Physical data file associated with an alias

Canceling the aliases of one or more data files

Alias and queries

• If the query was created through programming (<Source>.ExecuteSQLQuery), all you have to do is create the alias query with this same function while specifying the alias name.
• If the query was created by the report editor, to create an alias, you must:
  • run the initial query.
  • use <Source>.Alias and specify the query name as well as the alias name.
  • use <Source>.ExecuteQuery with the alias query. The alias is initialized.
  For example:
  

  AliasRequête is Data Source
  REQ_Requête1.Alias(AliasRequête)
  AliasRequête.ExecuteQuery()

  
  Note When creating the alias, the initial query must have been executed.
  Example:
  

  AliasRequête is Data Source 
  IF REQ_Requête1.ExécuteRequête() = False THEN
  	Error(HError(hErrCurrent)) 
  ELSE
  	REQ_Requête1.LitPremier()
  	Trace(REQ_Requête1.Ville)
  	REQ_Requête1.Alias(AliasRequête)
  	IF AliasRequête.ExecuteQuery() = False THEN
  		Error(HError(hErrCurrent)) 
  	ELSE
  		FOR EACH AliasRequête
  			Trace(AliasRequête.Ville)
  		END
  	END
  END

Handling the alias file and its items

• To avoid the "Unknown identifier" error when using an alias file and its items, it is recommended to use a Data source variable to declare the name of the alias before using <Source>.Alias.
  For example:
  

  Commande2018 is Data Source
  Commande.Alias(Commande2018)

  
  Warning: use of the keyword External keyword is possible, but causes a significant slowdown at runtime.
• In functions <Source>.ReadSeek, <Source>.ReadFirst, <Source>.ReadNext, ... the alias field name cannot be used directly: the field name must be enclosed in quotation marks.
  For example:
  

  srcAlias.ReadSeekFirst("RubriqueClé", "Valeur Recherchée")

• The name of the data source must not be used in quotation marks, if Automatic naming of data sources is enabled in the project description window.
• In the window or page editor, controls cannot be directly bound to the items of the alias files. You must:
  • assign a value to each control in the code.
  • use the ControlAlias function or the DataBinding property before calling:
    • the <Window>.FromFile function.
    • the <Page>.FromFile function.
  Example:
  

  ControlAlias(Champ, srcAlias)
  OR
   ControlAlias(GR_GroupeDeChamp, srcAlias)
  OR
   ControlAlias(FEN_Fenêtre, srcAlias)
  OR
   SAI_NomClient.LiaisonFichier = "SrcAlias.NomClient"

• The alias files can be handled by <Source>.ListItem and <Source>.ListKey. The alias files can be re-indexed.
• By default, the password of an alias file is identical to the password of the initial data file. This password can be changed using <Source>.Password. The name of the data file used in this function corresponds to the name of the alias.
• The automatic modification of the data files can be applied to the alias files.
• The locks performed on the data files or on the records are effective between the aliases of the same instance of an application.