initial swipe at insert

schema/triggers/gl_insert.sql

@@ -0,0 +1,36 @@
+---------------------------handle new gl lines----------------------------------------
+
+CREATE OR REPLACE FUNCTION evt.gl_insert() RETURNS trigger
+    LANGUAGE plpgsql
+    AS 
+    $func$
+    --upsert gl balance
+    --if a new period is created roll any gaps
+    WITH
+    agg AS (
+        SELECT
+            acct
+            ,fspr
+            ,sum(amount) FILTER (WHERE amount > 0) debits
+            ,sum(amount) FILTER (WHERE amount < 0) credits
+        FROM
+            ins
+        GROUP BY
+            acct
+            ,fspr
+    )
+    INSERT INTO
+        evt.bal
+    SELECT
+        acct
+        ,fspr
+        ,0
+        ,debits
+        ,credits
+        ,debits + credits
+    FROM
+        agg
+    ON CONFLICT ON CONSTRAINT PRIMARY KEY DO UPDATE SET
+        debits = debits + EXCLUDED.debits
+        ,credits = credits + EXCLUDED.credits
+        ,cbal = cbal + debits + credits