Kdb 建议这样做问题是，我的数据集中有太多的列。有什么方法可以概括这一点吗？ id1 id2 exc1 exc2 exc3 exc4 "aa2" "12ac" 45 54 53 65 "bb" "23"

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建议这样做问题是，我的数据集中有太多的列。有什么方法可以概括这一点吗？

 id1     id2  exc1  exc2  exc3  exc4
 "aa2"   "12ac"   45     54   53     65 
 "bb"     "23"   23     33   23     12

kid1   id2   sf1   sf2  sf3   sf4  exc1 exc2
"aa2" "ads2"  55    6    55   66    45   54

t:([]id1:("aa2";"bb");id2:("12ac";"23");exc1:45 23; exc2:54 33;exc3:53 23;exc4:65 12)
q:([]kid:enlist "aa2";id2:enlist "ads2";sf1:(),55;sf2:(),6;sf3:(),55;sf4:(),66;exc1:(),45;exc2:(),54)

rt:`link xkey update link:`$"|"sv/:flip(id1;id2),id1:`$id1,id2:`$id2 from t
rq:`link xkey update link:`$"|"sv/:flip(kid;id2),kid:`$kid,id2:`$id2 from q

q)rt uj rq
link     | id1   id2    exc1 exc2 exc3 exc4 kid   sf1 sf2 sf3 sf4
---------| ------------------------------------------------------
aa2|12ac | "aa2" "12ac" 45   54   53   65   ""
bb|23    | "bb"  "23"   23   33   23   12   ""
aa2|ads2 | ""    "ads2" 45   54             "aa2" 55  6   55  66

q)(2!data1) uj `id1`id2 xkey update id1:kid1 from data2
id1   id2   | exc1 exc2 exc3 exc4 kid1  sf1 sf2 sf3 sf4
------------| -----------------------------------------
"aa2" "12ac"| 45   54   53   65   ""
"bb"  "23"  | 23   33   23   12   ""
"aa2" "ads2"| 45   54             "aa2" 55  6   55  66

q)t:(2!data1) uj `id1`id2 xkey update id1:kid1 from data2   //same as before
q)(t lj 1!select id1,exc2,exc3 from data1)^t                //lj these fields on, use fill to only update null fields
id1   id2   | exc1 exc2 exc3 exc4 kid1  sf1 sf2 sf3 sf4
------------| -----------------------------------------
"aa2" "12ac"| 45   54   53   65   ""
"bb"  "23"  | 23   33   23   12   ""
"aa2" "ads2"| 45   54   53        "aa2" 55  6   55  66
q)cols[data1]#0!(t lj 1!select id1,exc2,exc3 from data1)^t  //use Ryan's suggestion for getting the cols you desire
id1   id2    exc1 exc2 exc3 exc4
--------------------------------
"aa2" "12ac" 45   54   53   65
"bb"  "23"   23   33   23   12
"aa2" "ads2" 45   54   53