Changes between Version 14 and Version 15 of Normalization

Timestamp:

12/26/25 23:15:11 (7 days ago)

Author:

211101

Comment:

--

Normalization

@@ -164 +164 @@
 
 R4.1 = R3.1 - { transaction_breakdown_id, transaction_id, transaction_account_id, spent_amount, earned_amount }
+
 R4.1 = ∅
 
@@ -169 +170 @@
 Проблем се транзитивните зависности, кои во 2NF сè уште постојат, на пример:
 - {transaction_id} → {tag_id} → {tag_name}
-- {transaction_account_id} → {user_id} → {user_name, email}
 
 Ова значи дека некои атрибути кои не се клучеви зависат од други атрибути кои исто така не се клучеви, што ја крши 3NF.
@@ -202 +202 @@
 || 3 || debit card || 3200 || 2 ||
 
-==== R5
+==== R3.2
 
 {transaction_id} → {transaction_name, amount, net_amount, date}
@@ -212 +212 @@
 || 3 || nail polish || -200 || -200 || 19:31:32 Sep 12 2025 ||
 
+====== Lossless join test
+
+R3:
+||= //transaction_id =||= //transaction_name =||= //amount =||= //net_amount =||= //date =||= //tag_id =||= //tag_name =||
+R3.2:
+||= //transaction_id =||= //transaction_name =||= //amount =||= //net_amount =||= //date =||
+
+R3 ∩ R3.2 = { transaction_id, transaction_name, amount, net_amount, date }
+
+transaction_id → R3.2
+
+R3 ∩ R3.2 → R3.2
+
+⇒ Декомпозицијата е lossless
+
+R3.3 = R3 - { transaction_id, transaction_name, amount, net_amount, date }
+
+==== R3.4
+
 {tag_id} → {tag_name}
 
@@ -220 +239 @@
 || 3 || beauty ||
 
+====== Lossless join test
+
+R3.3:
+||= //tag_id =||= //tag_name =||
+R3.4:
+||= //tag_id =||= //tag_name =||
+
+R3.3 ∩ R3.4 = { tag_id, tag_name }
+
+tag_id → R3.4
+
+R3.3 ∩ R3.4 → R3.4
+
+⇒ Декомпозицијата е lossless
+
+R3.5 = R3.3 - { tag_id, tag_name }
+
+R3.5 = ∅
+
 ==== R4
 
@@ -230 +268 @@
 || 3 || 3 || 3 || -200 || 0 ||
 
-==== R6
+==== R5
 
 {transaction_id, tag_id} → {}
@@ -323 +361 @@
 ⇒ Тривијално lossless
 
-==== 6
+==== 4
 TRANSACTION_BREAKDOWN