原来一直没注意,merge是可以支持delete,只不过必须的是on条件满足,也就是要求系统支持逻辑删除,而非物理删除。 Using the DELETE Clause with MERGE Statements You may want to cleanse tables while populating or updating them. To do this, you may want to consider using theDELETEclause in aMERGEstatement, ...
8. Thus when a row is updated inproducts, Oracle checks the delete conditionD.PROD_STATUS = "OBSOLETE", and deletes the row if the condition yields true. TheDELETEoperation is not as same as that of a completeDELETEstatement. Only the rows from the destination of theMERGEcan be deleted....
在Oracle数据库的使用中,向表中插入数据时,经常有这样的需求:如果待插入的记录表中已经存在,就用新记录的值更新原记录;如果不存在,就插入新记录。这时候,就需要用merge语句。通过merge语句能够避免自己手写好多if判断,程序简洁,更好维护。 merge语句的语法 MERGE INTO target_table USING source_table ON search_...
Oracle Database 11gリリース2(11.2.0.2)以降では、MERGEINTO操作を含むアプリケーションでポリシーを作成できます。そのためには、DBMS_RLS.ADD_POLICYstatement_typesパラメータにINSERT、UPDATEおよびDELETE文を含めるか、statement_typesパラメータを完全に省略します。特定のタイプのSQL文にポリシー...
Oracle Database 19c: Advanced SQL 3. DML: MERGE 3.1 Overview of DML Statements The five DML statements available in Oracle are INSERT, UPDATE, DELETE, MERGE and TRUNCATE. The first three are somewhatexplanatory. MERGE may not be. A MERGE statement will take one row source and merge it int...
The following illustrates the syntax of the OracleMERGEstatement: MERGEINTOtarget_tableUSINGsource_tableONsearch_conditionWHENMATCHEDTHENUPDATESETcol1 = value1, col2 = value2,...WHERE<update_condition> [DELETEWHERE<delete_condition>]WHENNOTMATCHEDTHENINSERT(col1,col2,...)values(value1,value2,.....
2、新增加的DELETE子句 Oracle 10g中的MERGE提供了在执行数据操作时清除行的选项.你能够在WHEN MATCHED THEN UPDATE子句中包含DELETE子句. DELETE子句必须有一个WHERE条件来删除匹配某些条件的行.匹配DELETE WHERE条件但不匹配ON条件的行不会被从表中删除.
In one aspect, the UPDATE clause of the MERGE statement is extended to include a conditional DELETE clause. Hence, records are deleted as appropriate based on a temporary updated state, as part of the same process as the update operation, without an additional table scan and without having to...
我有几个从ADO.NET代码在事务中执行的MERGE语句。mergeMyTable with (rowlock, updlock) as ton (t.values (...) then update set ... ;mergeSec 浏览0提问于2013-05-29得票数1 1回答 Server:合并后的非聚集索引(插入/更新) 、、 我是SQL Server的新手,我试图优化我从前同事那里得到的一个过程(我不能...
在Oracle 10g之前,merge语句支持匹配更新和不匹配插入2种简单的用法,在10g中Oracle对merge语句做了增强,增加了条件选项和DELETE操作。下面我通过一个demo来简单介绍一下10g中merge的增强和10g前merge的用法。 参考Oracle 的SQL Reference,大家可以看到Merge Statement的语法如下: ...