FIND-UNIQUE( ) method

Gets a single record. This method lets a user get a unique record that satisfies the predicate expression.

Return type:

LOGICAL

Applies to:

Buffer object handle

 

Syntax 

FIND-UNIQUE ( predicate-expression [ , lockmode [ , wait-mode ] ] )

predicate-expression

A character expression that evaluates to the following syntax:

 

Syntax 

[ WHERE [ logical-expression ] ] [ USE-INDEX index-name ]

Once evaluated, predicate-expression can contain only constants and unabbreviated references to fields from the buffer. The predicate-expression itself can be built using a concatenation of character expressions.

lockmode

An integer expression evaluating to one of the following constants: SHARE-LOCK, EXCLUSIVE-LOCK, or NO-LOCK. You can assign NO-LOCK to an integer variable. For example, mylock = NO-LOCK.

The default is SHARE-LOCK.

waitmode

An integer expression evaluating to one of the following: NO-WAIT, 0, or the Unknown value (?). The default is to wait.

You can assign NO-WAIT to an integer variable. For example, mywait = NO-WAIT.

The following shows some examples of the FIND-UNIQUE method:

 

DEFINE VARIABLE bh     AS HANDLE    NO-UNDO. DEFINE VARIABLE myname AS CHARACTER NO-UNDO.   bh = BUFFER Customer:HANDLE.   bh:FIND-UNIQUE("WHERE Customer.Custnum < 3 AND Customer.Name = 'lift line skiing'").   bh:FIND-UNIQUE("WHERE Customer.CustNum = 30"). bh:FIND-UNIQUE("WHERE Customer.Name = " + QUOTER(myname). MESSAGE bh:AMBIGUOUS.

If FIND-UNIQUE succeeds, it returns TRUE, otherwise it returns FALSE.

If FIND-UNIQUE fails, a message displays. You can suppress this message using NO-ERROR on the statement containing the method.

If more than one record satisfies the predicate expression, then the AMBIGUOUS attribute is set to TRUE.

See also:

FIND-FIRST( ) method, FIND-CURRENT( ) method, FIND-LAST( ) method, FIND statement