- Read operation according to a key item or not
- Memos
- Various
- Lock
<Source>.Backward (Function) In french: <Source>.Recule
 Not available with this kind of connection
// Go back to the 200th record of the Customer data file
// according to the CustName key
Customer.ReadLast(CustName)
Customer.Backward(CustName, 199)
Syntax
<Result> = <Source>.Backward([<Item> [, <Step> [, <Options>]]])
<Result>: Boolean - True if the backward move was performed in the data file,
- False if an error occurred (lock, end of file, etc.): the record is not read. HError is used to identify the error.
<Source>: Type corresponding to the specified source Name of data file, view or query used. <Item>: Optional character string (with or without quotes) Name of item according to which the browse is performed. If this name is not specified, <Source>.Backward handles the last file item used by the last function for HFSQL management (starting with the letter H).
<Step>: Optional integer Number of steps backward (which means number of records to browse). By default, <Step> = 1. <Options>: Optional Integer constant (or combination of constants) Configures:- the lock mode applied to the record read. By default, the lock performed corresponds to the current lock.
| | | hLockNo | No lock (even if HStartLock was called): the record can be read or modified by another application during the reading. | | hLockWrite | Lock in write mode: the record currently read can be read by another application but it cannot be modified by another application. | | hLockReadWrite | Lock in read/write: the record currently read cannot be read or modified by another application. |
 Locks are managed only on HFSQL Client/Server data files or on data files handled by a Native Connector. An HFSQL Mobile record cannot be locked. Indeed, the operating system of Pocket PC does not allow you to lock records.
  The lock options will have no effect if the locks are not supported by the OLE DB provider or by the Native Connector. - the management of duplicates during the browse. By default, all the duplicates are browsed.
| | | hDistinct | When a browse is performed on a key item, a single record is browsed if duplicates are found. |
Remarks Read operation according to a key item or not If the item used is a key item: - if the hDistinct constant is not enabled, <Source>.Backward moves backward of <Step> key values from the current position.
- if the hDistinct constant is enabled, <Source>.Backward moves backward of <Step> distinct key values from the current position. If duplicates are found, a single duplicate is read.
If the item used is not a key item: - the hDistinct constant is not available,
- <Source>.Backward moves backward of <Step> active records from the current position.
Memos The memos associated with the record can be automatically read (or not) when reading the record. <Source>.SetMemo is used to customize this automatic read operation. If the memos are supported, the associated text memos are read when the record is read. The binary memos are read only when they are explicitly used ( <Source>.ExtractMemo).
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