The permitted range of query re-execution differs between the server mode and the data source mode. The permitted range is as follows:

• In the server mode
  Query execution
  
• In the data source mode
  From timestamp adjustment to query execution
  

For details about the timestamp adjustment function, see 10.8 Timestamp adjustment for tuples.

You use a tuple log file that has been acquired to re-execute a query. A query can be re-executed in an environment that is different from the environment used to acquire the tuple logs, except that the default character encoding must be the same in both environments.

This example assumes that the environment in which queries are re-executed is different from the environment where tuple logs were acquired.

To re-execute queries:

1. Copy the required files to the environment where queries are to be re-executed.
   Copy the query definition files for the query group to be re-executed, query group property file, and tuple log file from the environment where tuples were acquired to the environment where the queries are to be re-executed.
   
2. Specify the settings required for acquiring tuple logs.
   Specify BUFFER in the tpl.outputTrigger parameter in the query group property file to acquire tuple logs from the output stream queue. If you use a tuple log file acquired in the server mode, specify true in the stream.tupleLogMode parameter.
   
3. Register the query group to be re-executed.
   Use the sdpcql command to register the query group to be re-executed.
   
4. Start the query group to be re-executed.
   Use the sdpcqlstart command to start the query group to be re-executed.
   
5. Re-execute the queries.
   Use the sdptplput command to reload tuples from the tuple log file and then re-execute the queries.
   
6. Check the results.
   Use the sdptplls command to display the contents of the tuple log file in the output stream queue and check the results.
   

For details about the sdpcql, sdpcqlstart, sdptplput, and sdptplls commands, see sdpcql (registers a query group), sdpcqlstart (starts a query group), sdptplput (reloads tuples), and sdptplls (displays tuple information) in 7. Commands.

• If you re-execute queries by loading tuples starting with any tuple other than the first tuple loaded by an adaptor, the results might differ from those obtained when the queries were executed using the adaptor.
• Because the sdptplput command does not reproduce the tuple loading interval, the input stream queue might result in an overflow. If overflow occurs, the operation depends on whether the server mode or the data source mode is used:
  
  • In the server mode
    A tuple whose reload failed is reloaded at the interval specified in the -interval option. In this case, the KFSP42005-E and KFSP52003-E messages are displayed, but they have no effect on query re-execution.
    
  • In data source mode
    If queue overflow occurs, the query group is shut down, resulting in a query re-execution error. Therefore, use the -interval and -count options to adjust the interval at which tuples are reloaded and the number of tuples to be reloaded.
    
• Do not start adaptors while the sdptplput command is executing. If adaptors are started at such a time, the following occurs:
  
  • When input adaptors are started
    The reloaded tuples are intermixed with the tuple loaded by the input adaptors, thereby causing the results obtained from query re-execution to be different from the results obtained when queries were executed by using the input adaptors.
    
  • When output adaptors are started
    Overflow might occur in the output stream queue, resulting in shutdown of the query group.