Table 11 lists the remaining routines and describes how they are used.
Routine |
Description |
|
DBCHERR
|
What: |
Fetches textual description corresponding to the CLI error code. |
Why: |
To allow application to retrieve error text from functions other than DBCHCL or DBCHINI. |
|
Where: |
All clients. |
|
DBCHFER |
What: |
Fetches textual description and error codes for the last error detected for a specific session, or the last error that occurred overall. |
Why: |
To provide adequate information about an error condition so that applications or users can recover from, or correct the condition. |
|
Where: |
All clients. |
|
DBCHPEC |
What: |
Sets the global CLI attention flag. |
Why: |
To return control to the application program when some event occurs such as a signal like a control-C break. |
|
Where: |
All clients. |
|
DBCHQE |
What: |
Queries the Teradata Database. |
Why: |
To see default information prior to logging on so that changes can be made before starting a session. |
|
Where: |
All clients. |
|
DBCHREL |
What: |
Returns the release level and version numbers of the software running on the database computer handling the specified session. Note: For increased reliability, use the QEPIDBR field of the DBCHQE routine instead of DBCHREL. See “The qepItem Field” on page 231 for more information. |
Why: |
To generate an audit trail, to aid in debugging, and so on. |
|
Where: |
All clients. |
|
DBCHSAD |
What: |
Stores specified value at specified address. |
Why: |
To return the address of a given parameter. |
|
Where: |
All clients. |
|
DBCHUE |
What: |
Associates platform-defined events with user defined contexts. |
Why: |
To associate an event with a user context in which DBCHWL waits for completion. The only event supported is a timeout event, permitting DBCHWL to return a timeout to the application in the case of no completed requests from the session list. |
|
Where: |
All Windows ™ clients. |
|
DBCHUEC |
What: |
Resets the global CLI attention flag. |
Why: |
To indicate that CLI should complete its operations before returning control to the application. |
|
Where: |
All clients. |
|
DBCHWAT |
What: |
Waits for event to occur (an “event” refers to the arrival of some response from the Teradata Database; if DBCHUEC has been invoked, “event” also refers to the occurrence of some application program-defined event). |
Why: |
To provide a mechanism for explicit waits for events and to simplify the handling of concurrent Teradata Database sessions. |
|
Where: |
All clients. |
|
DBCHWL |
What: |
Wait for completion of any active requests from a supplied session list or completion of an optionally supplied event. |
Why: |
To simplify multi-threaded applications by waiting on a specific set of sessions, events, or both. |
|
Where: |
All Windows clients. |