<Source>.DataSourceKnown (Function)

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How to initialize a Data Source variable

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<Source>.DataSourceKnown (Function)

In french: <Source>.SourceDeDonnéesConnue

Determines if a data source has been initialized. This function prevents errors such as "You called XXX . The YYY data source has not been initialized".

Difference with function <Source>.QueryExecuted function: The <Source>.DataSourceKnown FUNCTION function determines whether the data source is known to the HFSQL engine, regardless of its content. <Source>.QueryExecuted can only be used with queries.

Example

MaVue is Data Source
// MaVue est associée à une vue

IF MaVue.DataSourceKnown() = False THEN
	// Initialisation de la variable MaVue 
	MaVue.CreateView(CLIENT, "*", "NOM,VILLE", "NOM]='A'", hViewDefault)
END

Syntax

<Result> = <Data source to check>.DataSourceKnown()

<Result>: Boolean

True if the data source has been initialized,
False otherwise. HErrorInfo returns more details about the problem.

<Data source to check>: Data Source variable

Data Source variable to be checked. This data source can correspond to:
an external data file,
an SQL query,
a view.

Remarks

How to initialize a Data Source variable

The initialization of a Data Source variable depends on its content:

External data file: use function <Source>.DeclareExternal.
SQL queries and requests: use functions <Source>.ExecuteQuery, <Source>.ExecuteSQLQuery, etc.
HFSQL view: use function <Source>.CreateView.

For more details, see the help page on the Data Source variable type.

Business / UI classification: Business Logic

Component: wd300hf.dll