| Navigation: Language Reference > 13 - Built-in Functions >====== NEXT (read next record in sequence) ====== |    |
NEXT( entity )
| NEXT | Reads the next record in sequence from a FILE or VIEW. |
| entity | The label of a FILE or VIEW declaration. |
NEXT reads the next record in sequence from a FILE or VIEW. The SET (or RESET) statement determines the sequence in which records are read. The first NEXT following a SET reads the record at the position specified by the SET statement. Subsequent NEXT statements read subsequent records in that sequence. The sequence is not affected by any GET, REGET, ADD, PUT, or DELETE. Executing NEXT without a preceding SET, or attempting to read past the end of file posts the “Record Not Available” error.
FILE Usage
NEXT reads the next record in sequence from the data FILE and places it in the RECORD structure data buffer.
VIEW Usage
NEXT reads the next record(s) in sequence from a VIEW and places the appropriate fields in the VIEW structure component files' data buffer(s). If the VIEW contains JOIN structures, NEXT retrieves the appropriate next set of related records.
Either the last SET statement issued on the VIEW's primary file before the OPEN(view) statement, or the SET(view) statement issued after the OPEN(view) determines the sequence in which records are read.
Errors Posted:
| 33 | Record Not Available |
| 37 | File Not Open |
| 43 | Record Is Already Held |
| 90 | Driver Specific Error (returned by FILEERRORCODE) |
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)
END
END
END
CODE
OPEN(Customer,22h)
SET(Cus:NameKey) !Beginning of file in keyed sequence
LOOP !Read all records through end of file
NEXT(Customer) !read a record sequentially
IF ERRORCODE() THEN BREAK. !break on end of file
DO PostTrans !call transaction posting routine
END
OPEN((Header,22h)
OPEN(Detail,22h)
OPEN(Product,22h)
SET(Cus:AcctKey)
OPEN(ViewOrder)
LOOP !Read all records through end of primary file
NEXT(ViewOrder) !read a record sequentially
IF ERRORCODE() THEN BREAK. !break on end of file
DO PostTrans !call transaction posting routine
END !End loop
See Also: