getschema operator in APL returns the schema of a dataset, including field names and their data types. You can use it to inspect the structure of a dataset before performing queries or transformations. This operator is useful when exploring new datasets, verifying data consistency, or debugging queries.
For users of other query languages
If you come from other query languages, this section explains how to adjust your existing queries to achieve the same results in APL.Splunk SPL users
Splunk SPL users
In Splunk SPL, you can use the
fieldsummary command to get schema-related information about a dataset. However, getschema in APL is more direct and focused specifically on returning field names and types without additional summary statistics.ANSI SQL users
ANSI SQL users
In ANSI SQL, retrieving schema information is typically done using
INFORMATION_SCHEMA queries. APL’s getschema operator provides a more straightforward way to get schema details without requiring system views.Usage
Syntax
Parameters
Thegetschema operator doesn’t take any parameters.
Returns
| Field | Type | Description |
|---|---|---|
| ColumnName | string | The name of the field in the dataset. |
| ColumnOrdinal | number | The index number of the field in the dataset. |
| ColumnType | string | The data type of the field. |
| DataType | string | The APL-internal name for the data type of the field. |
Use case example
You can usegetschema to explore the schema of your log data before running queries.
Query
| ColumnName | DataType | ColumnOrdinal | ColumnType |
|---|---|---|---|
| _sysTime | datetime | 0 | datetime |
| _time | datetime | 1 | datetime |
| content_type | string | 2 | string |
| geo.city | string | 3 | string |
| geo.country | string | 4 | string |
| id | string | 5 | string |
List of related operators
- project: Use
projectto select specific fields instead of retrieving the entire schema. - extend: Use
extendto add new computed fields to your dataset after understanding the schema. - summarize: Use
summarizefor aggregations once you verify field types usinggetschema. - where: Use
whereto filter datasets based on field values after checking their schema. - order: Use
order byto sort datasets after verifying schema details.