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- Read operation according to a key item or not
- Memos
- Miscellaneous
- Lock
<Source>.Backward (Function) In french: <Source>.Recule
Not available with this kind of connection
Moves backward several records from the current position in the data file, according to a specified item. The destination Record is read and loaded into memory: HFSQL variables are updated (e.g. Customer.Name, i.e. the field Name field of the Client). Several cases may occur after the call to <Source>.Backward: - there are no more records in the data file: function <Source>.Out returns True. No read operation is performed.
- the function attempts to block a record already blocked in play mode: function HErrorLock returns True and function <Source>.Out returns True.
Management of locks not available in PHP.
JDBC access: Lock management is not available for databases accessed via JDBC.
This function can be used with the data files, HFSQL views or queries.
Client.LitDernier(NomCli)
Client.Recule(NomCli, 199)
Syntax
<Result> = <Source>.Backward([<Item> [, <Step> [, <Options>]]])
<Result>: Boolean - True if the backward move was performed in the data file,
- False in case of error (block, end of data file, etc.): the record is not read. HError is used to identify the error.
<Source>: Type corresponding to the specified source Name of the data file, view or query used. <Item>: Optional character string Name of item according to which the browse is performed. If this name is not specified, <Source>.Backward handles the last item in the data file used by the last HFSQL function (function starting with "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 blocking: the Record can be played back or modified by another application during playback. | hLockReadWrite | Read/write lock: the record being read cannot be read or modified by another application. | hLockWrite | Write lock: the record currently read can be read by another application but it cannot be modified by another application. |
 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 duplicates are iterated over.
| | hDistinct | Only one record is read if duplicates are found when looping through a key item. |
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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