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- Read operation based on a key
- Comparison between HNext and HReadNext
- Miscellaneous
- Locks
HNext (Function) In french: HSuivant
 Not available with this kind of connection
Sets the position on the next table record 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 that handle the current record number ( HDelete, HRead, HModify, etc.), the value of this number is not updated. You need to use HRecNum(). For example, you should not write:
but
HDelete(Customer, HRecNum())
Values in the browse item are read in ascending order (for more details, see the remarks). Warning: Record 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. Generally, HNext sets the position in the table during a loop operation. Several cases may occur after the call to HNext: - the table is empty or there is no record corresponding to the filter (defined by function HFilter): function HOut returns True
- the function attempts to block a record already blocked in play mode: function HErrorLock returns True and function HOut returns True.
 JDBC access: Lock management is not available for databases accessed via JDBC.
HFirst(Customer, Name)
WHILE HOut(Customer) = False
HNext(Customer, Name)
END
Syntax
<Result> = HNext([<Table> [, <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 table, etc.): function HFound returns False and function HError returns 0.
- an error: HError returns an integer other than 0. HErrorInfo returns more details.
<Table>: Optional character string Name of the HFSQL table. If this parameter is an empty string (""), HNext manipulates the last table 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 table. If this name is not specified, HNext will use the last browse item used on this table 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 HNext: | | | hDistinct | If there are any duplicates, sets the position on a single record of the duplicates. This parameter is taken into account only if the iteration is performed on a key item.
By default, all duplicates are iterated over.
| | hLockNo | No blocking: the Record 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. |
To change the lock mode, use: Remarks Read operation based on a key HNext positions on the next record with the greatest key value. The sort order taken into account is the one specified in the database schema for this key. Comparison between HNext and HReadNext The function HNext function does not play the Record: the HNext is therefore faster than function HReadNext. Miscellaneous - HRecNum returns the current record number.
- HChangeKey changes the search key while keeping the position on the current record.
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