azure-data-explorer - Kusto 范围函数语义错误：'' 有以下语义错误：未解析的引用绑定：XXX"

Question

let a = (arg0:long) {
    toscalar(
        Incidents
        | where IncidentId == arg0 
        | count)
};
range idx from 0 to 11 step 1 
| extend a(idx)

我的 kusto 查询字符串就是这样的，而且很容易理解，但是它不起作用。

Answer 1

You're hitting limitations of user-defined functions, as they're documented here: https://docs.microsoft.com/en-us/azure/kusto/query/functions/user-defined-functions#restrictions-on-the-use-of-user-defined-functions

you should be able to achieve your goal by doing something like the following (matching the example you provided):

let count_by_incident_id = 
    Incidents 
    | summarize count() by IncidentId
;
range idx from 0 to 11 step 1
| join hint.strategy = broadcast (count_by_incident_id)
    on $left.idx == $right.IncidentId