CASE
WHEN attribute1 = 1 THEN 'Apple'
WHEN attribute2 = 0 THEN 'Grape'
WHEN attribute3 >= 0 THEN 'Pear'
END

CASE WHEN attribute1 = 1 THEN 'Apple|' ELSE '' END
|| CASE WHEN attribute2 = 0 THEN 'Grape|' ELSE '' END
|| CASE WHEN attribute3 >= 0 THEN 'Pear|' ELSE '' END