!hasprefix_cs operator
Filters a record set for data that doesn't have a case-sensitive starting string. !hasprefix_cs searches for indexed terms, where an indexed term is three or more characters. If your term is fewer than three characters, the query scans the values in the column, which is slower than looking up the term in the term index.
| Operator | Description | Case-Sensitive | Example (yields true) |
|---|---|---|---|
hasprefix |
RHS is a term prefix in LHS | No | "North America" hasprefix "ame" |
!hasprefix |
RHS isn't a term prefix in LHS | No | "North America" !hasprefix "mer" |
hasprefix_cs |
RHS is a term prefix in LHS | Yes | "North America" hasprefix_cs "Ame" |
!hasprefix_cs |
RHS isn't a term prefix in LHS | Yes | "North America" !hasprefix_cs "CA" |
Note
The following abbreviations are used in the above table:
- RHS = right hand side of the expression
- LHS = left hand side of the expression
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.
Syntax
T | where column !hasprefix_cs (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 !hasprefix_cs "P"
| count
Output
| Count |
|---|
| 64 |