如何在 Azure 数据资源管理器/Kusto 中根据子字符串匹配连接两个表？

Question

我想根据数据表Fruit中具有子字符串匹配的单元格通过连接这两个表来创建一个结果表Things。

let Fruit = datatable(fruit:string) 
[
"apple", 
"banana" 
"orange" 
];
let Things = datatable(fruit:string) 
[
"anappletree",
"myoranges" 
];

我尝试过这样的事情：

Fruit
| join Things on $left.fruit contains $right.thing

但出现此错误：

Semantic Error 
join: only column entities or equality expressions are allowed in this context.

所以这里不能用contains。

我如何加入这个以便我可以获得一张包含以下内容的表格

"apple" | "anappletree"
"banana" | ""
"orange" | "myoranges"

Answer 1

join如果（在您的情况下 - ）的左侧Fruit足够小，您可以尝试使用mv-apply：

let Fruit = datatable(fruit:string) 
[
    "apple", 
    "banana",
    "orange" 
];
let Things = datatable(thing:string) 
[
    "anappletree",
    "myoranges",
    "this is not a fruit"
];
let Fruit_list = toscalar(Fruit | summarize make_list(fruit));
Things
| mv-apply fruit = Fruit_list on (where thing contains fruit)

事物	水果
一棵苹果树	苹果
橘子	橙子

或者，由于join在撰写本文时仅支持相等，您可以尝试使用交叉连接，然后使用以下方法进行过滤contains：

let Fruit = datatable(fruit:string) 
[
    "apple", 
    "banana",
    "orange" 
];
let Things = datatable(thing:string) 
[
    "anappletree",
    "myoranges",
    "this is not a fruit"
];
Fruit
| extend dummy = 1
| join kind=inner (Things | extend dummy = 1) on dummy
| where thing contains fruit
| project-away dummy*

水果	事物
苹果	一棵苹果树
橙子	橘子