spec-ql.clj

;; [ WITH [ RECURSIVE ] with_query [, ...] ]
;; SELECT [ ALL | DISTINCT [ ON ( expression [, ...] ) ] ]
;;     * | expression [ [ AS ] output_name ] [, ...]
;;     [ FROM from_item [, ...] ]
;;     [ WHERE condition ]
;;     [ GROUP BY expression [, ...] ]
;;     [ HAVING condition [, ...] ]
;;     [ WINDOW window_name AS ( window_definition ) [, ...] ]
;;     [ { UNION | INTERSECT | EXCEPT } [ ALL ] select ]
;;     [ ORDER BY expression [ ASC | DESC | USING operator ] [ NULLS { FIRST | LAST } ] [, ...] ]
;;     [ LIMIT { count | ALL } ]
;;     [ OFFSET start [ ROW | ROWS ] ]
;;     [ FETCH { FIRST | NEXT } [ count ] { ROW | ROWS } ONLY ]
;;     [ FOR { UPDATE | SHARE } [ OF table_name [, ...] ] [ NOWAIT ] [...] ]

;; where from_item can be one of:

;;     [ ONLY ] table_name [ * ] [ [ AS ] alias [ ( column_alias [, ...] ) ] ]
;;     ( select ) [ AS ] alias [ ( column_alias [, ...] ) ]
;;     with_query_name [ [ AS ] alias [ ( column_alias [, ...] ) ] ]
;;     function_name ( [ argument [, ...] ] ) [ AS ] alias [ ( column_alias [, ...] | column_definition [, ...] ) ]
;;     function_name ( [ argument [, ...] ] ) AS ( column_definition [, ...] )
;;     from_item [ NATURAL ] join_type from_item [ ON join_condition | USING ( join_column [, ...] ) ]

;; and with_query is:

;;     with_query_name [ ( column_name [, ...] ) ] AS ( select )

;; TABLE { [ ONLY ] table_name [ * ] | with_query_name }

(s/def ::with
  (s/cat :with #{:with} :recursive (s/? #{:recursive})))

(s/def ::distinct-on
  (s/cat :distinct #{:distinct} :on #{:on} :expression (constantly true)))

(s/def ::select-expression
  (s/cat :select #{:select}
         :distinct (s/or :all #{:all} :distinct #{:distinct} :distinct-on ::distinct-on)))

(s/def ::select-query
  (s/cat :common-table-expressions (s/? (s/coll-of ::with))
         :select-expression ::select-expression))