When the value for Request-processing-option is not appropriate for the application, you should perform the following procedure before calling DBCHCL for the Connect, RunStartUp, Command, Initiate with Protocol-Function, or Initiate Request function:
- Set Change-options to ‘Y‘.
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Change Request-processing-option as follows:
If the Teradata Database is to... Then change the value for Request-processing-option to... execute the request and send back the returned data E Analyze each statement in the request. The statements may not contain parameterized SQL. If the request is valid, the Teradata Database will send back a time estimate and format information about the data that it would return if the request were executed.
Note that the time estimate is the same as EXPLAIN returns.
P Analyze each statement in the request. The statements may contain parameterized SQL. If the request is valid, the Teradata Database will return a time estimate and format information about the data that would be returned if the request were executed. The time estimate is the same as EXPLAIN returns. S Analyze each statement in the request, then execute the request. The statements may contain parameterized SQL. If the request is valid, the Teradata Database will return not only a time estimate and format information about the data returned, but also the data resulting from the executed request. Note that the time estimate is the same as EXPLAIN returns. B
The difference between "P" and "S" is that "P" does not support parameterized SQL while "S" does.
Use mnemonics for the codes. Mnemonics are provided in the language definition file for the DBCAREA.
If the request is not valid, the Teradata Database sends back an Error, StatementError, or Failure parcel, the same as if Request-processing-option is set to E.
If "S" or "B" is specified but the Teradata Database does not support that option, a Failure parcel with error code 3749 will be returned.
Request-processing-option is read by the call to DBCHCL for the Connect function and stored in the appropriate control blocks but is not used during the connect.