pl sql exception message

I have following error message.

2011-08-08 14:27:09 [E]: xxx - ORA-06502: PL/SQL: numeric or value error:
character string buffer too small
ORA-06512: at "xxx", line 1671
ORA-06512: at "xxx开发者_运维知识库", line 2083
ORA-06512: at "xxx", line 921
ORA-06512: at line 1

Can you tell me why there are many lines? It is stack unwinding or that messages were artificially put together?

It's indeed stack unwinding.

You have probably called stored procedure from a database IDE such as Toad (line 1). That procedure has a procedure call at line 921, which in turn... The error eventually occurred in a procedure or function on line 1671.

If I'm not mistaken, exception handlers can also contribute lines to the multi-line error message.