Changes between Version 1 and Version 2 of AdvancedReport18

Timestamp:

12/29/25 20:05:36 (5 days ago)

Author:

211101

Comment:

--

AdvancedReport18

@@ -1 @@
-===== Сметки со највисоко вкупно трошење во изминатата година
+==== Сметки со највисоко вкупно трошење во изминатата година
 {{{#!sql
-SELECT 
-    ta.account_name, 
-    SUM(tb.spent_amount) AS total_spent
-FROM 
-    transaction_breakdown tb
-JOIN transaction t ON tb.transaction_id = t.transaction_id
-JOIN transaction_account ta ON tb.transaction_account_id = ta.transaction_account_id
-WHERE 
-    t.date >= NOW() - INTERVAL '1 YEAR'
-GROUP BY 
-    ta.account_name
-ORDER BY 
-    total_spent DESC
-LIMIT 10;
+CREATE OR REPLACE FUNCTION get_top_accounts_last_year()
+RETURNS TABLE (
+    account_name TEXT,
+    total_spent NUMERIC
+)
+LANGUAGE plpgsql
+AS $$
+BEGIN
+    RETURN QUERY
+    SELECT 
+        ta.account_name, 
+        COALESCE(SUM(tb.spent_amount), 0) AS total_spent
+    FROM transaction_breakdown tb
+    JOIN transaction t 
+        ON tb.transaction_id = t.transaction_id
+    JOIN transaction_account ta 
+        ON tb.transaction_account_id = ta.transaction_account_id
+    WHERE t.date >= NOW() - INTERVAL '1 YEAR'
+    GROUP BY ta.account_name
+    ORDER BY total_spent DESC
+    LIMIT 10;
+END;
+$$;
 }}}
+
+==== Релациона алгебра
+- TA(transaction_account_id, account_name)
+- TB(transaction_id, transaction_account_id, spent_amount)
+- T(transaction_id, date)
+
+JOIN на табелите:
+- J1 ← TA ⨝,,TA.transaction_account_id = TB.transaction_account_id,, TB
+- J2 ← J1 ⨝,,TB.transaction_id = T.transaction_id,, T
+
+Филтрирање по последна година:
+- F ← σ,,date >= NOW() - INTERVAL '1 YEAR',, (J2)
+
+Групирање и агрегација по сметка:
+- G ← γ,,account_name; SUM(spent_amount) → total_spent,,(F)
+
+Подредување по вкупно потрошено и лимитирање:
+- R_final ← τ,,total_spent DESC LIMIT 10,,(G)