SQL to Kusto cheat sheet
If you're familiar with SQL and want to learn KQL, you can use Azure Data Explorer to translate SQL queries into KQL.
To translate an SQL query, preface the SQL query with a comment line, --
, and the keyword explain
. The output will show the KQL version of the query, which can help you understand the KQL syntax and concepts.
--
explain
SELECT COUNT_BIG(*) as C FROM StormEvents
Output
Query |
---|
StormEvents | summarize C=count() | project C |
SQL to Kusto cheat sheet
The table below shows sample queries in SQL and their KQL equivalents.
Category | SQL Query | Kusto Query |
---|---|---|
Select data from table | SELECT * FROM dependencies |
dependencies |
-- | SELECT name, resultCode FROM dependencies |
dependencies | project name, resultCode |
-- | SELECT TOP 100 * FROM dependencies |
dependencies | take 100 |
Null evaluation | SELECT * FROM dependencies |
dependencies |
Comparison operators (date) | SELECT * FROM dependencies |
dependencies |
-- | SELECT * FROM dependencies |
dependencies |
Comparison operators (string) | SELECT * FROM dependencies |
dependencies |
-- | -- substring |
// substring |
-- | -- wildcard |
// wildcard |
Comparison (boolean) | SELECT * FROM dependencies |
dependencies |
Grouping, Aggregation | SELECT name, AVG(duration) FROM dependencies |
dependencies |
Distinct | SELECT DISTINCT name, type FROM dependencies |
dependencies |
-- | SELECT name, COUNT(DISTINCT type) |
dependencies |
Column aliases, Extending | SELECT operationName as Name, AVG(duration) as AvgD FROM dependencies |
dependencies |
-- | SELECT conference, CONCAT(sessionid, ' ' , session_title) AS session FROM ConferenceSessions |
ConferenceSessions |
Ordering | SELECT name, timestamp FROM dependencies |
dependencies |
Top n by measure | SELECT TOP 100 name, COUNT(*) as Count FROM dependencies |
dependencies |
Union | SELECT * FROM dependencies |
union dependencies, exceptions |
-- | SELECT * FROM dependencies |
dependencies |
Join | SELECT * FROM dependencies |
dependencies |
Nested queries | SELECT * FROM dependencies |
dependencies |
Having | SELECT COUNT(*) FROM dependencies |
dependencies |
Next steps
- Use T-SQL to query data