Moved accumulation calculations into DB triggers

migrations/20231110161954_base.sql

@@ -14,14 +14,6 @@ CREATE TABLE IF NOT EXISTS accounts(
     FOREIGN KEY (user) REFERENCES users(user_id)
 );
 
-CREATE TABLE IF NOT EXISTS account_snapshot(
-    account INTEGER,
-    datestamp DATE,
-    amount INT,
-    FOREIGN KEY (account) REFERENCES accounts(account_id),
-    PRIMARY KEY (account, datestamp)
-);
-
 CREATE TABLE IF NOT EXISTS categories (
     category_id INTEGER PRIMARY KEY AUTOINCREMENT,
     name TEXT,
@@ -41,13 +33,49 @@ CREATE TABLE IF NOT EXISTS transactions (
     transaction_id INTEGER PRIMARY KEY AUTOINCREMENT,
     account INTEGER,
     description TEXT,
-    transaction_timestamp DATETIME,
+    tx_date DATETIME,
     category INTEGER,
     amount INTEGER,
+    accumulated INTEGER DEFAULT 0,
+    tx_order INTEGER DEFAULT 0,
     hash TEXT,
     FOREIGN KEY (account) REFERENCES accounts(account_id),
     FOREIGN KEY (category) REFERENCES categories(category_id)
 );
 
-CREATE INDEX idx_transactions_ts ON transactions(account, transaction_timestamp);
-CREATE INDEX idx_transactions_hash ON transactions(hash);
+CREATE TRIGGER tx_insert AFTER INSERT ON transactions
+BEGIN
+    UPDATE transactions 
+    SET accumulated=old.acc+NEW.amount 
+    FROM (
+        SELECT COALESCE(max(accumulated), 0) AS acc
+        FROM transactions
+        WHERE date <= NEW.date
+        ORDER BY tx_order DESC
+        LIMIT 1
+    ) AS old 
+    WHERE id=NEW.id;
+
+    UPDATE transactions
+    SET tx_order=old.tx_order+1 FROM (
+        SELECT COALESCE(max(tx_order), 0) as tx_order
+        FROM tx WHERE date=NEW.date
+    ) AS old
+    WHERE id=NEW.id;
+
+    UPDATE transactions SET accumulated=calc.acc+NEW.accumulated FROM (
+        SELECT tx.id, (
+            SUM(amount) OVER (
+                ORDER BY date, tx_order
+                ROWS BETWEEN
+                UNBOUNDED PRECEDING
+                AND CURRENT ROW
+            )
+        ) acc
+        FROM transactions tx
+        WHERE date > NEW.date OR id=NEW.id;
+    )
+    WHERE transactions.id=calc.id;
+END;
+CREATE INDEX idx_transactions_ts ON transactions(account, tx_date);
+CREATE INDEX idx_transactions_hash ON transactions(hash);