TfrxADOQuery

This component executes SQL queries on a DB. It has the following properties:

Property	Description
DatabaseName	connection name (name of the TfrxADODatabase component)
FieldAliases	enables aliases to be set for the dataset fields
Filter	expression for filtering records
Filtered	whether filtered or not
Master	master dataset
Params	list of query parameters
SQL	Query text
UserName	alias for the dataset, used in code
IgnoreDupParams	when True allows parameters with duplicate names. The name of the Query parameters will not be edited in the parameter editor

The Active, DatabaseName, FieldAliases, Filter, Filtered and Master properties are similar to those of the TfrxADOTable component described above. The SQL property has its own editor for entering the SQL query.

The Params property also has its own editor. It is enabled when a Query text contains parameters.

A parameter can be one of two types: its value either derived from the master-source or set as a discrete value (either an absolute value, as shown above, or linked to a variable or to an object property).

When a parameter is derived from the data master-set the TfrxADOQuery.Master property has to be set. This dataset must contain a field of the same name as the parameter. Neither the parameter type nor its value has to be specified.