Apress.Expert.Oracle.Database.Architecture.9i.and.10g.Programming.Techniques.and.Solutions.Sep.2005

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CHAPTER 6 ■ LOCKING AND LATCHING
ops$tkyte@ORA10G> drop table dept;
Table dropped.
ops$tkyte@ORA10G> create table dept
2 (deptno, dname, loc, data,
3 constraint dept_pk primary key(deptno)
4 )
5 ROWDEPENDENCIES
6 as
7 select deptno, dname, loc, rpad('*',3500,'*')
8 from scott.dept;
Table created.
ops$tkyte@ORA10G> select deptno, dname,
2 dbms_rowid.rowid_block_number(rowid) blockno,
3 ora_rowscn
4 from dept;
DEPTNO DNAME
BLOCKNO ORA_ROWSCN
---------- -------------- ---------- ----------
10 ACCOUNTING 21020 34676364
20 RESEARCH 21020 34676364
30 SALES 21021 34676364
40 OPERATIONS 21021 34676364
We’re back where we were before: four rows on two blocks, all having the same initial
ORA_ROWSCN value. Now when we update DEPTNO=10
ops$tkyte@ORA10G> update dept
2 set dname = lower(dname)
3 where deptno = 10;
1 row updated.
ops$tkyte@ORA10G> commit;
Commit complete.
we should observe the following upon querying the DEPT table:
ops$tkyte@ORA10G> select deptno, dname,
2 dbms_rowid.rowid_block_number(rowid) blockno,
3 ora_rowscn
4 from dept;
DEPTNO DNAME
BLOCKNO ORA_ROWSCN
---------- -------------- ---------- ----------
10 accounting 21020 34676381
20 RESEARCH 21020 34676364
30 SALES 21021 34676364
40 OPERATIONS 21021 34676364