SELECT
CASE
WHEN A.TYPE='SUTDENT' THEN
A.NAME,A.AGE,B.GRADE
WHEN A.TYPE='TEACHER' THEN
A.NAME,A.AGE,C.GRADE
END
FROM PERSON A,STUDENT B,TEACHER C
WHERE A.PID=B.PID AND A.PID=C.PID
这个提示 A.NAME 这儿缺少关键字 怎么回事啊
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急啊 SELECT CASE
SELECT CASE WHEN A.TYPE='SUTDENT' THEN A.NAME,A.AGE,B.GRADE WHEN A.TYPE='TEACHER' THEN A.NAME,A.AGE,C.GRADE END FROM PERSON A,STUDENT B,TEACHER C WHERE A.PID=B.PID AND A.PID=C.PID 这个提示 A.NAME 这儿缺少关键字 怎么回事啊
[Quote=引用楼主 how8586 的回复:]
SELECT
CASE
WHEN A.TYPE='SUTDENT' THEN
A.NAME,A.AGE,B.GRADE
WHEN A.TYPE='TEACHER' THEN
A.NAME,A.AGE,C.GRADE
END
FROM PERSON A,STUDENT B,TEACHER C
WHERE A.PID=B.PID AND A.PID……
[/Quote]
SELECT
CASE WHEN A.TYPE='SUTDENT' THEN A.NAME||','||A.AGE||',||B.GRADE
WHEN A.TYPE='TEACHER' THEN A.NAME||','||A.AGE||','||C.GRADE END
FROM PERSON A,STUDENT B,TEACHER C
WHERE A.PID=B.PID AND A.PID=C.PID
SELECT
A.NAME,A.AGE,
CASE
WHEN A.TYPE='SUTDENT' THEN
B.GRADE
WHEN A.TYPE='TEACHER' THEN
C.GRADE
END case
FROM PERSON A,STUDENT B,TEACHER C
WHERE A.PID=B.PID AND A.PID=C……
[/Quote]
SELECT
A.NAME,A.AGE,
CASE
WHEN A.TYPE='SUTDENT' THEN
B.GRADE
WHEN A.TYPE='TEACHER' THEN
C.GRADE
END case
FROM PERSON A,STUDENT B,TEACHER C
WHERE A.PID=B.PID AND A.PID=C.PID