| Navigation: Language Reference > 13 - Built-in Functions >====== RESET (reset record sequence position) ====== |    |
| RESET | ( | view, string | ) | |
| view, file | ||||
| | sequence, string |
| RESET | Resets sequential processing to a specific record. |
| view | The label of a VIEW. |
| string | The string returned by the POSITION procedure. |
| file | The label of a component file of the VIEW. |
| sequence | The label of a FILE, KEY, or INDEX declaration. |
RESET resets sequential processing to a specific record.
VIEW Usage
RESET restores the VIEW to a previously read position in the return record set.
| RESET(view,string) | Resets to the record identified by the string that was returned by the POSITION procedure. Once RESET has restored the record pointer, either NEXT or PREVIOUS will read that record. |
| RESET(view,file) | Resets to the record identified by the current contents of the file's record buffer. This is used when the order of the VIEW is specified using PROP:Order and is equivalent to a RESET(view,string). |
The value contained in the position string (a value returned by the POSITION procedure) and its length, are file driver dependent. RESET is usually used in conjunction with POSITION to temporarily suspend and resume sequential VIEW processing.
FILE Usage
RESET restores the record pointer to the record identified by the string returned by the POSITION procedure. Once RESET has restored the record pointer, either NEXT or PREVIOUS will read that record.
The value contained in the string returned by the POSITION procedure, and its length, are dependent on the file driver. RESET is used in conjunction with POSITION to temporarily suspend and resume sequential file processing.
Errors Posted:
| 33 | Record Not Available |
| 37 | File Not Open |
| 78 | Invalid number of parameters (string parameter is too small) |
Example:
ViewOrder VIEW(Customer) !Declare VIEW structure
PROJECT(Cus:AcctNumber,Cus:Name)
JOIN(Hea:AcctKey,Cus:AcctNumber) !Join Header file
PROJECT(Hea:OrderNumber)
JOIN(Dtl:OrderKey,Hea:OrderNumber) !Join Detail file
PROJECT(Det:Item,Det:Quantity)
JOIN(Pro:ItemKey,Dtl:Item) !Join Product file
PROJECT(Pro:Description,Pro:Price)
END
END
END
END
RecordQue QUEUE,PRE(Que)
AcctNumber LIKE(Cus:AcctNumber)
Name LIKE(Cus:Name)
OrderNumber LIKE(Hea:OrderNumber)
Item LIKE(Det:Item)
Quantity LIKE(Det:Quantity)
Description LIKE(Pro:Description)
Price LIKE(Pro:Price)
END
SavPosition STRING(260)
CODE
OPEN(Customer,22h)
OPEN(Header,22h)
OPEN(Detail,22h)
OPEN(Product,22h)
SET(Cus:AcctKey)
OPEN(ViewOrder) !Top of file in keyed sequence
LOOP !Read all records in file
NEXT(ViewOrder) ! read a record sequentially
IF ERRORCODE()
DO DisplayQue
BREAK
END
RecordQue :=: Cus:Record !Move record into queue
RecordQue :=: Hea:Record !Move record into queue
RecordQue :=: Dtl:Record !Move record into queue
RecordQue :=: Pro:Record !Move record into queue
ADD(RecordQue) ! and add it
ASSERT(NOT ERRORCODE())
IF RECORDS(RecordQue) = 20 !20 records in queue?
DO DisplayQue !Display the queue
END
END !End loop
DisplayQue ROUTINE
SavPosition = POSITION(ViewOrder) !Save record position
DO ProcessQue !Display the queue
FREE(RecordQue) !and free it
RESET(ViewOrder,SavPosition) !Reset the record pointer
NEXT(ViewOrder) !and get the record again
See Also: