convert rollfoward to function

schema/functions/rollforward.sql

@@ -1,33 +1,29 @@
-WITH
---min and max periods
-minmax AS (
-    SELECT
-    (SELECT lower(dur) FROM evt.fspr WHERE id = '2018.08') mind
-    ,(SELECT lower(dur) FROM evt.fspr WHERE id = '2018.11') maxd
-)
---list each period in min and max
-,prng AS (
+CREATE FUNCTION evt.balrf(_mind tstzrange, _maxd tstzrange) RETURNS void AS
+$func$
+BEGIN
+    WITH
+    --list each period in min and max
+    prng AS (
         SELECT 
             id
             ,dur
             ,prop
         FROM
             evt.fspr f
-        CROSS JOIN minmax
         WHERE
-        lower(f.dur) >= mind
-        AND lower(f.dur) <= maxd
-)
---get every account involved in target range
-,arng AS (
+            f.dur >= _mind
+            AND f.dur <= _maxd
+    )
+    --get every account involved in target range
+    ,arng AS (
         SELECT DISTINCT
             acct
         FROM
             evt.bal b
             INNER JOIN prng ON
                 prng.id = b.fspr
-)
-,bld AS (
+    )
+    ,bld AS (
         WITH RECURSIVE rf (acct, id, dur, propr, obal, debits, credits, cbal) AS
         (
             SELECT
@@ -69,20 +65,23 @@ minmax AS (
                 lower(f.dur) <= (SELECT maxd FROM minmax)
         ) 
         select * from rf
-)
-INSERT INTO
+    )
+    INSERT INTO
         evt.bal
-SELECT
+    SELECT
         acct
         ,id
         ,obal
         ,debits
         ,credits
         ,cbal
-FROM 
+    FROM 
         bld
-ON CONFLICT ON CONSTRAINT bal_pk DO UPDATE SET
+    ON CONFLICT ON CONSTRAINT bal_pk DO UPDATE SET
         obal = EXCLUDED.obal
         ,debits = EXCLUDED.debits
         ,credits = EXCLUDED.credits
-    ,cbal = EXCLUDED.cbal
+        ,cbal = EXCLUDED.cbal;
+END;
+$func$
+LANGUAGE plpgsql