYN) and for
      non-scrollable cursors conforming to the limited block query
      protocol. The target server fetches no more than the requested
      number of rows. It may fetch fewer rows if it is restricted by extra
      query block limits, or if a fetch operation results in a negative
      SQLSTATE or an SQLSTATE of 02000.

        Attachments

        1. DERBY-822-v1.diff
          813 kB
          Knut Anders Hatlen
        2. DERBY-822-v1.stat
          1 kB
          Knut Anders Hatlen
        3. DERBY-822-v2.diff
          12 kB
          Knut Anders Hatlen
        4. DERBY-822-v2.stat
          0.5 kB
          Knut Anders Hatlen
        5. DERBY-822-v3.diff
          10 kB
          Knut Anders Hatlen
        6. DERBY-822-v3.stat
          0.5 kB
          Knut Anders Hatlen

          Activity

            People

            • Assignee:
              knutanders Knut Anders Hatlen
              Reporter:
              knutanders Knut Anders Hatlen
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              Dates

              • Created:
                Updated:
                Resolved: