Try this

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* TestUpdateSubQuery.prg

LOCAL i

#DEFINE TEST_RECORD 10

CREATE TABLE TestUpdate FREE ( ;
pkey i( 4 ), ;
datavalue i( 4 ) ;
)

FOR i = 1 to 10 STEP 1
INSERT INTO TestUpdate ( pkey, datavalue ) ;
VALUES ( i, i )
ENDFOR

SELECT * FROM TestUpdate

SELECT * FROM TestUpdate WHERE pkey == TEST_RECORD INTO CURSOR rcurRefUpdate

UPDATE TestUpdate ;
SET datavalue = GetNewValue() ;
WHERE pkey IN ( ;
SELECT pkey FROM rcurRefUpdate ;
)

SELECT * FROM TestUpdate

CLOSE ALL

RETURN .T.


FUNCTION GetNewValue()

RETURN 25

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This is a simple example, but it illustrates that a column in a subset of rows can be updated (to a single value) in this fashion.

Hope this helps,

John