2.1.4 Queries
An AXL Query defines a way to build a view on list data to be used as the data source for a Form, Report, ComboBox, or ListBox. Queries in AXL are a subset of the functionality defined by the SELECT statement in Transact-SQL [MSDN-TSQL-Ref].
An AXL Query can be used to filter or order data. It can also be used to bring together data from more than one input source, including another AXL Query, to form a joint data source. Queries can take input from non-List sources in the form of parameters, which can be included in the output columns (1) as part of an expression or used to filter the query results. Queries can use expressions in output columns or restrictions to perform calculations or formatting on data.
AXL Queries include components that map to the following clauses of a SELECT statement as expressed by Transact-SQL [MSDN-TSQL-Ref]. Restrictions on what is permitted for each AXL Query component are described in the linked sections in this document.
|
Transact-SQL clause |
Query AXL |
|---|---|
|
SELECT |
Results and Parameters |
|
FROM |
References and Joins |
|
WHERE |
Restriction child element of CT_Query |
|
ORDER BY |