[TAJO-1435] Improve JDBC PreparedStatement performance

• Type: Improvement
• Status: In Progress
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 0.10.0
• Component/s: JDBC Driver
• Assignee: Unassigned
• Reporter: Dongjoon Hyun
• Created: 20/Mar/15 15:48
• Updated: 29/Feb/16 18:53

Description

After my discussing with hyunsik on https://issues.apache.org/jira/browse/TAJO-1430, I create this issue.

In this issue, Tajo PreparedStatement will be upgraded by using parsed SQL Context instead of using StringBuffer like the following.

private String updateSql(final String sql, HashMap<Integer, String> parameters) {

    StringBuffer newSql = new StringBuffer(sql);

    int paramLoc = 1;
    while (getCharIndexFromSqlByParamLocation(sql, '?', paramLoc) > 0) {
      // check the user has set the needs parameters
      if (parameters.containsKey(paramLoc)) {
        int tt = getCharIndexFromSqlByParamLocation(newSql.toString(), '?', 1);
        newSql.deleteCharAt(tt);
        newSql.insert(tt, parameters.get(paramLoc));
      }
      paramLoc++;
    }
    return newSql.toString();
  }

As a discussion, TajoCLI module has the same pattern, but TajoCLI exits immediately. So, we can not improve more at this side. If we want to improve both cases, we need to handle in deeper server side.

      if (cmd.hasOption("f")) {
        displayFormatter.setScriptMode();
        cmd.getOptionValues("");
        File sqlFile = new File(cmd.getOptionValue("f"));
        if (sqlFile.exists()) {
          String script = FileUtil.readTextFile(new File(cmd.getOptionValue("f")));
          script = replaceParam(script, cmd.getOptionValues("param"));
          int exitCode = executeScript(script);
          sout.flush();
          System.exit(exitCode);
        } else {
          System.err.println(ERROR_PREFIX + "No such a file \"" + cmd.getOptionValue("f") + "\"");
          System.exit(-1);
        }
      }

Issue Links

• is blocked by: TAJO-1437 Resolve findbug warnings on Tajo JDBC Module
• is blocked by: TAJO-1438 Resolve findbug warnings on Tajo Client Module
• is blocked by: TAJO-1512 Fix various Expr cloning bugs
• is blocked by: TAJO-1430 Improve SQLAnalyzer by session-based parsing-result caching