Pausing and resuming a PL/SQL proc from oracle PL/SQL DEVELOPER tool

Question

I need to test a PL/SQL on how it reacts to an exception. I need to PAUSE it, do something outside of the proc and then resume the proc. Is there a PROMPT command in PL/SQL where it would wait for user input? Can I use DBMS_OUTPUT.GET_LINE to do this? Where does the GET_LINE raed its input from?

Answer 1

Perhaps the following demo will help. It uses straight SQL, since the PRIMARY KEY stuff does not require any sort of PL/SQL.
I set up 2 sessions in SQLPlus.
Session 1 - create a table with a primary key, insert and do not commit:
session 1:
C:\Users\Hans>sqlplus test/test
SQL*Plus: Release 10.2.0.1.0 - Production on Sat Oct 10 15:40:13 2009
Copyright (c) 1982, 2005, Oracle.  All rights reserved.
Connected to:
Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
SQL> create table abc ( a number primary key enable);
Table created.
SQL> insert into abc values (1);
1 row created.Go to session 2 and insert:
C:\Users\Hans>sqlplus test/test
SQL*Plus: Release 10.2.0.1.0 - Production on Sat Oct 10 15:36:45 2009
Copyright (c) 1982, 2005, Oracle.  All rights reserved.
Connected to:
Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production
SQL> insert into abc values (1);it hangs here.
Switch back to session 1 and commit;
SQL> commit;
Commit complete.
SQL>and in session 2 I see
insert into abc values (1)
ERROR at line 1:
ORA-00001: unique constraint (TEST.SYS_C006468) violated
SQL>Trying this for different test cases: session 1 insert value (2) and session s, insert value (3)
Session 1
SQL> insert into abc values (2);
1 row created.
SQL>Session 2
SQL> insert into abc values (3);
1 row created.
SQL>Back to session 1
SQL> commit;
Commit complete.
SQL>Back to session 2
SQL> insert into abc values (3);
1 row created.
SQL>So I conclude that dups will block during insert.
For your original question - SQL and PL/SQL are run in separate engines. PL/SQL sends the SQL command to the SQL engine, which runs that and returns any return info (rowset, error, ...).
So any questions about SQL and SQL transaction control may be handled in a purely SQLPlus (or TOAD or SQLDeveloper) test case.
OTOH, questions about PL/SQL can be answered using a debug environment such as SQLDeveloper - see http://www.oracle.com/technology/obe/sqldev/plsql_debug/plsql_debug.htm