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New WINDEV, WEBDEV, WINDEV Mobile 25 feature!
  • Read operation according to a key
  • Comparison between <Source>.Next and .ReadNext
  • Various
  • Locks
WINDEV
WindowsLinuxUniversal Windows 10 AppJavaReports and QueriesUser code (UMC)
WEBDEV
WindowsLinuxPHPWEBDEV - Browser code
WINDEV Mobile
AndroidAndroid Widget iPhone/iPadApple WatchUniversal Windows 10 AppWindows Mobile
Others
Stored procedures
Sets the position on the next data file record according to a browse item. The record is not read.
The number of the current record is modified when it is returned by <Source>.RecNum. For the functions that handle the current record number (<Source>.Delete, <Source>.Read, <Source>.Modify, ...), the value of this number is not updated: you must use <Source>.RecNum(). For example: not to do:
Customer.Delete()
but
Customer.Delete(Customer.RecNum())
The reading is performed from the lowest to the greatest value of the browse item (see the remarks for more details).
Caution: The record loaded in memory is not modified. The HFSQL variables (Customer.Name for example, which means the Name item of Customer file) are not updated.
In most cases, <Source>.Next sets the position in the data file to browse through the records that correspond to a condition. <Source>.Next is used to position on the next record corresponding to the condition.
Several cases may occur after the call to <Source>.Next:
  • a record corresponding to the condition was found: <Source>.Found returns True
  • the data file is empty or there is no record corresponding to the condition: <Source>.Out returns True
Remarks:
Versions 15 and later
Android This function is now available for the Android applications.
New in version 15
Android This function is now available for the Android applications.
Android This function is now available for the Android applications.
Versions 17 and later
iPhone/iPad This function is now available for the iPhone/iPad applications.
New in version 17
iPhone/iPad This function is now available for the iPhone/iPad applications.
iPhone/iPad This function is now available for the iPhone/iPad applications.
Versions 18 and later
Android Widget This function is now available in Android Widget mode.
Universal Windows 10 App This function is now available in Windows Store apps mode.
New in version 18
Android Widget This function is now available in Android Widget mode.
Universal Windows 10 App This function is now available in Windows Store apps mode.
Android Widget This function is now available in Android Widget mode.
Universal Windows 10 App This function is now available in Windows Store apps mode.
Remark: From version 19, HFSQL is the new name of HyperFileSQL.
Versions 21 and later
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.
New in version 21
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.

The read operation is performed from the lowest to the greatest value of the browse item (see remarks for more details).
Caution: The record loaded in memory is not modified. The HFSQL variables (Customer.Name for example, which means the Name item of Customer file) are not updated.
In most cases, <Source>.Next is used to position in the data file during a browse loop.
Several cases may occur after the call to <Source>.Next:
  • the data file is empty or no record corresponds to the filter (defined by <Source>.Filter): <Source>.Out returns True
  • the function tries to lock a record that is already locked in read-only: HErrorLock returns True and <Source>.Out returns True.
    Windows Mobile Locks are only managed on HFSQL Client/Server data files or data files handled by a Native Access. An HFSQL Mobile record cannot be locked. Indeed, the operating system of Pocket PC does not allow you to lock records.
    Java Access by JDBC: The management of locks is not available for databases accessed by JDBC.
Versions 15 and later
Android This function is now available for Android applications.
New in version 15
Android This function is now available for Android applications.
Android This function is now available for Android applications.
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.
Versions 18 and later
Android Widget This function is now available in Android Widget mode.
Universal Windows 10 App This function is now available in Windows Store apps mode.
New in version 18
Android Widget This function is now available in Android Widget mode.
Universal Windows 10 App This function is now available in Windows Store apps mode.
Android Widget This function is now available in Android Widget mode.
Universal Windows 10 App This function is now available in Windows Store apps mode.
Remark: From version 19, HFSQL is the new name of HyperFileSQL.
Versions 21 and later
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.
New in version 21
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.
Universal Windows 10 App This function is now available in Universal Windows 10 App mode.
Example
Customer.First(Name)
WHILE Customer.Out() = False
// Process the record
Customer.Next(Name)
END
Syntax
<Result> = <Source>.HNext([<Search key item> [, <Options>]])
<Result>: Boolean
  • True if the position was set,
  • False if an error occurred. This problem can be caused by:
<Source>: Type corresponding to the specified source
Name of HFSQL data file.
<Search key item>: Optional character string (with or without quotes)
Name of key item used to browse the data file. If this name is not specified, <Source>.Next will use the last browse item used on this data file by the last HFSQL management function (function starting with "H"). If this item does not exist, the best browse item is automatically used.
<Options>: Optional constant
Configures the lock and the management of duplicates performed on the record selected by <Source>.Next:
hLockWriteLock in write mode: the selected record can be read by another application but it cannot be modified by another application.
hLockReadWriteLock in read/write: the selected record cannot be read or modified by another application.
OLE DB Lock in write-only: the record currently read can be read by another application but it cannot be modified by another application.
Operating mode equivalent to the one of hLockWrite.
hLockNoNo lock (even if HStartLock was called): the record can be read or modified by another application.
hDistinctIf duplicates are found, it is used to position on a single record among the duplicates. This parameter is taken into account only if the browse is performed on a key item.
By default, all the duplicates are browsed.
OLE DBNative Connectors (Native Accesses) This constant is ignored.
Windows Mobile Locks are only managed on HFSQL Client/Server data files or data files handled by a Native Access. An HFSQL Mobile record cannot be locked. Indeed, the operating system of Pocket PC does not allow you to lock records.
Java Access by JDBC: This parameter is ignored.
OLE DBNative Connectors (Native Accesses) The lock options will have no effect if the locks are not supported by the OLE DB provider or by Native Access.
OLE DB The lock mode specified by <Source>.ReadFirst will remain effective during the calls to <Source>.ReadPrevious and <Source>.ReadNext.
To modify the lock mode, you must use:
Hyper File 5.5 The lock options are ignored. Use the lock functions (<Source>.LockRecNum) kept for backward compatibility.
Remarks

Read operation according to a key

<Source>.Next positions on the next record with the greatest key value. The sort order is the one that was specified in the analysis for this key.

Comparison between <Source>.Next and <Source>.ReadNext

<Source>.Next does not read the record: therefore, <Source>.Next is faster than <Source>.ReadNext.

Various

WINDEVWEBDEV - Server codeReports and QueriesiPhone/iPadUniversal Windows 10 AppJavaAjaxUser code (UMC)External languageHFSQLHFSQL Client/ServerHyper File 5.5OLE DBNative Connectors (Native Accesses)

Locks

By default (<Options> not specified), the record is not locked.
If a lock is requested (hLockWrite or hLockReadWrite constant), the position will be set on the record only if it is not already locked.
There is no need to specify a lock parameter if the data file is locked by HStartLock: the lock specified by HStartLock is automatically taken into account. To ignore the lock set by HStartLock, use the hLockNo constant.
Component : wd250hf.dll
Minimum version required
  • Version 25
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