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- Read operation based on a key
- Password verification
- Miscellaneous
- Comparing HReadLast and HLast
- Locks
HLast (Function) In french: HDernier
 Not available with this kind of connection
Sets the position on the last record of a data file according to a browse item. The record is not read. The number of the current record is modified only when it is returned by HRecNum. For functions handling the current record number by default (functions HDelete, HRead, HModify, ...), the value of this number is not updated: you must use the HRecNum() function.. For example: do not:
but
HDelete(Client, HRecNum())
Values in the browse item are read in ascending order (see Remarks for more details). Warning: Recording loaded into memory is not modified. The HFSQL variables (for example Customer.Name, i.e. the Name item of the Customer file) are not updated. In most cases, HLast sets the position in the data file to loop through the records that match a condition. HNext is used to position on the next record corresponding to the condition. Several cases may occur after the call to HLast: - a record matching the condition has been found: function HFound returns True
- the data file is empty or there is no record corresponding to the condition: function HOut returns True
Remarks: - By default, HSeekFirst and HSeekLast are used to perform an exact-match search.
- By default, HLast performs a generic search.
The highest value in the browse item is read (for more details, see remarks). Caution: Recording loaded into memory is not modified. HFSQL variables (e. g. Customer.Name, or the Name item of the Customer data file) are not updated. In most cases, HLast is used to set the 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): function HOut returns True.
- the function attempts to block a record already blocked in playback: function HErrorLock returns True and function HOut returns True.
 JDBC access: lock management is not supported for databases that are accessed through JDBC.
 Management of locks not available in SQLite databases.
HLast(Client, Nom)
WHILE NOT HOut()
HPrevious(Client, Nom)
END
Syntax
<Result> = HLast([<Data file>] [, <Search key item> [, <Options>]])
<Result>: Boolean - True if the position was set,
- False if an error occurs. This problem can be caused by:
- or a positioning problem (empty data file, etc.): function HFound returns Faux and function HError returns 0.
- an error: HError returns an integer other than 0. HErrorInfo returns more details.
<Data file>: Optional character string Name of the data file used. If this parameter is an empty string (""), HLast manipulates the last data file used by the last HFSQL function (function starting with "H"). <Search key item>: Optional character string Name of the key item used to loop through the data file. If this name is not specified, HLast 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 set on the record selected by HLast: | | | hKeepFilter | The filter set by HFilter will be taken into account, even if the search key is not optimized for the filter. Reminder: HFilter returns the optimized search key for the filter.
Caution: in this case, on large data files, performance problems may occur..
| | hLockNo | No blocking: the recording can be played back or modified by another application. | | hLockReadWrite | Lock in read/write mode: the selected record cannot be read or modified by another application. | | hLockWrite | Lock in write mode: the selected record can be read by another application, but cannot be modified by another application..
| | hNoRefresh | |
Remarks Read operation based on a key HLast sets the position on the record with the greatest key value. The sort order taken into account is the one specified in the analysis for this key. If duplicates are found, HLast sets the position on the first "duplicate" record according to the sequence of record numbers. Miscellaneous - HRecNum returns the current record number.
- HChangeKey changes the search key while keeping the position on the current record.
Comparing HReadLast and HLast The HLast function does not read the recording: the HLast function is therefore faster than the HReadLast function.
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