How do I throw an exception in PostgreSQL?

How do I throw an exception in PostgreSQL?

PostgreSQL RAISE EXCEPTION

1. RAISE: This is defined as an exception statement that was used to raise the exception in PostgreSQL.
2. LEVEL: Level in raise exception is defined as defining the error severity.
3. FORMAT: This is defined as an error message which we want to display.

How can a user-defined exception be raised?

User-defined exceptions must be raised explicitly by RAISE statements. To handle raised exceptions, you write separate routines called exception handlers. The use of OTHERS is optional and is allowed only as the last exception handler. You cannot include OTHERS in a list of exceptions following the keyword WHEN .

What is PSQL exception?

Introduction to the PL/pgSQL Exception clause When an error occurs in a block, PostgreSQL will abort the execution of the block and also the surrounding transaction. To recover from the error, you can use the exception clause in the begin… PL/pgSQL passes the control to the statement after the end keyword.

What is Sqlerrm in PL SQL?

The function SQLERRM returns the error message associated with its error-number argument. If the argument is omitted, it returns the error message associated with the current value of SQLCODE . SQLERRM with no argument is useful only in an exception handler. The message begins with the Oracle error code.

Can we raise same exception in two blocks?

You can, however, declare the same exception in two different blocks. Exceptions declared in a block are considered local to that block and global to all its sub-blocks. Because a block can reference only local or global exceptions, enclosing blocks cannot reference exceptions declared in a sub-block.

Can exception section have raise statement?

You can code a RAISE statement for a given exception anywhere within the scope of that exception. When an exception is raised, if PL/SQL cannot find a handler for it in the current block, the exception propagates to successive enclosing blocks, until a handler is found or there are no more blocks to search.

How to handle an exception in PL / pgSQL?

1 First, when an error occurs between the begin and exception, PL/pgSQL stops the execution and passes the control to the exception list. 2 Second, PL/pgSQL searches for the first condition that matches the occurring error. 3 Third, if there is a match, the corresponding handle_exception statements will execute. Weitere Artikel…

How to raise an exception in PL / SQL?

Summary: in this tutorial, you will learn how to use the PL/SQL RAISE statement to raise a user-defined exception, internally defined exception, and reraising an exception. To raise an exception explicitly, you use the RAISE statement. The RAISE statement allows you to: Raise a user-defined exception.

How to raise errors and display them in plpgsql?

EXCEPTION; ROLLBACK TRANSACTION; RAISE ERROR @ErrorMessage, @LineNumber, @ErrorState –how to catch errors and display them???? END; How to print a message like ‘PRINT’ in T-SQL? How to raise errors with exception information?

What happens when no match is found in PL / pgSQL?

PL/pgSQL passes the control to the statement after the end keyword. Finally, if no match found, the error propagates out and can be caught by the exception clause of the enclosing block. In case there is no enclosing block with the exception clause, PL/pgSQL will abort the processing.