Oracle中的Merge函数(批量更新/删除)
DEFINE TABLE : SCORE : using for save the students' score informations STUDENTS : the base information of students DEFINE COLUMNS : STUNO : the students' ID in theUniversity STUNAME : students' name COURSENAME : course name COURSESCORE : t
DEFINE TABLE :
SCORE : using for save the students' score informations
STUDENTS : the base information of students
DEFINE COLUMNS :
STUNO : the students' ID in the University
STUNAME : students' name
COURSENAME : course name
COURSESCORE : the study-results of the reference course
CLASSNAME : where the students study in
STUGRADE : the students grade
TERMNAME : the term which the reference course studied
NOW BEAGIN TO WRITE DOWN THE STATEMENT HERE BLOW THIS LINE !
MERGE INTO SCORE S
USING
(
SELECT A.*,B.*,? MYSCORE FROM SCORE A,STUDENT B
WHERE
A.CLASSNO=? AND A.GRADE=?
AND A.TERMNAME=? AND A.COURSENAME=?
A.STUNO=B.STUNO(+)
)X
ON
(S.STUNO=X.STUNO)
WHEN
MATHED
THEN
UPDATE SET COURSESCORE=X.MYSCORE
WHEN
NOT MATHED
THEN
INSERT
(
STUNO,STUNAME,COURSENAME,COURSESCORE,
CLASSNAME,STUGRADE,TERMNAME
)
VALUES
(
X.STUNO,X.STUNAME,X.COURSENAME,X.MYSCORE,
X.CLASSNAME,X.STUGRADE,X.TERMNAME
);
注意到 MERGE 语句在最后的“;”(分号),这仅仅带到 MERGE 为一条完整的 SQL 语句。
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