sysmessages -- > SYSUSERMESSAGES

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If format-string is not supplied or is empty, the error number is used to locate an error message in the system tables. Adaptive Server Enterprise obtains messages 17000-19999 from the SYSMESSAGES table. In Adaptive Server Anywhere this table is an empty view, so errors in this range should provide a format string. Messages for error numbers of 20000 or greater are obtained from the SYS.SYSUSERMESSAGES table

Описание выполнения получается ERROR[ sqlstate | sqlcode ]

где
The SQLSTATE value is set after each statement. You can check the SQLSTATE to see whether or not the statement succeeded
и
The SQLCODE value is set after each statement. You can check the SQLCODE to see whether or not the statement succeeded