From 7971bc8635a56a6e63888ee0e2c6d002555de630 Mon Sep 17 00:00:00 2001
From: prachya <10935299+prachyboon@users.noreply.github.com>
Date: Sat, 9 Mar 2024 08:18:57 +0000
Subject: [PATCH] notes in learning

---
 .vscode/settings.json                                  |  1 -
 Chapter 2/Finding Duplicate Rows/Duplicate2.sql        |  2 +-
 .../Finding Inaccurate Data Values/CheckOrderTotal.sql |  6 +++---
 Chapter 2/Using Data Types/SelectCustomerOrdersSum.sql |  3 +--
 .../Filtering By Dates/WithCurrentDateMinus10years.sql |  3 ++-
 Chapter 4/Common SQL String Functions/Trim.sql         | 10 +++++-----
 6 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/.vscode/settings.json b/.vscode/settings.json
index 66874f2..eceb2a3 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -17,7 +17,6 @@
   "files.autoSave": "afterDelay",
   "screencastMode.onlyKeyboardShortcuts": true,
   "terminal.integrated.fontSize": 18,
-  "workbench.activityBar.visible": true,
   "workbench.colorTheme": "Visual Studio Dark",
   "workbench.fontAliasing": "antialiased",
   "workbench.statusBar.visible": true,
diff --git a/Chapter 2/Finding Duplicate Rows/Duplicate2.sql b/Chapter 2/Finding Duplicate Rows/Duplicate2.sql
index f70013a..dbe8d45 100644
--- a/Chapter 2/Finding Duplicate Rows/Duplicate2.sql	
+++ b/Chapter 2/Finding Duplicate Rows/Duplicate2.sql	
@@ -1,4 +1,4 @@
 SELECT FirstName, LastName, COUNT(1)
 FROM Customer
 GROUP BY FirstName, LastName
-HAVING COUNT(1) > 1
\ No newline at end of file
+HAVING COUNT(1) > 1 -- check duplicate
\ No newline at end of file
diff --git a/Chapter 2/Finding Inaccurate Data Values/CheckOrderTotal.sql b/Chapter 2/Finding Inaccurate Data Values/CheckOrderTotal.sql
index 64089b3..9f92eeb 100644
--- a/Chapter 2/Finding Inaccurate Data Values/CheckOrderTotal.sql	
+++ b/Chapter 2/Finding Inaccurate Data Values/CheckOrderTotal.sql	
@@ -1,8 +1,8 @@
 SELECT OrderItem.OrderId,
-  Orders.TotalDue,
-  SUM(Price * Quantity) as NewTotalDue
+  Orders.TotalDue, -- compare totalDue
+  SUM(Price * Quantity) as NewTotalDue -- with newTortalDue
 FROM OrderItem
   JOIN Product ON OrderItem.ProductID = Product.ProductID
   JOIN Orders ON OrderItem.OrderID = Orders.OrderID
 GROUP BY OrderItem.OrderId,
-  Orders.TotalDue
\ No newline at end of file
+  Orders.TotalDue;
\ No newline at end of file
diff --git a/Chapter 2/Using Data Types/SelectCustomerOrdersSum.sql b/Chapter 2/Using Data Types/SelectCustomerOrdersSum.sql
index 213dd72..d05674d 100644
--- a/Chapter 2/Using Data Types/SelectCustomerOrdersSum.sql	
+++ b/Chapter 2/Using Data Types/SelectCustomerOrdersSum.sql	
@@ -7,5 +7,4 @@ From Customer
 GROUP BY Customer.CustomerID,
   FirstName,
   LastName
-ORDER BY Sum(TotalDue) DESC
-LIMIT 10 -- Click on Run on active connection to run
\ No newline at end of file
+ORDER BY Sum(TotalDue) DESC -- Click on Run on active connection to run
\ No newline at end of file
diff --git a/Chapter 3/Filtering By Dates/WithCurrentDateMinus10years.sql b/Chapter 3/Filtering By Dates/WithCurrentDateMinus10years.sql
index 65470f9..1c04f93 100644
--- a/Chapter 3/Filtering By Dates/WithCurrentDateMinus10years.sql	
+++ b/Chapter 3/Filtering By Dates/WithCurrentDateMinus10years.sql	
@@ -1,3 +1,4 @@
 SELECT OrderID, CreationDate
 FROM Orders
-Where Year(CreationDate) > (Year(Now()) - 10);
\ No newline at end of file
+Where Year(CreationDate) > (Year(Now()) - 10); 
+-- more than past 10 years now 
\ No newline at end of file
diff --git a/Chapter 4/Common SQL String Functions/Trim.sql b/Chapter 4/Common SQL String Functions/Trim.sql
index 7b702ba..fec5bc0 100644
--- a/Chapter 4/Common SQL String Functions/Trim.sql	
+++ b/Chapter 4/Common SQL String Functions/Trim.sql	
@@ -1,5 +1,5 @@
-SELECT TRIM(
-    'M'
-    FROM ProductCode
-  ) AS TrimmedProductCode
-FROM Product
\ No newline at end of file
+SELECT TRIM('M'FROM ProductCode) AS TrimmedProductCode
+FROM Product;
+
+-- working only leading and trailing
+SELECT TRIM('0' FROM ProductCode) FROM Product;