KDB/Q：如何合并多列的值并排序？

Question

我想创建一个包含多列值的新列，但这些值会被排序。请参阅下面的示例 table。并且列的类型是 C

name1   name2       name3       wanted
David   Barca       Alpha       Alpha Barca David
Sydney  Melbourne   Adelaide    Adelaide Melbourne Sydney
1201    21204       5601        1201 21204 5601

Answer 1

q)update wanted: " " sv/: asc each flip (name1;name2;name3) from t
name1    name2       name3      wanted
-----------------------------------------------------------
"David"  "Barca"     "Alpha"    "Alpha Barca David"
"Sydney" "Melbourne" "Adelaide" "Adelaide Melbourne Sydney"
"1201"   "21204"     "5601"     "1201 21204 5601"

如果您 wanted 是嵌套列表而不是单个字符串，则可以省略 sv 部分：

q)update wanted: asc each flip (name1;name2;name3) from t
name1    name2       name3      wanted
---------------------------------------------------------------
"David"  "Barca"     "Alpha"    "Alpha"    "Barca"     "David"
"Sydney" "Melbourne" "Adelaide" "Adelaide" "Melbourne" "Sydney"
"1201"   "21204"     "5601"     "1201"     "21204"     "5601"

KDB/Q：如何合并多列的值并排序？

KDB/Q: how to combine the values in multiple columns and sort the values?

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