KQL quick reference
Applies to: ✅ Microsoft Fabric ✅ Azure Data Explorer ✅ Azure Monitor ✅ Microsoft Sentinel
This article shows you a list of functions and their descriptions to help get you started using Kusto Query Language.
| Operator/Function | Description | Syntax |
|---|---|---|
| Filter/Search/Condition | Find relevant data by filtering or searching | |
| where | Filters on a specific predicate | T | where Predicate |
| where contains/has | Contains: Looks for any substring match Has: Looks for a specific word (better performance) |
T | where col1 contains/has "[search term]" |
| search | Searches all columns in the table for the value | [TabularSource |] search [kind=CaseSensitivity] [in (TableSources)] SearchPredicate |
| take | Returns the specified number of records. Use to test a query Note: take and limit are synonyms. |
T | take NumberOfRows |
| case | Adds a condition statement, similar to if/then/elseif in other systems. | case(predicate_1, then_1, predicate_2, then_2, predicate_3, then_3, else) |
| distinct | Produces a table with the distinct combination of the provided columns of the input table | distinct [ColumnName], [ColumnName] |
| Date/Time | Operations that use date and time functions | |
| ago | Returns the time offset relative to the time the query executes. For example, ago(1h) is one hour before the current clock's reading. |
ago(a_timespan) |
| format_datetime | Returns data in various date formats. | format_datetime(datetime , format) |
| bin | Rounds all values in a timeframe and groups them | bin(value,roundTo) |
| Create/Remove Columns | Add or remove columns in a table | |
| Outputs a single row with one or more scalar expressions | print [ColumnName =] ScalarExpression [',' ...] |
|
| project | Selects the columns to include in the order specified | T | project ColumnName [= Expression] [, ...] Or T | project [ColumnName | (ColumnName[,]) =] Expression [, ...] |
| project-away | Selects the columns to exclude from the output | T | project-away ColumnNameOrPattern [, ...] |
| project-keep | Selects the columns to keep in the output | T | project-keep ColumnNameOrPattern [, ...] |
| project-rename | Renames columns in the result output | T | project-rename new_column_name = column_name |
| project-reorder | Reorders columns in the result output | T | project-reorder Col2, Col1, Col* asc |
| extend | Creates a calculated column and adds it to the result set | T | extend [ColumnName | (ColumnName[, ...]) =] Expression [, ...] |
| Sort and Aggregate Dataset | Restructure the data by sorting or grouping them in meaningful ways | |
| sort operator | Sort the rows of the input table by one or more columns in ascending or descending order | T | sort by expression1 [asc|desc], expression2 [asc|desc], … |
| top | Returns the first N rows of the dataset when the dataset is sorted using by |
T | top numberOfRows by expression [asc|desc] [nulls first|last] |
| summarize | Groups the rows according to the by group columns, and calculates aggregations over each group |
T | summarize [[Column =] Aggregation [, ...]] [by [Column =] GroupExpression [, ...]] |
| count | Counts records in the input table (for example, T) This operator is shorthand for summarize count() |
T | count |
| join | Merges the rows of two tables to form a new table by matching values of the specified column(s) from each table. Supports a full range of join types: fullouter, inner, innerunique, leftanti, leftantisemi, leftouter, leftsemi, rightanti, rightantisemi, rightouter, rightsemi |
LeftTable | join [JoinParameters] ( RightTable ) on Attributes |
| union | Takes two or more tables and returns all their rows | [T1] | union [T2], [T3], … |
| range | Generates a table with an arithmetic series of values | range columnName from start to stop step step |
| Format Data | Restructure the data to output in a useful way | |
| lookup | Extends the columns of a fact table with values looked-up in a dimension table | T1 | lookup [kind = (leftouter|inner)] ( T2 ) on Attributes |
| mv-expand | Turns dynamic arrays into rows (multi-value expansion) | T | mv-expand Column |
| parse | Evaluates a string expression and parses its value into one or more calculated columns. Use for structuring unstructured data. | T | parse [kind=regex [flags=regex_flags] |simple|relaxed] Expression with * (StringConstant ColumnName [: ColumnType]) *... |
| make-series | Creates series of specified aggregated values along a specified axis | T | make-series [MakeSeriesParamters] [Column =] Aggregation [default = DefaultValue] [, ...] on AxisColumn from start to end step step [by [Column =] GroupExpression [, ...]] |
| let | Binds a name to expressions that can refer to its bound value. Values can be lambda expressions to create query-defined functions as part of the query. Use let to create expressions over tables whose results look like a new table. |
let Name = ScalarExpression | TabularExpression | FunctionDefinitionExpression |
| General | Miscellaneous operations and function | |
| invoke | Runs the function on the table that it receives as input. | T | invoke function([param1, param2]) |
| evaluate pluginName | Evaluates query language extensions (plugins) | [T |] evaluate [ evaluateParameters ] PluginName ( [PluginArg1 [, PluginArg2]... ) |
| Visualization | Operations that display the data in a graphical format | |
| render | Renders results as a graphical output | T | render Visualization [with (PropertyName = PropertyValue [, ...] )] |