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  • Multiple changes of directory
  • Changing the name of data file
  • Substituting directories
  • Miscellaneous
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Stored procedures
  • Modifies the access path to a data file (which means the directory where the data file will be used). If the data file is opened when using HChangeDir, the data file is automatically closed.
    Reminder: By default, the physical file corresponding to the data file described in the analysis is handled in the directory specified in the analysis.
  • Changes the name of database associated with a table. In this case, the database name specified in the connection properties of table (in the data model editor) is ignored.
    To modify the connection parameters of a data file not in HFSQL format, we recommend that you use HDescribeConnection and HChangeConnection.
Example
Reports and QueriesHFSQL ClassicHyper File 5.5
// Create the HFSQL Classic Stat data file in
// "C:\Statistics\January"
HChangeDir(Stat, "C:\Statistics\January")
HCréation(Stat)
Reports and QueriesHFSQL Client/Server
// Create the HFSQL Client/Server Stat data file in "\January\"
// This directory is at the root
// of database folder (HFSQL Client/Server connection)
HChangeDir(Stat, ".\January\")
Reports and QueriesOLE DBNative Connectors (Native Accesses)
// Data file associated with a connection by OLE DB.
// Replace the database that will be used for the "Customers" table
HChangeDir(Customers, "C:\Temp\MyTestDB.mdb")
HCréation(Customers)
// The "Customers" table was created in the "c:\temp\mytestdb.mdb" database
// The "Customers" table of database ("c:\temp\myinitialdb.mdb") was not modified
Syntax

With HFSQL data files Hide the details

<Result> = HChangeDir(<Data file> , <New data file path>)
<Result>: Boolean
  • True if the operation was performed,
  • False if a problem occurs. HError is used to identify the error.
<Data file>: Character string
Logical name of HFSQL data file (defined in the analysis).
If this parameter is equal to "*", the change of directory will be applied to all known data files (described in the analysis).
This parameter can also correspond to the name of a group of files (or custom-folder) defined in the analysis (not available in Android and Android widget).
<New data file path>: Character string
New access path to the data file (up to 260 characters). This path can contain the name of drive and directories, or it can be a relative path.
If the path is a relative path, the "." (or "?") character is used to specify the current directory and the ".." character is used to specify the parent directory.
If this parameter corresponds to an empty string (""), the data file will be handled in the directory specified in the analysis.
HFSQL Client/Server The access path to the data file must be relative to the database found on the server. You cannot specify a path outside the database. A WLanguage error occurs when attempting to access data files outside the database. For example:
Valid path:
HChangeDir(FileName, "SUBDIR")
 
OR
 
HChangeDir(FileName, ".\SUBDIR")

Invalid path:
HChangeDir(FileName, "C:\DB\SUBDIR")

The new path will be automatically created if it is valid and if it does not exist.
Reports and QueriesOLE DBNative Connectors (Native Accesses)

With an OLE DB access or a Native Connector (also called Native Access) Hide the details

<Result> = HChangeDir(<Data file> , <New database>)
<Result>: Boolean
  • True if the operation was performed,
  • False if a problem occurs. HError is used to identify the error.
<Data file>: Character string
Logical name of table (defined in the analysis).
If this parameter is equal to "*", HChangeDir is ignored.
Caution: If this parameter is equal to "*" and if one of the data files found in the analysis was associated with a connection (HChangeConnection) before the call to HChangeDir, the directory modification will be taken into account for this data file when closing the connection.
<New database>: Character string
Access path to database to use (up to 260 characters). In this case, the database name specified in the connection properties of table in the analysis is ignored.
This path can contain the name of drive and directories, or it can be a relative path.
If the path is a relative path, the "." (or "?") character is used to specify the current directory and the ".." character is used to specify the parent directory.
Remarks

Multiple changes of directory

HChangeDir can be called several times with different parameters. When the path is redefined several times for the same data file, the last specified path replaces all the other ones.

Changing the name of data file

HChangeDir can only be used to change the access path to the physical data file. To change the physical name of the data file, use HChangeName.

Substituting directories

HChangeDir is used to associate a directory with a data file. To replace a directory with another one, use HSubstDir.
Caution: The directory substitution made by HSubstDir applies to the directory defined by HChangeDir. For example:
HSubstDir("C:\Statistics\January", "C:\New\JanStats")
HChangeDir(Stat, "C:\Statistics\January")
HCréation(Stat) // Data file created in C:\New\JanStats

Miscellaneous

  • If the ".REP" file is used (HSetREP), the new path is saved to the ".REP" file (see management of .REP files).
  • Closing the data file stores the new path but does not store a possible password specified when opening the data file.
  • HChangeDir is equivalent to HAssign, available in earlier versions.
  • This function can be used when establishing a connection with an HFSQL server.  Caution: The order in which the functions for connecting to an HFSQL Client/Server database are called is important. For more details, see Optimizing the connection times to the HFSQL Client/Server databases.
  • Native Connectors (Native Accesses) HChangeDir can be used with the Native XML Connector.
Component: wd290hf.dll
Minimum version required
  • Version 9
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Last update: 02/01/2024

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