- The query
object model contains classes to define and run a query. These
objects are used to define the query data source.
2.
System class
a.
QueryRun : Executes the query and fetches the data.
b.
Query
:The top level of the query definition. This class holds some properties itself
and has one or more related data sources.
c.
QueryBuildDataSource :Defines access to a
single data source in the query. If more than one data source exists at the
same level in a query, they result in separate SQL statements that are executed
sequentially. If one data source exists as a child of another data source, a
join is created between the two data sources.
d.
QueryBuildFieldList : Defines which fields are
returned from the database. The default is that the field list is dynamic,
which returns all fields from the data source table, map, or view. Each data
source has only one QueryBuildFieldList object, which contains information on all selected fields. It's
possible to specify aggregate functions like SUM, COUNT, and AVG on the field list object.
e.
QueryBuildRange : Defines a subset of records
returned based on a single field. A range is translated into a WHERE clause in the query SQL statement. If more than one field is used to
limit the query (WHERE clause), the data source will contain more than one range.
f.
QueryBuildDynalink : Contains information
regarding a relation (limitation) to an external record. When the query is run,
this information is converted to additional entries in the WHERE clause of the query SQL statement. Can only exist on the parent data
source of a query. The function is used by forms, when two data sources are
synchronized. Then the child data source will contain a dynalink or dynalinks
to the parent data source. The function is used even if the two data sources
are placed in two different forms but are still synchronized.
g.
QueryBuildLink : Specifies the relation
between the two data sources in the join. Can only exist on a child data
source.
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