dataone;
inputyear qtr budget;
cards;
2001 3 500
2001 4 400
2003 1 350
;
run;
datatwo;
inputyear qtr sales;
cards;
2001 4 300
2002 1 600
;
run;
proc sql;
select one.*, sales from work.two left join work.one
on one.year=two.year;
quit;
问:left join是先把符合match条件的row拿出来,加上table one不符合条件的row也拿出来。那为何没有2003 1 350这条呢?
[td]year | qtr | budget | sales |
2001 | 3 | 500 | 300 |
2001 | 4 | 400 | 300 |
. | . | . | 600 |