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!startswith operator

Applies to: ✅ Microsoft FabricAzure Data ExplorerAzure MonitorMicrosoft Sentinel

Filters a record set for data that doesn't start with a case-insensitive search string.

The following table compares the startswith operators using the abbreviations provided:

  • RHS = right-hand side of the expression
  • LHS = left-hand side of the expression
Operator Description Case-Sensitive Example (yields true)
startswith RHS is an initial subsequence of LHS No "Fabrikam" startswith "fab"
!startswith RHS isn't an initial subsequence of LHS No "Fabrikam" !startswith "kam"
startswith_cs RHS is an initial subsequence of LHS Yes "Fabrikam" startswith_cs "Fab"
!startswith_cs RHS isn't an initial subsequence of LHS Yes "Fabrikam" !startswith_cs "fab"

For more information about other operators and to determine which operator is most appropriate for your query, see datatype string operators.

Performance tips

Note

Performance depends on the type of search and the structure of the data. For best practices, see Query best practices.

When possible, use the case-sensitive !startswith_cs.

Syntax

T | where column !startswith (expression)

Learn more about syntax conventions.

Parameters

Name Type Required Description
T string ✔️ The tabular input whose records are to be filtered.
column string ✔️ The column by which to filter.
expression scalar ✔️ The scalar or literal expression for which to search.

Returns

Rows in T for which the predicate is true.

Example

StormEvents
| summarize event_count=count() by State
| where State !startswith "i"
| where event_count > 2000
| project State, event_count

Output

State event_count
TEXAS 4701
KANSAS 3166
MISSOURI 2016