Is this question about Redshift or Postgres? If it's Redshift then Joachim Isaksson's answer will not work because Redshift does not support functions.
I use the follow view to see table permissions. It's loosely based on something from Redshift forum but unfortunately I didn't make a note of the source.
/* List of all Grants currently in place. */
CREATE VIEW admin.vw_table_grants
AS
SELECT relacl
,'GRANT '
|| SUBSTRING(
CASE WHEN CHARINDEX('r', SPLIT_PART( SPLIT_PART( ARRAY_TO_STRING( RELACL, '|' ), pu.groname, 2 ) , '/', 1 ) ) > 0 THEN ', SELECT' ELSE '' END
|| CASE WHEN CHARINDEX('w', SPLIT_PART( SPLIT_PART( ARRAY_TO_STRING( RELACL, '|' ), pu.groname, 2 ) , '/', 1 ) ) > 0 THEN ', UPDATE' ELSE '' END
|| CASE WHEN CHARINDEX('a', SPLIT_PART( SPLIT_PART( ARRAY_TO_STRING( RELACL, '|' ), pu.groname, 2 ) , '/', 1 ) ) > 0 THEN ', INSERT' ELSE '' END
|| CASE WHEN CHARINDEX('d', SPLIT_PART( SPLIT_PART( ARRAY_TO_STRING( RELACL, '|' ), pu.groname, 2 ) , '/', 1 ) ) > 0 THEN ', DELETE' ELSE '' END
|| CASE WHEN CHARINDEX('R', SPLIT_PART( SPLIT_PART( ARRAY_TO_STRING( RELACL, '|' ), pu.groname, 2 ) , '/', 1 ) ) > 0 THEN ', RULE' ELSE '' END
|| CASE WHEN CHARINDEX('x', SPLIT_PART( SPLIT_PART( ARRAY_TO_STRING( RELACL, '|' ), pu.groname, 2 ) , '/', 1 ) ) > 0 THEN ', REFERENCES' ELSE '' END
|| CASE WHEN CHARINDEX('t', SPLIT_PART( SPLIT_PART( ARRAY_TO_STRING( RELACL, '|' ), pu.groname, 2 ) , '/', 1 ) ) > 0 THEN ', TRIGGER' ELSE '' END
|| CASE WHEN CHARINDEX('X', SPLIT_PART( SPLIT_PART( ARRAY_TO_STRING( RELACL, '|' ), pu.groname, 2 ) , '/', 1 ) ) > 0 THEN ', EXECUTE' ELSE '' END
|| CASE WHEN CHARINDEX('U', SPLIT_PART( SPLIT_PART( ARRAY_TO_STRING( RELACL, '|' ), pu.groname, 2 ) , '/', 1 ) ) > 0 THEN ', USAGE' ELSE '' END
|| CASE WHEN CHARINDEX('C', SPLIT_PART( SPLIT_PART( ARRAY_TO_STRING( RELACL, '|' ), pu.groname, 2 ) , '/', 1 ) ) > 0 THEN ', CREATE' ELSE '' END
|| CASE WHEN CHARINDEX('T', SPLIT_PART( SPLIT_PART( ARRAY_TO_STRING( RELACL, '|' ), pu.groname, 2 ) , '/', 1 ) ) > 0 THEN ', TEMPORARY' ELSE '' END
, 3,10000)
|| ' ON '|| namespace ||'.'|| item ||' TO '|| pu.groname ||' ;' AS grantsql
FROM (SELECT use.usename AS subject
,nsp.nspname AS namespace
,cls.relname AS item
,cls.relkind AS type
,use2.usename AS owner
,cls.relacl
FROM pg_user use
CROSS JOIN pg_class cls
LEFT JOIN pg_namespace nsp
ON cls.relnamespace = nsp.oid
LEFT JOIN pg_user use2
ON cls.relowner = use2.usesysid
WHERE cls.relowner = use.usesysid
AND nsp.nspname NOT IN ('pg_catalog', 'pg_toast', 'information_schema')
ORDER BY subject
,namespace
,item )
JOIN pg_group pu ON array_to_string(relacl, '|') LIKE '%'|| pu.groname ||'%'
WHERE relacl IS NOT NULL
ORDER BY 2