Sybase Adaptive Server IQ 12.4.2, Руководство по администрированию и эксплуатации

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CHAPTER 6 Using Procedures and Batches
257
Notes
• The DECLARE statement in
InnerProc
declares a symbolic name for one
of the predefined SQLSTATE values associated with error conditions
already known to the server. The DECLARE statement does not take any
other action.
• The MESSAGE statement sends a message to the server window and the
dbconsol message window.
• The SIGNAL statement generates an error condition from within the
InnerProc
procedure.
The following statement executes the
OuterProc
procedure:
CALL OuterProc();
The message window of the server then displays the following:
Hello from OuterProc.
Hello from InnerProc.
No statements following the SIGNAL statement in InnerProc are executed:
InnerProc immediately passes control back to the calling environment, which
in this case is the procedure OuterProc . No statements following the CALL
statement in OuterProc are executed. The error condition is returned to the
calling environment to be handled there. For example, DBISQL handles the
error by displaying a message window describing the error.
The TRACEBACK function provides a list of the statements that were
executing when the error occurred. You can use the TRACEBACK function
from DBISQL by typing the following statement:
SELECT TRACEBACK(*)