serialize operator

Applies to: ✅ Microsoft Fabric ✅ Azure Data Explorer ✅ Azure Monitor ✅ Microsoft Sentinel

Marks that the order of the input row set is safe to use for window functions.

The operator has a declarative meaning. It marks the input row set as serialized (ordered), so that window functions can be applied to it.

Syntax

serialize [Name1 = Expr1 [, Name2 = Expr2]...]

Learn more about syntax conventions.

Parameters

Name	Type	Required	Description
Name	string		The name of the column to add or update. If omitted, the output column name is automatically generated.
Expr	string	✔️	The calculation to perform over the input.

Examples

Serialize subset of rows by condition

Run the query

TraceLogs
| where ClientRequestId == "5a848f70-9996-eb17-15ed-21b8eb94bf0e"
| serialize

Add row number to the serialized table

To add a row number to the serialized table, use the row_number() function.

Run the query

TraceLogs
| where ClientRequestId == "5a848f70-9996-eb17-15ed-21b8eb94bf0e"
| serialize rn = row_number()

Serialization behavior of operators

The output row set of the following operators is marked as serialized.

• getschema
• range
• sort
• top
• top-hitters

The output row set of the following operators is marked as nonserialized.

• count
• distinct
• evaluate
• facet
• join
• make-series
• mv-expand
• reduce by
• sample
• sample-distinct
• summarize
• top-nested

All other operators preserve the serialization property. If the input row set is serialized, then the output row set is also serialized.