默認情況下，oracle的分區(qū)表對于分區(qū)字段是不允許進行update操作的，如果有對分區(qū)字段行進update，就會報錯——ORA-14402: 更新分區(qū)關鍵字列將導致分區(qū)的更改。但是可以通過打開表的row movement屬性來允許對分區(qū)字段的update操作。
例：創(chuàng)建分區(qū)表test_part進行實驗
create table TEST_PART
(
A1 NUMBERnot null,
A2 DATE not null,
A3 VARCHAR2(6) not null,
A4 DATE not null,
A5 NUMBER not null,
)
partition by range (A1)
(
partition P1 values less than (1000),
partition P2 values less than (2000),
partition P3 values less than (3000),
partition P4 values less than (4000),
partition P5 values less than (5000),
partition P6 values less than (MAXVALUE)
);
插入如下的數據
SQL> select * from test_part;
A1 A2 A3 A4 A5
---------- ----------- ------ ----------- ----------
123 2006-06-30 123456 2006-06-30 123
456 2006-06-30 asdfgh 2006-06-30 456
1 2006-06-30 234123 2006-06-30 1
2 2006-06-30 234234 2006-06-30 2
1234 2006-06-30 456789 2006-06-30 1234
1111 2006-06-30 ewrqwe 2006-06-30 1111
2222 2006-06-30 fdafda 2006-06-30 2222
3333 2006-06-30 342342 2006-06-30 3333
5678 2006-06-30 qwerty 2006-06-30 5678
9 rows selected
分區(qū)P1、P2的數據分別為：
SQL> select rowid,t.* from test_part partition(p1) t;
ROWID A1 A2 A3 A4 A5
------------------ ---------- ----------- ------ ----------- ----------
AAAGLoAAGAAAtsEAAB 456 2006-06-30 asdfgh 2006-06-30 456
AAAGLoAAGAAAtsEAAC 1 2006-06-30 234123 2006-06-30 1
AAAGLoAAGAAAtsEAAD 2 2006-06-30 234234 2006-06-30 2
AAAGLoAAGAAAtsEAAE 123 2006-06-30 123456 2006-06-30 123
SQL> select rowid,t.* from test_part partition(p2) t;
ROWID A1 A2 A3 A4 A5
------------------ ---------- ----------- ------ ----------- ----------
AAAGLwAAGAAA+8MAAC 1234 2006-06-30 456789 2006-06-30 1234
AAAGLwAAGAAA+8MAAD 1111 2006-06-30 ewrqwe 2006-06-30 1111
直接update提示錯誤
SQL> update test_part set a1=1123 where a1=123;
update test_part set a1=1123 where a1=123
ORA-14402: 更新分區(qū)關鍵字列將導致分區(qū)的更改
打開row movement屬性
SQL> alter table test_part enable row movement;
Table altered
再次執(zhí)行update操作
SQL> update test_part set a1=1123 where a1=123;
1 row updated
執(zhí)行是成功的并遷移到分區(qū)P2上了，且這時候rowid也發(fā)生了變化
SQL> select rowid,t.* from test_part partition(p2) t;
ROWID A1 A2 A3 A4 A5
------------------ ---------- ----------- ------ ----------- ----------
AAAGLwAAGAAA+8MAAC 1234 2006-06-30 456789 2006-06-30 1234
AAAGLwAAGAAA+8MAAD 1111 2006-06-30 ewrqwe 2006-06-30 1111
AAAGLwAAGAAA+8PAAB 1123 2006-06-30 123456 2006-06-30 123
SQL>
enable row movement可以允許數據段的壓縮、update分區(qū)字段的數據（跨分區(qū)的）
但是，也是有限制性的：對于普通表（heap-organized）行遷移后rowid會發(fā)生變化，對于索引表（index-organized）rowid雖然依然有效，但是其實際對應的物理構成是錯誤的。
