问题描述
我想在kdb中加入字符串，但是效果不佳.这是数据:
I would like to join string in kdb but didn't work well. This is the data:
tab:([]service:`CS`CS.US`CS.US_ABC;y:1 2 3)
`CS 1
`CS.US 2
`CS.US_ABC 3
我想根据给定的参数添加:0和:primary. 0正在工作
I would like to add :0 and :primary depending on the given parameter. 0 is working now
update service:`$(((string[service],'(":"))),'("C"$string 0)) from tab
如果我希望数据成为
`CS:primary 1
`CS.US:primary 2
`CS.US_ABC:primary 3
主要是字符串或符号，我如何加入?
and the primary is either string or symbol, how could I join?
我正在参数化0和primary.
I am parameterizing the 0 and primary.
当前，0的工作方式如下
Currently, 0 works as follows
update service:`$(((string[service],'(":"))),'( "0")) from tab
但是主要"功能不起作用
but "primary" is not working
update service:`$(((string[service],'(":"))),'( "primary")) from tab
推荐答案
如果希望将primary作为参数而不是固定字符串，则可以使用以下命令(在此示例中primary为"no"):
If you want primary to be a parameter rather than a fixed string, the following will work (primary is "no" in this example):
q)update {`$string[y],\:":",x}[primary;]service from tab
service y
--------------
CS:no 1
CS.US:no 2
CS.US_ABC:no 3
如果primary是固定字符串，则可以将其放置在lambda中，以代替"x"，并将"y"替换为"x"，从而产生以下结果:
If primary is a fixed string then you can place it inside the lambda in lieu of "x" and replace "y" with "x", yielding the following:
q)update {`$string[x],\:":","primary"}service from tab
service y
-------------------
CS:primary 1
CS.US:primary 2
CS.US_ABC:primary 3
这篇关于如何在kdb中的表中联接字符串?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！