一个最小的例子:
DATA my_data;
INPUT id name $;
DATALINES;
10 Adam
20 Bob
;
DATA my_data2;
INPUT id name $ value year;
DATALINES;
10 Adam 100 2010
10 Adam 200 2017
20 Bob 300 2010
20 Bob 400 2017
;
PROC SQL;
CREATE TABLE TEST AS
SELECT A.ID, A.NAME,
CASE WHEN B.YEAR = 2010 THEN B.VALUE ELSE . END,
CASE WHEN B.YEAR = 2017 THEN B.VALUE ELSE . END
FROM MY_DATA A
LEFT JOIN MY_DATA2 B ON A.ID = B.ID AND A.NAME = B.NAME
;
QUIT;
我得到的输出是:
10 Adam 100 .
10 Adam . 200
20 Bob 300 .
20 Bob . 400
但是我想要的输出是:
10 Adam 100 200
20 Bob 300 400
我知道联接是问题所在,但我不是100%应该采用这种方法。
答案 0 :(得分:2)
针对ID和NAME列以及著名的聚合函数使用GROUPING
( MIN 或 MAX ):
SELECT A.ID, A.NAME,
MIN(CASE WHEN B.YEAR = 2010 THEN B.VALUE ELSE NULL END) VALUE1,
MIN(CASE WHEN B.YEAR = 2017 THEN B.VALUE ELSE NULL END) VALUE2
FROM MY_DATA A
LEFT JOIN MY_DATA2 B ON A.ID = B.ID AND A.NAME = B.NAME
GROUP BY A.ID, A.NAME
ORDER BY A.ID
答案 1 :(得分:0)
感谢@EzLo。
PROC SQL;
CREATE TABLE TEST AS
SELECT A.ID, A.NAME,
MAX(CASE WHEN B.YEAR = 2010 THEN B.VALUE ELSE . END),
MAX(CASE WHEN B.YEAR = 2017 THEN B.VALUE ELSE . END)
FROM MY_DATA A
LEFT JOIN MY_DATA2 B ON A.ID = B.ID AND A.NAME = B.NAME
GROUP BY A.ID, A.NAME
;
QUIT;