MarkLogic 12 EA 1 Product Documentationop:select
op:select( $plan as map:map, $columns as columnIdentifier*, [$qualifier as xs:string?] ) as map:map
Summary
This call projects the specified columns from the current row set and / or applies a qualifier to the columns in the row set. Unlike SQL, a select call is not required in an Optic query.
| Parameters | |
|---|---|
| $plan | The Optic Plan. You can either use the XQuery => chaining operator or specify the variable that captures the return value from the previous operation. |
| $columns | The columns to project from the input rows. The columns can be named with a string or a column parameter function such as op:col or constructed from an expression with op:as. |
| $qualifier | Specifies a name for qualifying the column names in place of the combination of the schema and view names. Use cases for the qualifier include self joins. Using an empty string removes all qualification from the column names. |
See Also
-
- op:as function
- op:bind-as function
Example
xquery version "1.0-ml";
import module namespace op="http://marklogic.com/optic"
at "/MarkLogic/optic.xqy";
op:from-view("main", "employees")
=> op:select(("EmployeeID", "FirstName", "LastName"))
=> op:order-by("EmployeeID")
=> op:result()