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  • Use conditions
  • Automatic reindexing
  • "Zero-downtime" reindexing
  • Calculation of statistics
  • Directory of temporary files
  • Managing non-Latin character sets
  • Access rights to the data file
  • Special case: Files corrupted after a computer reboot or a fatal error
  • Previous versions
WINDEV
WindowsLinuxUniversal Windows 10 AppJavaReports and QueriesUser code (UMC)
WEBDEV
WindowsLinuxPHPWEBDEV - Browser code
WINDEV Mobile
AndroidAndroid Widget iPhone/iPadIOS WidgetApple WatchMac CatalystUniversal Windows 10 App
Others
Stored procedures
Rebuilds the file index (".NDX" file). You also have the ability to reindex full-text indexes (".FTX" extension). A data file can be reindexed even when it is accessed by applications. For more details, see the remarks.
Reminder: The reindex operation reorganizes the indexes. After the reindex operation, the access to indexes is optimized. Reindexing a data file can become necessary further to the loss or modification of the index file. The HCheckIndex function is used to regularly check the report of the index file.
Versions 17 and later
iPhone/iPad This function is now available for iPhone/iPad applications.
New in version 17
iPhone/iPad This function is now available for iPhone/iPad applications.
iPhone/iPad This function is now available for iPhone/iPad applications.
Remark: From version 19, HFSQL is the new name of HyperFileSQL.
Versions 19 and later
Android This function is now available for Android applications using data files in HFSQL format.
Android Widget This function is now available in Android widget mode.
Java This function is now available for Java applications.
New in version 19
Android This function is now available for Android applications using data files in HFSQL format.
Android Widget This function is now available in Android widget mode.
Java This function is now available for Java applications.
Android This function is now available for Android applications using data files in HFSQL format.
Android Widget This function is now available in Android widget mode.
Java This function is now available for Java applications.
Versions 21 and later
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.
WINDEVWEBDEV - Server code This function is now available to reindex the data files of an HFSQL cluster.
New in version 21
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.
WINDEVWEBDEV - Server code This function is now available to reindex the data files of an HFSQL cluster.
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.
WINDEVWEBDEV - Server code This function is now available to reindex the data files of an HFSQL cluster.
IF HIndex(UnFichier, hNdxNormal) = True THEN
TableDisplay(TABLE_MaTable, taStart)
END
Syntax
<Result> = HIndex([<Data file> [, <Mode> [, <eye> [, <Density rate>]]]])
<Result>: Boolean
  • True if the reindex operation was successfully performed,
  • False otherwise. HError returns more details about the problem.
<Data file>: Optional character string
Name of the data file used.
If this name is not specified, HIndex will use the last data file used by the last HFSQL management function (function starting with "H").
<Mode>: Optional Integer constant (or combination of constants)
Configure the reindex operation:
hChangeCharsetReindexing with change of character set.
The new alphabet defined with the ChangeCharset function will be taken into account during the re-indexation. The sorts, the searches, ... on string keys (strings, characters, date and time) will be performed according to this character set.
hFTXReindexing full-text indexes.
Versions 20 and later
hMmoCompact
New in version 20
hMmoCompact
hMmoCompact
Compacting and defragmentation of "Mmo" files.

Caution: This constant cannot be combined with the constants hNdxCompaction, hMemoVerify, hFTX, hNdxNormal or hNdxDelete.
hNdxCompactReindexing with compression (keeps the active records only. All the other records are permanently deleted).
hNdxMinimalReindexing while taking the corrupted keys into account only. This parameter is ignored if the hNdxDelete or hNdxCompact constant is enabled.
hNdxSilentReindexing without display
hNdxNormal
(default value)
Standard reindexing (with statistics and without compression).
The statistics are used to optimize the queries and the filters (see the Notes). The calculation of the statistics takes into account only the active records.
hNdxNoStatRe-indexation without calculation of statistics. This constant increases the available space by reducing the size of index files.
Caution: The statistics are very important to get correct execution times when using queries, filters with condition and views with condition.
hNdxDeleteRe-indexation with deletion of damaged records
Versions 15 and later
hBackgroundTask
New in version 15
hBackgroundTask
hBackgroundTask
HFSQL Client/Server Reindexing performed in background task. The applications are not locked during the reindex operation.
This feature is available in Client/Server mode only.
hCheckMemoStandard reindexing with memo check and correction if necessary (used to retrieve the damaged memos).
Versions 23 and later
WINDEVWEBDEV - Server code Remark: Before reindexing memos, you have the ability to check the status of memos via HCheckMemo.
New in version 23
WINDEVWEBDEV - Server code Remark: Before reindexing memos, you have the ability to check the status of memos via HCheckMemo.
WINDEVWEBDEV - Server code Remark: Before reindexing memos, you have the ability to check the status of memos via HCheckMemo.
<eye>: Optional control or window name or optional integer
  • Name of window where the progress bar will be displayed,
  • Name of the Progress Bar control that displays the reindexing progress,
  • Identifier (Handle) of window that displays the progress bar.
WEBDEV - Server code This parameter is ignored.
<Density rate>: Integer included between 1 and 100
Density rate of indexes. This rate is set to 60 by default.
The higher this rate is, the denser and smaller the index is. In this case, the browses, searches, filters and queries will be faster. The additions of records and the modifications of records may be slower.
The smallest this rate is, the less dense and the bigger the index will be. In this case, the browses, searches, filters and queries will be slower. The additions of records and the modifications of records will be faster.
Caution: this parameter can only be used on the data files in HFSQL format.
Hyper File 5.5 This parameter cannot be used.
Remarks

Use conditions

  • The HIndex function is used to re-index an xBase file.
  • Versions 21 and later
    The HIndex function allows to reindex the files of a cluster. In this case:
    • The reindex operation is performed on the node to which the user is connected.
    • Only a zero-downtime reindexing is available (hBackgroundTask constant).
    New in version 21
    The HIndex function allows to reindex the files of a cluster. In this case:
    • The reindex operation is performed on the node to which the user is connected.
    • Only a zero-downtime reindexing is available (hBackgroundTask constant).
    The HIndex function allows to reindex the files of a cluster. In this case:
    • The reindex operation is performed on the node to which the user is connected.
    • Only a zero-downtime reindexing is available (hBackgroundTask constant).
WINDEVWEBDEV - Server codeReports and QueriesUniversal Windows 10 AppiPhone/iPadUser code (UMC)External languageAjaxHFSQLHFSQL Client/Server

Automatic reindexing

Reindexing a data file can become necessary further to the loss or alteration of index file. An automatic reindex operation can be implemented for the data files.
To implement an automatic reindex operation, you must:
  • configure the value of variable H.AutoIndexingLimit.
    Indeed, if the data file contains less than H.AutoIndexingLimit records, the reindex operation is automatically performed if an index error occurs.
    The H.AutoIndexingLimit variable is set to 10000 by default. The automatic reindex operation is disabled if this variable is set to 0.
  • configure the value of variable H.VisibleAutoIndexing.
    If this value is set to True (default value), a window is automatically displayed as long as the automatic reindex operation is not completed. This window contains a progress bar used to follow the progress of the current reindexing. This window can be customized. For more details, see Assisted management of HFSQL errors.
    During the reindex operation, the different applications that use the file data (read or write records) will be temporarily stopped and/or locked until the end of the reindex operation.
    Versions 15 and later
    HFSQL Client/Server If the hBackgroundTask constant is used, the reindex operation is performed in background task and the applications that use the data file are not stopped.
    New in version 15
    HFSQL Client/Server If the hBackgroundTask constant is used, the reindex operation is performed in background task and the applications that use the data file are not stopped.
    HFSQL Client/Server If the hBackgroundTask constant is used, the reindex operation is performed in background task and the applications that use the data file are not stopped.
If an error occurs during the automatic reindex operation (lock error on the data file or on the record for example), the automatic reindex operation is stopped and a fatal error (corrupted index) is displayed. This operating mode is similar to the one without automatic reindexing.
Remarks:
  • During the automatic reindexing, the reindex operation is performed in normal mode (hNdxNormal constant).
  • No automatic reindexing is available for data files in Hyper File 5.5 format.
  • If an automatic reindexing is performed, the applications that use the data files currently reindexed are temporarily locked. A message is displayed, indicating that the file is currently maintained.
  • At the end of the reindex operation, the current HyperFileSQL context is automatically restored (except if a reindex operation with memo check was performed).
WINDEVWEBDEV - Server codeReports and QueriesUniversal Windows 10 AppAndroidAndroid Widget iPhone/iPadJavaUser code (UMC)AjaxHFSQLHFSQL Client/Server

"Zero-downtime" reindexing

A data file can be reindexed even when it is accessed by applications.
During the reindex operation, the different applications that use the file data (reading or writing records) will be temporarily stopped/locked until the end of the reindex operation.
WINDEV A window is displayed, indicating that the data file is currently reindexed (also called reorganization). This window is displayed during the entire reindex operation and it cannot be closed. A progress bar indicates the status of reindex operation.
This window can be customized and/or hidden. For more details, see Assisted management of HFSQL errors.
To avoid flashing effects, the indexing window is displayed only if the indexing operation may exceed 2 seconds. In this case, this window is displayed after 0.7 seconds.
Remark: no "live" reindexing can be performed if records are locked in read/write mode in the data file to reindex. If the records are locked in write mode only, the zero-downtime reindexing can still be performed.
Versions 15 and later
HFSQL Client/Server If the hBackgroundTask constant is used, the reindex operation is performed in background task and the applications that use the data file are not stopped.
New in version 15
HFSQL Client/Server If the hBackgroundTask constant is used, the reindex operation is performed in background task and the applications that use the data file are not stopped.
HFSQL Client/Server If the hBackgroundTask constant is used, the reindex operation is performed in background task and the applications that use the data file are not stopped.

Calculation of statistics

The statistical calculations are used to optimized the queries and the filters on the data file. This calculation only takes into account active records. This calculation can also be obtained with the HStatCalculate function.
Remark: For the calculation of statistics to be efficient, it is necessary to perform this calculation on all data files (for example in the case of a multi-file query).

Directory of temporary files

Temporary files can be created during the reindex operation. By default, these files are created in the Windows temporary directory or in the current directory if there is not enough space.
The H.TemporaryDirectory variable allows you to configure the directory used to save these temporary files. This variable is recommended when reindexing huge data files.
Versions 17 and later
HFSQL Client/Server The directory used to store the temporary files on the server can be defined:
New in version 17
HFSQL Client/Server The directory used to store the temporary files on the server can be defined:
HFSQL Client/Server The directory used to store the temporary files on the server can be defined:

Managing non-Latin character sets

To modify the character set used for the searches, the sorts:
  1. Specify the character set to use with ChangeCharset.
  2. Reindex the data file with HIndex. Use the constant hChangeCharset to take into account the alphabet specified with function ChangeCharset.
For more details, see Managing specific character sets in the data files.

Access rights to the data file

The reindex operation provokes the re-creation of the data file on disk. In an allocation system managing the rights at file level (NTFS...), the data file after the reindex operation will have the rights of the directory to which it belongs.
Before the reindex operation, if the data file had specific rights different from the rights of the folder, they must be redefined in Windows after the reindex operation.

Special case: Files corrupted after a computer reboot or a fatal error

The data files may be corrupted when the computer is unexpectedly rebooted. In this case, the data files contain invalid data (unreadable characters for example). To fix this problem:
  1. Perform a reindexing with deletion.
  2. Free the records in transaction with HTransactionFree.
  3. Delete the incorrect records with WDMAP.
WINDEV

Previous versions

This function replaces the HReindex_55function, which is retained for compatibility with WINDEV 5.5.
Component: wd270hf.dll
Minimum version required
  • Version 9
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