When a client sends a SQL select language request, a typical mainframe server application (short transaction) performs the tasks in Table 1-3.
Task |
Function |
|---|---|
1. Prepare for incoming requests. Initialize the Gateway-Library environment. Specify the type of IMS TM transaction (used with IMS TM transactions only). |
TDINIT TDSETPT |
2. Accept the incoming request. Accept the incoming request. |
TDACCEPT |
3. Handle incoming SQL statements. Determine the length (in bytes) of the incoming SQL string. Retrieve the SQL string (Loop until all parameters are retrieved). |
TDSQLLEN TDRCVSQL |
4. Process the request. Retrieve the requested data from the database. |
|
5. Prepare to return results to the client. Set the length and address of each return parameter (Loop until all parameters are described). Describe each column in a row to be returned (Loop until all columns are retrieved). |
TDSETPRM TDESCRIB |
6. Return data to the client. Send data to the client, one row at a time (Loop until all rows are sent). Send the return parameters, tell the client when results are finished, and close the connection. |
TDSNDROW |
7. End the conversation. Free the TDPROC structure. Free the MVS storage (required with IMS TM; optional but recommended with CICS). |
TDFREE TDTERM |
