PowerBuilder Help Using SQL in scripts
General information

PowerScript supports standard embedded SQL statements and dynamic SQL statements in scripts.
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Error handling in scripts

The scripts shown in the SQL examples above do not include error handling, but it is good practice to test the success and failure codes (the SQLCode attribute) in the transaction object after every statement .

Value Meaning 0 Success100 Fetched row not found-1 Error; the statement failed. Use SQLErrText or SQLDBCode to obtain the detail.
After certain statements such as DELETE, FETCH, and UPDATE, you should also check the SQLNRows property of the transaction object to make sure the action affected at least one row.
About SQLErrText and SQLDBCode The string SQLErrText in the transaction object contains the database vendor-supplied error message. The long named SQLDBCode in the transaction object contains the database vendor-supplied status code:

IF SQLCA.SQLCode = -1 THEN
MessageBox("SQL error", SQLCA.SQLErrText)
END IF