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Originally published at Internet.comIf you run a query and accidentally make a mistake by entering a table that does not exist in the database, what happens? SQL Server returns an error message. Actually, SQL Server reacts to all errors in the same manner, whether those errors are generated by users, databases, objects, or the system. SQL Server returns a formatted error message and/or writes the error message to the error log and/or event log. Here is a quick example that executes a SQL statement to update a nonexistence table in the pubs database. The SQL statement for the example is as follows: UPDATE new_authors Set author1 = "Spenik", author2 = "Sledge", title="Microsoft SQL Server DBA Survival Guide"
When the statement is executed, the following error message is returned: Server: Msg 208, Level 16, State 1, Line 1 Invalid object name 'new_authors'. The preceding error message demonstrates the standard message format for error messages returned by SQL Server.
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The first thing presented in the error message is the message number, severity level, state, and line number. To most users, these numbers are just garbage to be ignored, so they skip down to the message and try to resolve the problem. In reality, the error message number is very useful for obtaining more error information. You can use the severity levels to help find errors that need to be handled. When tracking a problem, always write down all the error information, including the message number, severity level, and state. In many cases, these will be of more assistance than the actual message...
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