Fetch (get a specific record by key value)

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Fetch( key ), VIRTUAL, PROC

Fetch

Gets a specific record by its key value and handles any errors.

key

The label of the primed KEY.

The Fetch method gets a specific record by its key value and handles any errors. You must prime the key before calling Fetch. If the key is not unique, Fetch gets the first record with the specified key value.

The TryFetch method provides a slightly different (manual) alternative for fetching specific records.

Implementation: Fetch tries to get the specified record. If it succeeds, it returns Level:Benign (declared in ABERROR.INC). If it fails, it returns Level:Notify (also declared in ABERROR.INC) and clears the record buffer. See Error Class for more information on severity levels.

Return Data Type:     BYTE

Example:

PROGRAM

INCLUDE('ABFILE.INC')             !declare FileManager class

MAP                               !program map

END

GlobalErrors  ErrorClass           !declare GlobalErrors object

Access:States  CLASS(FileManager)  !declare Access:States object

        END

 

States     FILE,DRIVER('TOPSPEED'),PRE(ST),CREATE,BINDABLE,THREAD

StateCodeKey KEY(ST:StateCode),NOCASE,OPT,PRIMARY

Record       RECORD,PRE()

StateCode     STRING(2)

State         STRING(20)

            END

          END

CODE

!program code

!get the state record for Florida

ST:StateCode = 'FL'                     !prime the state key for the fetch

Access:States.Fetch(ST:StateCodeKey)    !fetch the record and handle any errors

 

See Also:     TryFetch