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  • Incrementing the version number of the data file
  • Multi-file queries
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Stored procedures
Allows you to find out:
  • whether the content of a data file was modified.
  • whether the content of a data file used by a query was modified.
This function is used to detect the modifications made to a data file shared among several programs. If a modification is detected, you have the ability to refresh the data displayed in the window or in the page.
Example
VerNum = HVersion(Customer)
// First evaluation of the data file version
VerNum is int
VerNum = HVersion(Customer)
// Processes
// Second evaluation of the data file version
IF VerNum <> HVersion(Customer) THEN
Info("The Customer data file was modified.")
END
Syntax
<Result> = HVersion([<Data file or query>])
<Result>: Integer
Version number of the data file.
OLE DBNative Connectors (Native Accesses) The version number is always equal to 0.
<Data file or query>: Optional character string
  • Name of the data file used.
  • Name of the query used.
  • If this parameter is not specified, HVersion will handle the last data file (last query) used.
Java The data file used must be an HFSQL data file. Otherwise, the version number is always equal to 0.
Remarks

Incrementing the version number of the data file

When creating the data file, the version number is initialized to 1. This number is incremented whenever the file content is modified (HAdd, HWrite, HModify, TableSave, TableDelete, HFree, HDelete, HCross). The number is incremented if the function is successful.
Remark: HVersion can be used on indexed or non-indexed data files.

Multi-file queries

In the case of a multi-file query, HVersion returns the sum of the HVersion of all data files used in the query.
Component: wd290hf.dll
Minimum version required
  • Version 9
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Last update: 05/26/2022

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