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новичок
участник
Last Login: 15.12.2000 22:41
Сообщ.: 1,
Visits: 12
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В какой последовательности работает?
Из table нужно выбрать 4 max.
SELECT C.CURR_NAME,TO_CHAR(C.RATE,''0.9'')"MAX RATE",C.RATE_DATE
FROM CURRENCY C
WHERE EXISTS( SELECT CURR_NAME,RATE,RATE_DATE
FROM CURRENCY
WHERE CURR_NAME=C.CURR_NAME
AND RATE_DATE=C.RATE_DATE
AND RATE>=C.RATE
HAVING COUNT(RATE)=4)
GROUP BY C.CURR_NAME,C.RATE,C.RATE_DATE;
Содержание :
CREATE TABLE CURRENCY
(CURR_NAME VARCHAR2(8),
RATE_DATE DATE,
RATE NUMBER(3,2)
);
INSERT INTO CURRENCY VALUES
(''DOLLAR'',''24-SEP-97'',1.3);
INSERT INTO CURRENCY VALUES
(''DOLLAR'',''24-SEP-97'',0.8);
INSERT INTO CURRENCY VALUES
(''DOLLAR'',''24-SEP-97'',1.8);
INSERT INTO CURRENCY VALUES
(''DOLLAR'',''24-SEP-97'',0.5);
INSERT INTO CURRENCY VALUES
(''DOLLAR'',''24-SEP-97'',0.4);
INSERT INTO CURRENCY VALUES
(''DOLLAR'',''24-SEP-97'',2.1);
INSERT INTO CURRENCY VALUES
(''DOLLAR'',''24-SEP-97'',0.3);
INSERT INTO CURRENCY VALUES
(''MARKA'',''24-SEP-97'',1.5);
INSERT INTO CURRENCY VALUES
(''MARKA'',''24-SEP-97'',1.0);
INSERT INTO CURRENCY VALUES
(''MARKA'',''24-SEP-97'',1.2);
INSERT INTO CURRENCY VALUES
(''MARKA'',''24-SEP-97'',0.7);
INSERT INTO CURRENCY VALUES
(''MARKA'',''24-SEP-97'',0.5);
INSERT INTO CURRENCY VALUES
(''MARKA'',''24-SEP-97'',0.2);
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новичок
участник
Last Login: 16.12.2000 13:39
Сообщ.: 3,
Visits: 34
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ошибок много
и вопрос конкретнее плиз
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