The following table lists the use of three most common CLIv2 routines and describes how they are used.
| Routine | Description | |||
|---|---|---|---|---|
| DBCHINI | What | Initializes the application allocated DBCAREA. | ||
| Why | Prepares for interaction with CLIv2. | |||
| DBCHCL | What | Manages interaction with the Teradata Database; each type of interaction is called a function. | ||
| Why | Sends/receives Teradata SQL requests/responses to/from the Teradata Database. The following table lists the functions associated with the DBCHCL routine. | |||
| Function Name | What it Represents | Use | ||
| CON | Connect | Logs a session on to the Teradata Database and specifies a set of services | ||
| RSUP | RunStartUp | Submits a request to execute the startup request stored on the Teradata Database | ||
| IRQ | Initiate Request | Submits a Teradata SQL request from the application | ||
| IWPF | Initiate With Protocol-Function | Submits a Teradata SQL request from the application and allows Teradata Database Two-phase commit protocol sync point performance optimization | ||
| CRQ | Continue Request | Provides data requested by the Teradata Database to complete an SQL request | ||
| CMD | Command | Issues a TDP command within a CLIv2 program | ||
| ABT | Abort | Aborts a request asynchronously | ||
| FET | Fetch | Makes available the next parcel or buffer (which one depends on the setting of Parcel Mode) of the Teradata SQL response | ||
| REW | Rewind | Repositions to start of Teradata SQL response (spool file) | ||
| ERQ | End Request | Closes a Teradata SQL request and has the Teradata Database discard the response | ||
| DSC | Disconnect | Logs off and deletes a session | ||
| DBCHCLN | What | Logs off all sessions and releases the internal CLIv2 memory areas allocated by DBCHINI | ||
| Why | To clean up after interacting with the Teradata Database | |||