{"id":1521,"date":"2018-11-19T18:28:07","date_gmt":"2018-11-19T10:28:07","guid":{"rendered":"https:\/\/yangtingkun.net\/?p=1521"},"modified":"2018-11-19T18:28:07","modified_gmt":"2018-11-19T10:28:07","slug":"undo%e6%9e%84%e9%80%a0%e4%b8%80%e8%87%b4%e6%80%a7%e8%af%bb%e7%9a%84%e4%be%8b%e5%a4%96%e6%83%85%e5%86%b5","status":"publish","type":"post","link":"https:\/\/yangtingkun.net\/?p=1521","title":{"rendered":"Undo\u6784\u9020\u4e00\u81f4\u6027\u8bfb\u7684\u4f8b\u5916\u60c5\u51b5"},"content":{"rendered":"

\u5609\u5e74\u534e\u542c\u4e86\u6069\u58a8\u5b66\u9662\u7684\u4e00\u4e2a\u4e3b\u9898\uff1a\u300a\u91cd\u73b0ORA-01555 \u7ec6\u8bf4Oracle 12c Undo\u6570\u636e\u7ba1\u7406\u300b\uff0c\u5415\u8001\u5e08\u4ecb\u7ecd\u4e86UNDO\u7684\u6982\u5ff5\u4ee5\u53caORA-1555\u7684\u4ea7\u751f\uff0c\u5e76\u4ecb\u7ecd\u4e8612c\u4ee5\u6765Oracle\u7684UNDO\u76f8\u5173\u7684\u65b0\u7279\u6027\u3002<\/span><\/p>\n

\u5176\u4e2d\u4ecb\u7ecd\u4e86Oracle\u5982\u4f55\u4f7f\u7528UNDO\u6765\u5b9e\u73b0\u591a\u7248\u672c\u4e00\u81f4\u6027\u8bfb\uff0c\u4f7f\u7528\u4e86OPEN CURSOR\u7684\u65b9\u5f0f\u975e\u5e38\u5de7\u5999\u5730\u5728\u5f88\u5c11\u91cf\u6570\u636e\u7684\u60c5\u51b5\u4e0b\u6784\u9020\u51fa\u53ef\u91cd\u73b0\u7684\u6848\u4f8b\u3002\u4e0d\u8fc7\u8fd9\u4e2a\u6848\u4f8b\u5b58\u5728\u4e00\u70b9\u5c0f\u7684\u7455\u75b5\uff0c\u56e0\u4e3a\u5982\u679c\u4e00\u4e0d\u5c0f\u5fc3\uff0c\u5f88\u53ef\u80fd\u4f1a\u5bfc\u81f4\u7ed3\u679c\u4e0e\u9884\u671f\u4e0d\u7b26\uff0c\u8fd9\u662f\u56e0\u4e3a\u8fd9\u91cc\u6709\u4e00\u4e2a\u4f8b\u5916\u5b58\u5728\u3002<\/span><\/p>\n

\u6211\u4eec\u5148\u6765\u6a21\u62df\u4e00\u4e0bUNDO\u6784\u9020\u4e00\u81f4\u6027\u8bfb\u7684\u60c5\u51b5\uff0c\u5bf9\u4e8eOracle\u800c\u8a00\uff0c\u9ed8\u8ba4\u7684\u9694\u79bb\u7ea7\u522b\u662fREAD COMMIT\uff0c\u4e5f\u5c31\u662f\u8bf4\u4e00\u4e2a\u4f1a\u8bdd\u53ea\u80fd\u770b\u5230\u5176\u4ed6\u4f1a\u8bdd\u5df2\u7ecf\u63d0\u4ea4\u7684\u4fee\u6539\uff0c\u672a\u63d0\u4ea4\u7684\u4fee\u6539\u6216\u8005\u5728\u5f53\u524d\u4f1a\u8bdd\u67e5\u8be2\u53d1\u8d77\u4e4b\u540e\u63d0\u4ea4\u7684\u4fee\u6539\u90fd\u662f\u4e0d\u53ef\u89c1\u7684\u3002<\/span><\/p>\n

\u518d\u4ecb\u7ecd\u4e00\u4e0bOPEN CURSOR\uff0cOracle\u4e2d\u5f53\u4e00\u4e2a\u6e38\u6807\u88ab\u6253\u5f00\uff0c\u5176\u7ed3\u679c\u96c6\u5c31\u5df2\u7ecf\u786e\u5b9a\u4e86\uff0c\u4e5f\u5c31\u662f\u8bf4\u8fd9\u4e2a\u6e38\u6807\u4f1a\u6839\u636eOPEN CURSOR\u8fd9\u4e2a\u65f6\u95f4\u70b9\u5bf9\u5e94\u7684SCN\u6765\u6784\u9020\u4e00\u81f4\u6027\u67e5\u8be2\u3002\u4f46\u662fOPEN CURSOR\u65f6\uff0c\u5bf9\u5e94\u7684SQL\u5e76\u4e0d\u4f1a\u88ab\u6267\u884c\uff0c\u5728\u540e\u7eedFETCH\u7684\u65f6\u5019\uff08\u5bf9\u4e8eSQLPLUS\u800c\u8a00PRINT\u547d\u4ee4\u4f1a\u89e6\u53d1FETCH\uff09\uff0cSQL\u624d\u771f\u6b63\u88ab\u6267\u884c\u3002\u4f7f\u7528\u8fd9\u79cd\u529e\u6cd5\u53ef\u4ee5\u6a21\u62df\u4e00\u4e2a\u5927\u7684\u67e5\u8be2\uff0cOPEN CURSOR\u76f8\u5f53\u4e8e\u5927\u7684\u67e5\u8be2\u7684\u5f00\u59cb\u65f6\u95f4\uff0c\u5176\u65e9\u4e8e\u5176\u4ed6\u4f1a\u8bdd\u7684\u4fee\u6539\u63d0\u4ea4\u65f6\u95f4\uff0c\u800cFETCH\u7684\u65f6\u95f4\u76f8\u5f53\u4e8e\u5927\u67e5\u8be2\u8bfb\u53d6\u5230\u8fd9\u6761\u8bb0\u5f55\u7684\u65f6\u95f4\uff0c\u800c\u8be5\u65f6\u95f4\u665a\u4e8e\u5176\u4ed6\u4f1a\u8bdd\u63d0\u4ea4\u7684\u65f6\u95f4\uff1a<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL> SET SQLP ‘SQL1> ‘<\/span><\/p>\n

SQL1> CREATE TABLE T_UNDO (ID NUMBER, NAME VARCHAR2(30));<\/span><\/p>\n

\u00a0<\/span><\/p>\n

Table created.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> INSERT INTO T_UNDO SELECT ROWNUM, OBJECT_NAME FROM DBA_OBJECTS;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

96920 rows created.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> COMMIT;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

Commit complete.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> CREATE INDEX IND_UNDO_ID ON T_UNDO(ID);\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span><\/span><\/p>\n

\u00a0<\/span><\/p>\n

Index created.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> SELECT NAME FROM T_UNDO WHERE ID = 1119;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

NAME<\/span><\/p>\n

————————————————————<\/span><\/p>\n

I_EXTERNAL_LOCATION1$<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> VAR C REFCURSOR <\/span><\/p>\n

SQL1> EXEC OPEN :C FOR SELECT NAME FROM T_UNDO WHERE ID = 1119;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

PL\/SQL procedure successfully completed.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

\u5728\u7b2c\u4e00\u4e2a\u4f1a\u8bdd\u5df2\u7ecf\u6784\u9020\u4e86\u4e00\u4e2a\u67e5\u8be2\uff0c\u4e0b\u9762\u5728\u4f1a\u8bdd2\u5bf9\u8fd9\u6761ID\u4e3a1119\u7684\u8bb0\u5f55\u8fdb\u884c\u4fee\u6539\u5e76\u63d0\u4ea4\uff1a<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL> SET SQLP ‘SQL2> ‘<\/span><\/p>\n

SQL2> UPDATE T_UNDO SET NAME = ‘UPDATED’ WHERE ID = 1119;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

1 row updated.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL2> COMMIT;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

Commit complete.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

\u5728\u4f1a\u8bdd3\u4e0a\u6267\u884c\u67e5\u8be2\uff0c\u8fd9\u65f6\u4f1a\u770b\u5230\u4f1a\u8bdd2\u4fee\u6539\u63d0\u4ea4\u540e\u7684\u7ed3\u679c\uff1a<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL> SET SQLP ‘SQL3> ‘<\/span><\/p>\n

SQL3> SELECT NAME FROM T_UNDO WHERE ID = 1119;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

NAME<\/span><\/p>\n

————————————————————<\/span><\/p>\n

UPDATED<\/span><\/p>\n

\u00a0<\/span><\/p>\n

\u56de\u5230\u4f1a\u8bdd1\uff0c\u5bf9CURSOR\u53d8\u91cf\u6267\u884cPRINT\uff0c\u68c0\u67e5\u5f97\u5230\u7684\u7ed3\u679c\uff1a<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> PRINT :C\u00a0 <\/span><\/span><\/p>\n

\u00a0<\/span><\/p>\n

NAME<\/span><\/p>\n

————————————————————<\/span><\/p>\n

I_EXTERNAL_LOCATION1$<\/span><\/p>\n

\u00a0<\/span><\/p>\n

\u5230\u76ee\u524d\u4e3a\u6b62\uff0c\u6240\u6709\u90fd\u662f\u9884\u671f\u4e4b\u5185\u7684\u7ed3\u679c\uff0cOracle\u4f1a\u5229\u7528UNDO\u6765\u5b58\u50a8UPDATE\u7684\u524d\u955c\u50cf\uff0c\u5f53\u67e5\u8be2\u53d1\u73b0\u9700\u8981\u8bbf\u95ee\u7684\u6570\u636e\u5757SCN\u5927\u4e8e\u4f1a\u8bdd\u53d1\u8d77\u7684SCN\uff0c\u800c\u9700\u8981\u901a\u8fc7UNDO\u4e2d\u5b58\u50a8\u7684\u524d\u955c\u50cf\u6765\u6784\u9020\u4e00\u81f4\u6027\u8bfb\uff0c\u627e\u5230\u4f1a\u8bdd\u9700\u8981\u8bfb\u53d6\u7684\u4fee\u6539\u524d\u7684\u6570\u636e\u3002<\/span><\/p>\n

\u90a3\u4e48\u4f8b\u5916\u6765\u81ea\u54ea\u91cc\u5462\uff0c\u5728\u8fd9\u4e2a\u4f8b\u5b50\u4e2d\uff0c\u6211\u4eec\u7ed9ID\u5217\u4e0a\u521b\u5efa\u4e86\u4e00\u4e2a\u7d22\u5f15\uff0c\u5982\u679c\u8fd9\u4e0d\u662f\u4e00\u4e2a\u666e\u901a\u7684\u7d22\u5f15\uff0c\u800c\u662f\u4e00\u4e2a\u4e3b\u952e\uff0c\u90a3\u4e48\u6548\u679c\u5982\u4f55\u5462\uff1a<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> DROP INDEX IND_UNDO_ID;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

Index dropped.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> ALTER TABLE T_UNDO ADD PRIMARY KEY (ID);<\/span><\/p>\n

\u00a0<\/span><\/p>\n

Table altered.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> SELECT NAME FROM T_UNDO WHERE ID = 1118;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

NAME<\/span><\/p>\n

————————————————————<\/span><\/p>\n

EXTERNAL_LOCATION$<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> EXEC OPEN :C FOR SELECT NAME FROM T_UNDO WHERE ID = 1118;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

PL\/SQL procedure successfully completed.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

\u4f1a\u8bdd2\u4fee\u6539ID\u4e3a1118\u7684\u8bb0\u5f55\uff1a<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL2> UPDATE T_UNDO SET NAME = ‘UPDATED WITH PK’ WHERE ID = 1118;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

1 row updated.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL2> COMMIT;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

Commit complete.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

\u4f1a\u8bdd3\u68c0\u67e5\u786e\u8ba4\u4fee\u6539\u7ed3\u679c\uff1a<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL3> SELECT NAME FROM T_UNDO WHERE ID = 1118;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

NAME<\/span><\/p>\n

—————<\/span><\/p>\n

UPDATED WITH PK<\/span><\/p>\n

\u00a0<\/span><\/p>\n

\u518d\u6b21\u56de\u5230\u4f1a\u8bdd1\uff0cPRINT\u6e38\u6807\u53d8\u91cf\uff1a<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> PRINT :C<\/span><\/p>\n

\u00a0<\/span><\/p>\n

NAME<\/span><\/p>\n

————————————————————<\/span><\/p>\n

UPDATED WITH PK<\/span><\/p>\n

\u00a0<\/span><\/p>\n

\u53ef\u4ee5\u770b\u5230\u4f8b\u5916\u4ea7\u751f\u4e86\uff0c\u4e00\u81f4\u6027\u8bfb\u7684\u7ed3\u679c\u88ab\u7834\u574f\u4e86\uff0c\u5c45\u7136\u53ef\u4ee5\u67e5\u8be2\u5230\u53d1\u751f\u5728\u6e38\u6807\u6253\u5f00\u4e4b\u540e\u63d0\u4ea4\u7684\u4fee\u6539\u3002<\/span><\/p>\n

\u5bfc\u81f4\u8fd9\u4e2a\u4f8b\u5916\u7684\u539f\u56e0\u6765\u81ea\u4e8e\u4e00\u4e2a\u9690\u542b\u51fd\u6570_row_cr\uff1a<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL> SELECT KSPPINM NAME, KSPPSTVL VALUE, KSPPDESC DESCRIPTION<\/span><\/p>\n

\u00a0 <\/span>2\u00a0 <\/span>FROM SYS.X$KSPPI X, SYS.X$KSPPCV Y<\/span><\/p>\n

\u00a0 <\/span>3\u00a0 <\/span>WHERE X.INDX = Y.INDX<\/span><\/p>\n

\u00a0 <\/span>4 \u00a0<\/span>AND KSPPINM = ‘_row_cr’;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

NAME\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0VALUE\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span>DESCRIPTION<\/span><\/p>\n

————— ————— ————————————————–<\/span><\/p>\n

_row_cr\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span>TRUE\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <\/span>enable row cr for all sql<\/span><\/p>\n

\u00a0<\/span><\/p>\n

Oracle11g\u4ee5\u540e\uff0c\u8fd9\u4e2a\u9690\u542b\u53c2\u6570\u9ed8\u8ba4\u503c\u4fee\u6539\u4e3aTRUE\uff0c\u8fd9\u4f7f\u5f97Oracle\u5bf9\u4e8e\u57fa\u4e8e\u4e3b\u952e\u7684\u8bbf\u95ee\u4e0d\u518d\u91c7\u7528\u9ed8\u8ba4\u7684\u4e00\u81f4\u6027\u8bfb\u65b9\u6848\u3002\u5f53\u7136Oracle\u505a\u51fa\u8fd9\u79cd\u4fee\u6539\u7684\u76ee\u7684\u662f\u4e3a\u4e86\u63d0\u9ad8\u6027\u80fd\uff0c\u800c\u4e14\u4ec5\u5bf9\u4e8e\u5355\u884c\u8bbf\u95ee\u751f\u6548\uff0c\u800c\u5927\u90e8\u5206\u60c5\u51b5\u4e0b\u5355\u884c\u8bbf\u95ee\u7684\u6548\u7387\u975e\u5e38\u9ad8\uff0c\u56e0\u6b64\u5bf9\u4e8e\u4e00\u81f4\u6027\u7834\u574f\u7684\u5f71\u54cd\u5e76\u4e0d\u660e\u663e\u3002\u523018C\u4e3a\u6b62\uff0c\u8be5\u53c2\u6570\u4ecd\u7136\u4e3aTRUE\u3002<\/span><\/span><\/p>\n

\u5982\u679c\u5173\u95ed\u8be5\u53c2\u6570\uff1a<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> ALTER SYSTEM SET “_row_cr” = FALSE;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

System altered.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> SELECT NAME FROM T_UNDO WHERE ID = 1117;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

NAME<\/span><\/p>\n

————————————————————<\/span><\/p>\n

I_EXTERNAL_TAB1$<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> EXEC OPEN :C FOR SELECT NAME FROM T_UNDO WHERE ID = 1117;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

PL\/SQL procedure successfully completed.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

\u4f1a\u8bdd2\u8fdb\u884c\u4fee\u6539\uff1a<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL2> UPDATE T_UNDO SET NAME = ‘UPDATED NO ROW CR’ WHERE ID = 1117;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

1 row updated.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL2> COMMIT;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

Commit complete.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

\u68c0\u67e5\u7ed3\u679c\uff1a<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL3> SELECT NAME FROM T_UNDO WHERE ID = 1117;<\/span><\/p>\n

\u00a0<\/span><\/p>\n

NAME<\/span><\/p>\n

——————<\/span><\/p>\n

UPDATED NO ROW CR<\/span><\/p>\n

\u00a0<\/span><\/p>\n

\u56de\u5230\u4f1a\u8bdd1\u68c0\u67e5\u7ed3\u679c\uff1a<\/span><\/p>\n

\u00a0<\/span><\/p>\n

SQL1> PRINT :C<\/span><\/p>\n

\u00a0<\/span><\/p>\n

NAME<\/span><\/p>\n

————————————————————<\/span><\/p>\n

I_EXTERNAL_TAB1$<\/span><\/p>\n

\u00a0<\/span><\/p>\n

Oracle\u6062\u590d\u9ed8\u8ba4\u7684\u8bfb\u4e00\u81f4\u6027\u9694\u79bb\u7ea7\u522b\u3002<\/span><\/span><\/p>\n

\u867d\u7136Oracle\u8ba4\u4e3a\u8fd9\u79cd\u4f18\u5316\u53ea\u662f\u9488\u5bf9\u4e3b\u952e\u6216\u552f\u4e00\u7d22\u5f15\u7b49\u884c\u7ea7\u8bbf\u95ee\u751f\u6548\uff0c\u9020\u6210\u6570\u636e\u4e00\u81f4\u6027\u7834\u574f\u7684\u53ef\u80fd\u6027\u5f88\u5c0f\uff0c\u4f46\u662f\u5efa\u8bae\u5bf9\u4e8e\u4e00\u81f4\u6027\u8981\u6c42\u8f83\u9ad8\u7684\u884c\u4e1a\u5c24\u5176\u662f\u91d1\u878d\u76f8\u5173\u884c\u4e1a\u8fd8\u662f\u5c06\u8be5\u7279\u6027\u5173\u95ed\uff0c\u907f\u514d\u56e0\u6b64\u9020\u6210\u7684\u4e00\u81f4\u6027\u95ee\u9898\u3002<\/span><\/p>\n

\u00a0<\/span><\/p>\n

\u00a0<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"

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