How to create procedure to mail ORA-error

Question

hi all,
anyone please tell me how to create a procedure to mail the ORA-error when ORA- error comes in alert.log

Answer 1

Ok, I can't really do this for you. It's not hard, just a lot of back-and-forth testing needs to be done. To do it solely in PL/SQL you need to monitor the alter_<sid>.log file for changes and filter the changed records for ORA- errors.. So, first step is to create, or get the dba to create a directory for that bdump directory. This will allow you to open the file for reading in PL/SQL
This is on an XE 10g database as SYSTEM user, with poly being the database user that is monitoring the file.
select value from v$parameter where name like 'background_dump_dest';
/usr/lib/oracle/xe/app/oracle/admin/XE/bdump
SQL> CREATE DIRECTORY BDUMP_DIR AS '/usr/lib/oracle/xe/app/oracle/admin/XE/bdump';
create directory succeeded.
SQL> grant read on directory alert_dir to poly;
grant read succeeded.After this, you need to read the file and search for ORA- messages. You use the UTL_FILE package to do this. The following subprograms in UTL_FILE will be useful to you.
Function: UTL_FILE.FOPEN You use this to open the file in readonly mode. Please look at the UTL_FILE documentation examples.
Procedure: UTL_FILE.GET_LINE You use this to read lines into PL/SQL
Procedure: UTL_FILE.GETATTR You use this to get the filelength. If the filelength is different from your previous call, you know some writes occurred.
Procedure UTL_FILE.FSEEK You use this to position the reading stream to the first byte of new data read. You've detected the file has grown in size and do something like utl_file.fseek(file_desc,last_file_length+1)
Procedure UTL_FILE.FCLOSE Close file when done.
Pseudologic:
This logic assumes you have a table which stores the filelength from the last time you executed the procedure. This allows you to only process records that have not already been processed.
1. Read last file length from persistent storage such as a table. Default to zero if no value.
2. Get filelength using UTL_FILE.GETATTR
3. Compare filelength. If equal to prior value, exit. If greater, than more lines added. If less, then dba must have rolled the log, reset prior filelength to zero to process entire new file.
4. Use UTL_FILE.FSEEK to position reader to one byte past last file length. This is why we default it to zero, 0+1=1.
5. Open file using UTL_FILE.FOPEN
6. Loop while data is avaliable, read each line, use instr or whatever to detect ORA- messages, call SMTP mailer as needed. You may want to log each email into a log table.
7. After loop, set persisted last file length (update a table and commit maybe) to value returned from UTL_FILE.FGETPOS.
8. Sleep for some interval of time. Start back at step 1.
You should consider using DBMS_SCHEDULER to set up this job.
There are lots of other ways of doing this. Remember that it's possible for your database to crash and your procedure might not be able to send an email. If someone edits the alter file and adds lines anywhere other than at the end, your program may resend some messages.
Edited by: david.sweet on Feb 19, 2011 10:16 AM: changed the word function to procedure for most of them