SQL 到 Kusto 查詢語言 速查表

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如果您熟悉 SQL 並想要瞭解 KQL，請使用批注行 --和 關鍵詞 explain前置 SQL 查詢，將 SQL 查詢轉譯成 KQL。 輸出會顯示查詢的 KQL 版本，可協助您瞭解 KQL 語法和概念。

執行查詢

--
explain
SELECT COUNT_BIG(*) as C FROM StormEvents

輸出

查詢
StormEvents<br>| summarize C=count () <br>| project C

SQL 對 Kusto 的功能提要

下表顯示 SQL 中的範例查詢及其 KQL 對等專案。

類別 SQL 查詢 Kusto 查詢 深入了解
從資料表選取資料 SELECT * FROM dependencies dependencies 表格式運算式陳述式
-- SELECT name, resultCode FROM dependencies dependencies | project name, resultCode project
-- SELECT TOP 100 * FROM dependencies dependencies | take 100 take
Null 評估 SELECT * FROM dependencies
WHERE resultCode IS NOT NULL		 dependencies
| where isnotnull(resultCode)		 isnotnull()
比較運算子 (日期) SELECT * FROM dependencies
WHERE timestamp > getdate()-1		 dependencies
| where timestamp > ago(1d)		 ago()
-- SELECT * FROM dependencies
WHERE timestamp BETWEEN ... AND ...		 dependencies
| where timestamp between (datetime(2016-10-01) .. datetime(2016-11-01))		 between
比較運算子 (字串) SELECT * FROM dependencies
WHERE type = "Azure blob"		 dependencies
| where type == "Azure blob"		 邏輯運算子
-- -- substring
SELECT * FROM dependencies
WHERE type like "%blob%"		 // substring
dependencies
| where type has "blob"		 Hsa
-- -- wildcard
SELECT * FROM dependencies
WHERE type like "Azure%"		 // wildcard
dependencies
| where type startswith "Azure"
// or
dependencies
| where type matches regex "^Azure.*"		 startswith
符合 regex
比較 (布林值) SELECT * FROM dependencies
WHERE !(success)		 dependencies
| where success == False		 邏輯運算子
群組，彙總 SELECT name, AVG(duration) FROM dependencies
GROUP BY name		 dependencies
| summarize avg(duration) by name		 總結
avg ()
Distinct SELECT DISTINCT name, type FROM dependencies dependencies
| summarize by name, type		 總結
不同
-- SELECT name, COUNT(DISTINCT type)
FROM dependencies
GROUP BY name		 dependencies
| summarize by name, type | summarize count() by name
// or approximate for large sets
dependencies
| summarize dcount(type) by name 		count ()
dcount ()
資料行別名、擴充 SELECT operationName as Name, AVG(duration) as AvgD FROM dependencies
GROUP BY name		 dependencies
| summarize AvgD = avg(duration) by Name=operationName		 Alias 陳述式
-- SELECT conference, CONCAT(sessionid, ' ' , session_title) AS session FROM ConferenceSessions ConferenceSessions
| extend session=strcat(sessionid, " ", session_title)
| project conference, session		 strcat ()
專案
排序 SELECT name, timestamp FROM dependencies
ORDER BY timestamp ASC		 dependencies
| project name, timestamp
| sort by timestamp asc nulls last		 sort
依量值的前 n 個 SELECT TOP 100 name, COUNT(*) as Count FROM dependencies
GROUP BY name
ORDER BY Count DESC		 dependencies
| summarize Count = count() by name
| top 100 by Count desc		 top
聯集 SELECT * FROM dependencies
UNION
SELECT * FROM exceptions		 union dependencies, exceptions union
-- SELECT * FROM dependencies
WHERE timestamp > ...
UNION
SELECT * FROM exceptions
WHERE timestamp > ...		 dependencies
| where timestamp > ago(1d)
| union
(exceptions
| where timestamp > ago(1d))
Join SELECT * FROM dependencies
LEFT OUTER JOIN exceptions
ON dependencies.operation_Id = exceptions.operation_Id		 dependencies
| join kind = leftouter
(exceptions)
on $left.operation_Id == $right.operation_Id		 join
巢狀查詢 SELECT * FROM dependencies
WHERE resultCode ==
(SELECT TOP 1 resultCode FROM dependencies
WHERE resultId = 7
ORDER BY timestamp DESC)		 dependencies
| where resultCode == toscalar(
dependencies
| where resultId == 7
| top 1 by timestamp desc
| project resultCode)		 toscalar
Having SELECT COUNT(\*) FROM dependencies
GROUP BY name
HAVING COUNT(\*) > 3		 dependencies
| summarize Count = count() by name
| where Count > 3		 總結
where

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