@Override
public ResultSet executeQuery(String sql) throws SQLException {
checkClosed();
beforeExecute();
long begin = System.currentTimeMillis();
// Create a temp table for querying ResultSet and ensure its creation.
// If the table can not be created (CANCELLED/FAIL), an exception will be caused.
// Once the table has been created, it will last until the Statement is closed,
// or another query is started.
String tempTempTable = "jdbc_temp_tbl_" + UUID.randomUUID().toString().replaceAll("-", "_");
try {
executeInstance =
runClientSQL(
"create table "
+ tempTempTable
+ " lifecycle "
+ connHanlde.lifecycle
+ " as "
+ sql);
boolean complete = false;
while (!complete) {
try {
Thread.sleep(POOLING_INTERVAL);
} catch (InterruptedException e) {
break;
}
Instance.TaskStatus.Status status;
try {
status = executeInstance.getTaskStatus().get("SQL").getStatus();
} catch (NullPointerException e) {
continue;
}
switch (status) {
case SUCCESS:
complete = true;
break;
case FAILED:
String reason = executeInstance.getTaskResults().get("SQL");
connHanlde.log.fine("create temp table failed: " + reason);
throw new SQLException("create temp table failed: " + reason, "FAILED");
case CANCELLED:
connHanlde.log.info("create temp table cancelled");
throw new SQLException("create temp table cancelled", "CANCELLED");
case WAITING:
case RUNNING:
case SUSPENDED:
break;
}
}
} catch (OdpsException e) {
connHanlde.log.fine("create temp table failed: " + e.getMessage());
throw new SQLException(e);
}
// If we arrive here, the temp table must be effective
tempTable = tempTempTable;
long end = System.currentTimeMillis();
connHanlde.log.fine("It took me " + (end - begin) + " ms to create " + tempTable);
// Read schema
begin = System.currentTimeMillis();
List<String> columnNames = new ArrayList<String>();
List<OdpsType> columnSqlTypes = new ArrayList<OdpsType>();
try {
Table table = connHanlde.getOdps().tables().get(tempTable);
table.reload();
for (Column col : table.getSchema().getColumns()) {
columnNames.add(col.getName());
columnSqlTypes.add(col.getType());
}
} catch (OdpsException e) {
throw new SQLException(e);
}
OdpsResultSetMetaData meta = new OdpsResultSetMetaData(columnNames, columnSqlTypes);
end = System.currentTimeMillis();
connHanlde.log.fine("It took me " + (end - begin) + " ms to read the table schema");
// Create a download session through tunnel
DownloadSession session;
try {
TableTunnel tunnel = new TableTunnel(connHanlde.getOdps());
String project_name = connHanlde.getOdps().getDefaultProject();
session = tunnel.createDownloadSession(project_name, tempTable);
connHanlde.log.info("create download session id=" + session.getId());
} catch (TunnelException e) {
throw new SQLException(e);
}
resultSet =
isResultSetScrollable
? new OdpsScollResultSet(this, meta, session)
: new OdpsForwardResultSet(this, meta, session);
return resultSet;
}