Submitting a Teradata SQL Request - Call-Level Interface Version 2

Submitting a Teradata SQL Request

A Teradata SQL request must be submitted to Teradata Database for processing by using the Initiate Request function. To initiate a request after a session is established, an application must perform the following steps:

1 Modify the DBCAREA.

a Set the Function to Initiate Request.

b Set the Input CLIv2 Session Id to the Output CLIv2 Session Id obtained when the session was established.

c Set the Request Pointer.

d Set the Request Length.

e Optionally set the following:

Positioning‑action

Positioning‑statement‑number

Positioning‑value

Request Buffer Length

Request‑parcel‑format

Response Buffer Length

Anticipated Number of Concurrent Sessions

Request‑token

Using Data Pointer

Using Data Length

Using‑data‑count

Using‑data‑length‑vector

Using‑data‑pointer‑vector

Data‑encryption

Message Area Pointer

Message Area Length

Any option values required (remember to set Change Options = Y if any option values are changed)

2 Call DBCHCL to perform the Initiate Request function.

3 Check the return code from DBCHCL:

Return Code	Results
0	Call DBCHCL to perform a Fetch function (see “Fetching the Response for a Request” on page 58) until the complete response has been processed.
anything else	Process the return code and DBCAREA message.

4 Call DBCHCL to perform the End Request function. See “Ending a Request” on page 61.

The Teradata SQL request might require input data. In this situation, an application must pass the address and length of the data area to CLI. The Using Data Pointer and Using Data Length fields of the DBCAREA are provided for this purpose.