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  • Read operation according to a key
  • Checking the password
  • Various
  • Comparing HReadLast and HLast
  • 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
Positions on the last file record according to a search item. The record is not read.
The number of the current record is modified when it is returned by HRecNum. For the functions that handle the current record number (HDelete, HRead, HModify, ...), the value of this number is not updated: you must use HRecNum(). For example: not to do:
HDelete(Customer)
but
HDelete(Customer, HRecNum())
The reading is performed for the greatest value of search 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, HLast is used to position in the data file in order to perform a read loop with HPrevious.
Several cases may occur after the call to HLast:
  • the data file is empty or there is no record corresponding to the filter (defined by HFilter): HOut returns True.
  • the function tries to lock a record that is already locked in read-only: HErrorLock returns True and HOut returns True.
    Windows Mobile The management of locks is performed on the HFSQL Client/Server data files and on the data files handled by Native Access. A 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 the databases accessed by JDBC.
    Android The management of locks is not available for the SQLite databases.
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.
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.
Note: From version 19, HFSQL is the new name of HyperFileSQL.
Example
// Browse a file from the last record
HLast(Customer, Name)
WHILE NOT HOut()
        // Process the record
        HPrevious(Customer, Name)
END
Syntax
<Result> = HLast([<File Name> [, <Name of Search Key Item>] [, <Options>]])
<Result>: Boolean
  • True if the positioning was performed,
  • False if an error occurred. This problem can be caused by:
    • a positioning problem (empty data file, ...): HFound returns False and HError returns 0.
    • an error: HError returns an integer other than 0. HErrorInfo returns more details.
<File Name>: Optional character string (with or without quotes)
Name of data file used. If this parameter corresponds to an empty string (""), HLast handles the last data file used by the last function for HFSQL management (starting with the letter H).
<Name of 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, HLast handles the last search item used on this data file by the last function for HFSQL management (starting with the letter H). If this item does not exist, the best search item is automatically used.
<Options>: Optional constant
Configures the lock performed on the record selected by HLast:
hLockWriteLock in write mode: the selected record can be read by another application but it cannot be modified by another application.
Java Access by JDBC: This constant is not available.
hKeepFilterThe filter implemented by HFilter will be taken into account, even if the search key is not optimized for the filter. Reminder: HFilter returns the search key optimized for the filter.
Caution: in this case, poor performance may occur on huge data files.
Hyper File 5.5 This constant cannot be used.
hLockReadWriteLock in read/write: the selected record cannot be read or modified by another application.
hLockNoNo lock (even if HStartLock was called): the record can be read or modified by another application.
hNoRefresh
OLE DBNative Accesses The table or query content will not be refreshed. All the saved positions are stored.
If this parameter is not specified, HLast reinitializes the browse for the specified item: the content of table or query is refreshed with the data found in the OLE DB database. All the saved positions are lost. The position will be restored according to the value of best item.
Note: The browses and the positions saved on the other items are not affected.
Windows Mobile The management of locks is performed on the HFSQL Client/Server data files and on the data files handled by native access. A HFSQL Mobile record cannot be locked. Indeed, the operating system of Pocket PC does not allow you to lock records.
OLE DBNative Accesses The lock options will have no effect if the locks are not supported by the OLE DB provider or by the Native Access.
Hyper File 5.5 The lock options are ignored. Use the lock functions (HLockRecNum) kept for backward compatibility.
Java Access by JDBC: The management of locks is not available for the databases accessed by JDBC.
AndroidAndroid Widget The management of locks is not available for the SQLite databases.
Remarks

Read operation according to a key

HLast positions on the record with the greatest key value.
The sort order is the one that was specified in the analysis for this key.
If duplicates are found, HLast positions on the last "duplicate" record according to the sequence of record numbers.
WINDEVWEBDEV - Server codeReports and QueriesiPhone/iPadWindows MobileUniversal Windows 10 AppJavaAjaxUser code (UMC)HFSQLHFSQL Client/ServerHyper File 5.5

Checking the password

If HLast is the first function that handles the specified data file, the password is checked when the data file is opened.
If the password is incorrect, HErrorPassword returns True and HOut returns True.

Various

  • The current record number is returned by HRecNum.
  • HChangeKey is used to modify the search key while being positioned on the current record.

Comparing HReadLast and HLast

HLast does not read the record: therefore, HLast is faster than HReadLast.
WINDEVWEBDEV - Server codeReports and QueriesiPhone/iPadJavaAjaxUser code (UMC)HFSQLHFSQL Client/ServerHyper File 5.5OLE DBNative Accesses

Locks

By default (<Options> not specified), no lock operation is performed on the record.
If a lock is requested (hLockWrite or hLockReadWrite constant), the positioning on the record will be performed only if this record 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 specified by HStartLock, use the hLockNo constant.
Components
WINDEVWEBDEV - Server codeReports and Queries wd230hf.dll
Windows Mobile wp230hf.dll
Java wd230java.jar
Linux wd230hf.so
Android wd230android.jar
Minimum required version
  • Version 9
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