USoft Rule Language examples: Query statements with subquery

The USoft Rule Language DO NOT ALLOW THAT keyword corresponds to the SQL WHERE keyword that introduces the first conditional clause ("WHERE-clause"). This is illustrated in the following examples.

USoft Rule Language

SQL Equivalent

FOR drivers d
DO NOT ALLOW THAT EXISTS
(
   SELECT      ''
   FROM        contract c
   ,           business_party b
   RELATE      b "PAYS FOR" c
   WHERE       b.id = d.id
   AND         c.paid = 'N'
)

SELECT         ''
FROM           driver d
WHERE EXISTS
(
   SELECT      ''
   FROM        contract c
   ,           business_party b
   RELATE      b "PAYS FOR" c
   WHERE       b.id = d.id
   AND         c.paid = 'N'
)

FOR drivers d
DO NOT ALLOW THAT 3 <
(
   SELECT      count(*)
   FROM        contract c
   ,           business_party b
   RELATE      b "PAYS FOR" c
   WHERE       b.id = d.id
   AND         c.paid = 'N'
)

SELECT         ''
FROM           driver d
WHERE 3 <
(
   SELECT      count(*)
   FROM        contract c
   ,           business_party b
   RELATE      b "PAYS FOR" c
   WHERE       b.id = d.id
   AND         c.paid = 'N'
)

FOR drivers d
DO NOT ALLOW THAT d.age <
(
SELECT a.minimum_age
FROM application a
)

SELECT         ''
FROM           driver d
WHERE d.age <
(
   SELECT      a.minimum_age
   FROM        application a
)