Query for getting all the Flex Values for a given Flex Structure/Segment Name:

SELECT
ffvv.flex_value
FROM
fnd_id_flex_structures fifs,
fnd_id_flex_segments fifs1,
fnd_flex_values_vl ffvv
WHERE
UPPER(fifs.id_flex_structure_code) = UPPER('UK_JOBS')
AND fifs.id_flex_num = fifs1.id_flex_num
AND UPPER(fifs1.segment_name) = UPPER('Job Name')
AND fifs1.flex_value_set_id = ffvv.flex_value_set_id;

The following Query is for getting all the Flex Values for a given Flex
Value Set:

SELECT
ffvv.flex_value
FROM  
fnd_flex_values_vl ffvv,
fnd_flex_value_sets ffvs  
WHERE
ffvv.flex_value_set_id    = ffvs.flex_value_set_id
AND UPPER(ffvs.flex_value_set_name) = UPPER('UK_JOB_NAME');