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DB/ORACLE

implicit query

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An implicit query is a component of a DML statement that retrieves data without using a subquery.

An UPDATE, DELETE, or MERGE statement that does not explicitly include a SELECT statement uses

an implicit query to retrieve rows to be modified. For example, the following statement includes

an implicit query for the Baer record:

 

UPDATE employees 
SET salary = salary*1.1 
WHERE last_name = 'Baer';


The only DML statement that does not necessarily include a query component is an INSERT statement

with a VALUES clause. For example, an INSERT INTO TABLE mytable VALUES (1) statement does not retrieve

rows before inserting a row.

 

출처 : http://download.oracle.com/docs/cd/E11882_01/server.112/e16508/sqllangu.htm#CNCPT88907

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