SQL para Linguagem de Pesquisa Kusto folha de truques
Se estiver familiarizado com o SQL e quiser aprender KQL, transfira consultas SQL para KQL ao pré-configurar a consulta SQL com uma linha de comentários e --
a palavra-chave explain
. O resultado mostra a versão KQL da consulta, que pode ajudá-lo a compreender a sintaxe e os conceitos do KQL.
--
explain
SELECT COUNT_BIG(*) as C FROM StormEvents
Saída
Consulta |
---|
StormEvents<br> | summarize C=count()<br> | project C |
Truques e dicas do SQL para Kusto
A tabela seguinte mostra as consultas de exemplo no SQL e os respetivos equivalentes de KQL.
Categoria | Consulta SQL | Consulta Kusto | Saber mais |
---|---|---|---|
Selecionar dados da tabela | SELECT * FROM dependencies |
dependencies |
Instruções de expressão tabular |
-- | SELECT name, resultCode FROM dependencies |
dependencies | project name, resultCode |
projeto |
-- | SELECT TOP 100 * FROM dependencies |
dependencies | take 100 |
take |
Avaliação nula | SELECT * FROM dependencies WHERE resultCode IS NOT NULL |
dependencies | where isnotnull(resultCode) |
isnotnull() |
Operadores de comparação (data) | 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)) |
entre |
Operadores de comparação (cadeia) | SELECT * FROM dependencies WHERE type = "Azure blob" |
dependencies | where type == "Azure blob" |
Operadores lógicos |
-- | -- substring SELECT * FROM dependencies WHERE type like "%blob%" |
// substring dependencies | where type has "blob" |
tem |
-- | -- wildcard SELECT * FROM dependencies WHERE type like "Azure%" |
// wildcard dependencies | where type startswith "Azure" // or dependencies | where type matches regex "^Azure.*" |
startswith corresponde ao regex |
Comparação (booleana) | SELECT * FROM dependencies WHERE !(success) |
dependencies | where success == False |
Operadores lógicos |
Agrupamento, Agregação | SELECT name, AVG(duration) FROM dependencies GROUP BY name |
dependencies | summarize avg(duration) by name |
resumir avg() |
Distinct | SELECT DISTINCT name, type FROM dependencies |
dependencies | summarize by name, type |
resumir distinct |
-- | 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() |
Aliases de coluna, Expandir | SELECT operationName as Name, AVG(duration) as AvgD FROM dependencies GROUP BY name |
dependencies | summarize AvgD = avg(duration) by Name=operationName |
Instrução alias |
-- | SELECT conference, CONCAT(sessionid, ' ' , session_title) AS session FROM ConferenceSessions |
ConferenceSessions | extend session=strcat(sessionid, " ", session_title) | project conference, session |
strcat() projeto |
Ordenação | SELECT name, timestamp FROM dependencies ORDER BY timestamp ASC |
dependencies | project name, timestamp | sort by timestamp asc nulls last |
ordenar |
N superior por medida | 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 |
União | SELECT * FROM dependencies UNION SELECT * FROM exceptions |
union dependencies, exceptions |
união |
-- | SELECT * FROM dependencies WHERE timestamp > ... UNION SELECT * FROM exceptions WHERE timestamp > ... |
dependencies | where timestamp > ago(1d) | union (exceptions | where timestamp > ago(1d)) |
|
Participar | 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 |
associar |
Consultas aninhadas | 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 |
Ter | SELECT COUNT(\*) FROM dependencies GROUP BY name HAVING COUNT(\*) > 3 |
dependencies | summarize Count = count() by name | where Count > 3 |
resumir em que |
Conteúdo relacionado
- Utilizar o T-SQL para consultar dados
Comentários
https://aka.ms/ContentUserFeedback.
Brevemente: Ao longo de 2024, vamos descontinuar progressivamente o GitHub Issues como mecanismo de feedback para conteúdos e substituí-lo por um novo sistema de feedback. Para obter mais informações, veja:Submeter e ver comentários