diff --git a/Data Modification Language.sql b/Data Modification Language.sql
new file mode 100644
index 0000000..babebdc
--- /dev/null
+++ b/Data Modification Language.sql	
@@ -0,0 +1,340 @@
+-----------------Insertion-----------------------------Insertion to customer tables
+ INSERT INTO Customers (customer_id, name, email, address, phone)
+ VALUES ('C1', 'John Doe', 'johndoe@example.com', '123 Main St, Anytown, 
+USA', '123-456-7890');
+ INSERT INTO Customers (customer_id, name, email, address, phone)
+ VALUES ('C2', 'Jane Smith', 'janesmith@example.com', '456 Elm St, 
+Othertown, USA', '987-654-3210');
+ INSERT INTO Customers (customer_id, name, email, address, phone)
+ VALUES ('C3', 'Alice Johnson', 'alicejohnson@example.com', '789 Oak Ave, 
+Anothercity, USA', '456-789-1234');
+ INSERT INTO Customers (customer_id, name, email, address, phone)
+ VALUES ('C4', 'Bob Wilson', 'bobwilson@example.com', '321 Pine Rd, 
+Differenttown, USA', '789-123-4567');
+ INSERT INTO Customers (customer_id, name, email, address, phone)
+ VALUES ('C5', 'Sarah Davis', 'sarahdavis@example.com', '567 Cedar Ln, 
+Somewhere, USA', '234-567-8901');
+ INSERT INTO Customers (customer_id, name, email, address, phone)
+ VALUES ('C6', 'Michael Thompson', 'michaelthompson@example.com', '890 
+Walnut Ave, Elsewhere, USA', '678-901-2345');
+ INSERT INTO Customers (customer_id, name, email, address, phone)
+ VALUES ('C7', 'Emily Wilson', 'emilywilson@example.com', '432 Maple St, 
+Anytown, USA', '012-345-6789');
+ INSERT INTO Customers (customer_id, name, email, address, phone)
+ VALUES ('C8', 'David Lee', 'davidlee@example.com', '765 Birch Rd, 
+Othertown, USA', '901-234-5678');
+ INSERT INTO Customers (customer_id, name, email, address, phone)
+ VALUES ('C9', 'Jennifer Miller', 'jennifermiller@example.com', '109 Pine 
+Ln, Anothercity, USA', '345-678-9012');
+ INSERT INTO Customers (customer_id, name, email, address, phone)
+ VALUES ('C10', 'Ryan Harris', 'ryanharris@example.com', '876 Oak St, 
+Differenttown, USA', '678-901-2345');---Insertion into products table
+ INSERT INTO Products (product_id, name, price, description)
+ VALUES ('P1', 'Product A', 10.99, 'Description for Product A');
+ INSERT INTO Products (product_id, name, price, description)
+ VALUES ('P2', 'Product B', 19.99, 'Description for Product B');
+ INSERT INTO Products (product_id, name, price, description)
+VALUES ('P3', 'Product C', 8.49, 'Description for Product C');
+ INSERT INTO Products (product_id, name, price, description)
+ VALUES ('P4', 'Product D', 14.99, 'Description for Product D');
+ INSERT INTO Products (product_id, name, price, description)
+ VALUES ('P5', 'Product E', 6.99, 'Description for Product E');
+ INSERT INTO Products (product_id, name, price, description)
+ VALUES ('P6', 'Product F', 12.49, 'Description for Product F');
+ INSERT INTO Products (product_id, name, price, description)
+ VALUES ('P7', 'Product G', 9.99, 'Description for Product G');
+ INSERT INTO Products (product_id, name, price, description)
+ VALUES ('P8', 'Product H', 17.99, 'Description for Product H');
+ INSERT INTO Products (product_id, name, price, description)
+ VALUES ('P9', 'Product I', 5.99, 'Description for Product I');
+ INSERT INTO Products (product_id, name, price, description)
+ VALUES ('P10', 'Product J', 11.99, 'Description for Product J');-- Insert into order table
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O1', 'C1', SYSDATE, 50.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O2', 'C2', SYSDATE, 30.49);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O3', 'C3', SYSDATE, 25.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O4', 'C4', SYSDATE, 40.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O5', 'C5', SYSDATE, 35.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O6', 'C6', SYSDATE, 45.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O7', 'C7', SYSDATE, 20.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O8', 'C8', SYSDATE, 15.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O9', 'C9', SYSDATE, 55.99);
+INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O10', 'C10', SYSDATE, 60.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O11', 'C1', SYSDATE, 75.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O12', 'C1', SYSDATE, 62.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O13', 'C2', SYSDATE, 45.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O14', 'C3', SYSDATE, 28.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O15', 'C3', SYSDATE, 35.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O16', 'C5', SYSDATE, 39.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O17', 'C6', SYSDATE, 52.99);
+ INSERT INTO Orders (order_id, customer_id, order_date, total_amount)
+ VALUES ('O18', 'C6', SYSDATE, 67.99);-- Insert data into Order_Items table
+ INSERT INTO Order_Items (order_item_id, order_id, product_id, customer_id, 
+quantity)
+ VALUES ('OI4', 'O3', 'P4', 'C3', 4);
+ INSERT INTO Order_Items (order_item_id, order_id, product_id, customer_id, 
+quantity)
+ VALUES ('OI5', 'O4', 'P5', 'C4', 2);
+ INSERT INTO Order_Items (order_item_id, order_id, product_id, customer_id, 
+quantity)
+ VALUES ('OI6', 'O5', 'P6', 'C5', 1);
+ INSERT INTO Order_Items (order_item_id, order_id, product_id, customer_id, 
+quantity)
+VALUES ('OI7', 'O6', 'P7', 'C6', 3);
+ INSERT INTO Order_Items (order_item_id, order_id, product_id, customer_id, 
+quantity)
+ VALUES ('OI8', 'O7', 'P8', 'C7', 2);
+ INSERT INTO Order_Items (order_item_id, order_id, product_id, customer_id, 
+quantity)
+ VALUES ('OI9', 'O8', 'P9', 'C8', 1);
+ INSERT INTO Order_Items (order_item_id, order_id, product_id, customer_id, 
+quantity)
+ VALUES ('OI10', 'O9', 'P10', 'C9', 3);
+ INSERT INTO Order_Items (order_item_id, order_id, product_id, customer_id, 
+quantity)
+ VALUES ('OI1', 'O1', 'P1', 'C1', 2);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI55', 'O18', 'P5', 3, 14.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI56', 'O18', 'P6', 2, 24.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI3', 'O2', 'P3', 3, 12.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI4', 'O2', 'P4', 2, 8.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI5', 'O3', 'P5', 1, 14.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI7', 'O3', 'P7', 1, 17.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI8', 'O4', 'P2', 2, 19.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI9', 'O4', 'P5', 3, 14.99);
+INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI10', 'O4', 'P9', 1, 8.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI11', 'O5', 'P3', 2, 12.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI12', 'O5', 'P4', 1, 15.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI13', 'O5', 'P8', 1, 10.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI14', 'O6', 'P1', 2, 9.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI15', 'O6', 'P2', 1, 19.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI16', 'O6', 'P5', 3, 14.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI17', 'O7', 'P3', 2, 12.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI18', 'O7', 'P4', 1, 15.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI19', 'O7', 'P6', 1, 24.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI20', 'O8', 'P1', 1, 9.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI21', 'O8', 'P3', 3, 12.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI22', 'O8', 'P8', 2, 10.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+VALUES ('OI23', 'O9', 'P2', 2, 19.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI24', 'O9', 'P4', 1, 15.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI25', 'O9', 'P7', 2, 17.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI26', 'O10', 'P1', 3, 9.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI27', 'O10', 'P3', 1, 12.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI28', 'O10', 'P5', 2, 14.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI29', 'O11', 'P2', 1, 19.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI30', 'O11', 'P4', 2, 15.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI31', 'O11', 'P8', 1, 10.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI32', 'O12', 'P1', 3, 9.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI33', 'O12', 'P2', 2, 19.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI34', 'O12', 'P6', 1, 24.99);
+INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI35', 'O13', 'P3', 2, 12.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI36', 'O13', 'P5', 1, 14.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI37', 'O13', 'P9', 2, 8.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI38', 'O14', 'P2', 1, 19.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI39', 'O14', 'P4', 2, 15.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI40', 'O14', 'P7', 1, 17.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI41', 'O15', 'P1', 3, 9.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI42', 'O15', 'P3', 1, 12.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI43', 'O15', 'P5', 2, 14.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI44', 'O16', 'P4', 1, 15.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI45', 'O16', 'P6', 2, 24.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI46', 'O17', 'P2', 1, 19.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI47', 'O17', 'P3', 3, 12.99);
+INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI48', 'O17', 'P5', 2, 14.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI49', 'O17', 'P7', 1, 17.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI50', 'O18', 'P1', 1, 9.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI51', 'O18', 'P4', 2, 15.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI52', 'O18', 'P6', 1, 24.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI53', 'O18', 'P8', 3, 11.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI54', 'O18', 'P10', 2, 9.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI55', 'O18', 'P9', 1, 8.99);
+ INSERT INTO order_items (order_item_id, order_id, product_id, quantity, 
+unit_price)
+ VALUES ('OI56', 'O18', 'P3', 2, 12.99);-------------------------------------Aggregate Function---------------------------Calculate the total number of customers:
+ SELECT COUNT(*) AS total_customers FROM Customers;--Calculate the average price of products:
+ SELECT AVG(price) AS average_price FROM Products;--Find the maximum price among all products:
+ SELECT MAX(price) AS max_price FROM Products;--Determine the minimum quantity ordered in Order_Items:
+ SELECT MIN(quantity) AS min_quantity FROM Order_Items;--Calculate the number of prouducts in each order:
+ SELECT order_id, count(*) as number_of_products
+FROM Order_Items
+ GROUP BY order_id;----using group by and having--------
+SELECT customer_id, COUNT(*) as order_count
+ FROM Orders
+ GROUP BY customer_id
+ HAVING COUNT(*) > 1;--Calculate the total amount for each order:
+ SELECT order_id, SUM(quantity * unit_price) AS total_amount
+ FROM Order_Items
+ GROUP BY order_id;---------------------------Join------------------------------------Inner Join:
+ SELECT *
+ FROM Customers
+ INNER JOIN Orders ON Customers.customer_id = Orders.customer_id;--Left Join:
+ SELECT Customers.customer_id, Customers.name, Orders.order_id
+ FROM Customers
+ LEFT JOIN Orders ON Customers.customer_id = Orders.customer_id;--Right Join:
+ SELECT Customers.customer_id, Customers.name, Orders.order_id
+ FROM Customers
+ RIGHT JOIN Orders ON Customers.customer_id = Orders.customer_id;--Full Outer Join:
+ SELECT Customers.customer_id, Customers.name, Orders.order_id
+ FROM Customers
+ FULL OUTER JOIN Orders ON Customers.customer_id = Orders.customer_id;----------------------------Union, intercept, except---------------------------
+SELECT order_id FROM Orders
+ UNION
+ SELECT customer_id FROM Customers;
+ SELECT order_id FROM Orders
+ INTERSECT
+ SELECT customer_id FROM Customers;----customers who brought the product 'P1' using subquery
+select customer_id from orders where order_id in (select order_id from 
+order_items where product_id in (select product_id from products where 
+product_id = 'P1'));----customers who brought the product 'P1' using join
+ select customer_id from orders join (order_items join products on 
+order_items.product_id = products.product_id) using(order_id) where 
+products.product_id = 'P1';-----customer name who brought the product 'P1'
+ select name from customers where customer_id in (select customer_id from 
+orders join (order_items join products on order_items.product_id = 
+products.product_id) using(order_id) where products.product_id = 'P1'
+ );-----------------------With statement to find max priced product
+ with max_price(val) as (select max(price) from products)
+ select * from products, max_price where products.price = max_price.val;------------------------set membership function-------------
+select * from customers where customer_id = 'C1' and name in (select name 
+from customers where name like '%John%');
+ select * from customers where customer_id = 'C1' or name in (select name 
+from customers where name like '%John%');
+ select * from customers where customer_id = 'C1' and name not in (select 
+name from customers where name like '%John%');-----------------------some, all, exist, unique--------------
+select * from products where price > some (select price from products 
+where price > 10);
+ select * from products where price > all (select price from products where 
+price < 10);
+ select * from orders where total_amount > 50 and exists(select Customer_id 
+from orders);
+ select unique customer_id from orders where total_amount > 50;----------------------string operations------------------
+select name from customers where name like '________';
+ select name from customers where name like '%John%';---------------------Views-----------------------
+create view show_name as select name from customers;
+ select name from show_name;---views using other views
+ create view particular_name as select name from show_name where name like 
+'________';
+ select name from particular_name;
\ No newline at end of file
diff --git a/Data definition language.sql b/Data definition language.sql
new file mode 100644
index 0000000..83530e9
--- /dev/null
+++ b/Data definition language.sql	
@@ -0,0 +1,42 @@
+drop table customers;
+ drop table products;
+ drop table order_items;
+ drop table orders;
+ CREATE TABLE Customers (
+ customer_id VARCHAR2(20) PRIMARY KEY,
+ name VARCHAR2(100) NOT NULL,
+ email VARCHAR2(100) UNIQUE NOT NULL,
+ address VARCHAR2(200),
+ phone VARCHAR2(20)
+ );
+ CREATE TABLE Products (
+ product_id VARCHAR2(20) PRIMARY KEY,
+ name VARCHAR2(100) NOT NULL,
+ price NUMBER,
+ description VARCHAR2(200)
+ );
+ CREATE TABLE Orders (
+ order_id VARCHAR2(20) PRIMARY KEY,
+ customer_id VARCHAR2(20),
+ order_date DATE,
+ total_amount NUMBER check (total_amount > 0),
+ CONSTRAINT fk_orders_customers
+ FOREIGN KEY (customer_id) REFERENCES Customers (customer_id) on delete 
+cascade
+ );
+ CREATE TABLE Order_Items (
+ order_item_id VARCHAR2(20) PRIMARY KEY,
+ order_id VARCHAR2(20),
+ product_id VARCHAR2(20),
+ quantity NUMBER check (quantity > 0),
+ unit_price NUMBER check (unit_price > 0),
+ CONSTRAINT fk_order_items_orders
+ FOREIGN KEY (order_id) REFERENCES Orders (order_id),
+ CONSTRAINT fk_order_items_products
+ FOREIGN KEY (product_id) REFERENCES Products (product_id)
+ );
+ ALTER TABLE Customers
+ ADD age NUMBER;
+ alter table Customers modify age varchar(20);
+ alter table Customers rename column age to customer_age;
+ ALTER TABLE Customers Drop column customer_age;
\ No newline at end of file
diff --git a/ER diagram .jpg b/ER diagram .jpg
new file mode 100644
index 0000000..7a8c03d
Binary files /dev/null and b/ER diagram .jpg differ
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..5857202
--- /dev/null
+++ b/README.md
@@ -0,0 +1,2 @@
+# database-project-1907032Arif
+Database Project Submission by 1907032Arif
diff --git a/plsql and trigger.sql b/plsql and trigger.sql
new file mode 100644
index 0000000..1549fb9
--- /dev/null
+++ b/plsql and trigger.sql	
@@ -0,0 +1,175 @@
+  
+set serveroutput on;  ---procedure using IN, OUT and IN OUT parameter  
+create or replace procedure calculate_order_total(  
+p_order_id IN Orders.order_id%type,  
+p_total_amount OUT Orders.total_amount%type,  
+p_discount_rate IN OUT NUMBER  
+)  
+Is  
+Begin  
+select total_amount into p_total_amount from Orders where order_id = p_order_id;  
+p_total_amount := p_total_amount - p_total_amount*p_discount_rate;  
+p_discount_rate := p_discount_rate + 0.1;  
+END;  
+/  
+  
+declare   
+p_order_id orders.order_id%type := ’O4’;  
+p_total_amount orders.total_amount%type;  
+p_discount_rate number := 0.2;  
+begin  
+calculate_order_total(p_order_id, p_total_amount, p_discount_rate);  
+dbms_output.put_line('Order Id: '|| p_order_id || ', Order amount: ' || p_total_amount || ', Discount Rate: ' ||
+ p_discount_rate);  
+end;  
+/  
+  
+  
+  
+  -- Using varray, loop, and cursor  
+  -- Declare a VARRAY type  
+CREATE OR REPLACE TYPE product_list IS VARRAY(10) OF VARCHAR2(100);  
+/  -- Declare a procedure to populate VARRAY using cursor  
+CREATE OR REPLACE PROCEDURE get_customer_products(p_products_list OUT product_list) IS  
+  -- Declare a cursor  
+  CURSOR c_products IS  
+    SELECT name FROM products;  
+   -- Variable to store the fetched row  
+  v_product_name products.name%TYPE;  
+BEGIN  
+ -- Open the cursor  
+  OPEN c_products;  
+   -- Initialize the VARRAY  
+  p_products_list := product_list();  
+     
+  -- Fetch and populate VARRAY with each row  
+  LOOP  
+    -- Fetch the next row into the variable  
+    FETCH c_products INTO v_product_name;  
+      
+    -- Exit the loop if no more rows  
+    EXIT WHEN c_products%NOTFOUND;  
+      
+      -- Add the fetched value to the VARRAY  
+    p_products_list.EXTEND;  
+    p_products_list(p_products_list.COUNT) := v_product_name;  
+  END LOOP;  
+   -- Close the cursor   
+  CLOSE c_products;  
+END;  
+/  
+  
+   
+ DECLARE  
+ v_products product_list;  
+ BEGIN  
+    get_customer_products(v_products);  
+      
+    for i IN 1 .. v_products.COUNT LOOP  
+        DBMS_OUTPUT.PUT_LINE('Product: ' || v_products(i));  
+    END LOOP;  
+          
+ END;  
+ /  
+   
+  
+   
+ ----Showing rowcount, rowfound, cursor  
+ create or replace procedure process_orders_sec  
+is  
+CURSOR c_order IS  
+    select order_id, customer_id, order_date, total_amount from orders;  
+    v_order_row c_order%rowtype;  
+    v_row_count integer:=0;  
+      
+ begin  
+    open c_order;  
+      
+    loop  
+        fetch c_order into v_order_row;  
+        exit when c_order%notfound;  
+          
+        dbms_output.put_line('order_id: ' || v_order_row.order_id||', Customer_ID: '||v_order_row.customer_id||', Order Date: '||v_order_row.order_date||', Total amount: '||v_order_row.total_amount);  
+          
+        v_row_count := v_row_count+1;  
+    end loop;  
+     
+     dbms_output.put_line('Total orders processed: '||c_order%rowcount);  
+     dbms_output.put_line('Total orders processed: '||v_row_count);  
+     CLOSE c_order;  
+end;  
+/  
+  
+BEGIN  
+  process_orders_sec;  
+END;  
+/  -----use if elseif else ------  
+create or replace procedure check_order_total(p_id IN ORDERS.ORDER_ID%type) is  
+amount ORDERS.TOTAL_AMOUNT%type;  
+begin  
+select total_amount into amount from ORDERS where order_id = p_id;  
+IF amount > 1000 then  
+dbms_output.put_line('Order ' || p_id || 'is large');  
+ELSIF amount <1000 AND amount>500 then  
+dbms_output.put_line('Order ' || p_id || 'is medium');  
+ELSE   
+dbms_output.put_line('Order ' || p_id || 'is small');  
+end if;  
+end;  
+/  
+declare  
+p_id ORDERS.ORDER_ID%type := ’O4’;  
+begin  
+check_order_total(p_id);  
+end;  
+/  ----a function-----  
+create or replace function calculate_total(p_quantity in number, p_unit_price in number)   
+return number is  
+v_total_price number;  
+begin  
+v_total_price := p_quantity*p_unit_price;  
+return v_total_price;  
+end;  
+/  ------------function in a query-----------  
+SELECT order_id,  calculate_total(2, 3) AS total_price  
+FROM Orders;  
+show errors procedure check_order_total;  
+
+
+
+
+
+
+----------Trigger--------
+
+CREATE OR REPLACE TRIGGER update_customer_info_trigger
+AFTER UPDATE ON Orders
+FOR EACH ROW
+BEGIN
+  -- Update the customer's phone number in the Customers table
+  UPDATE Customers
+  SET phone = :NEW.phone
+  WHERE customer_id = :NEW.customer_id;
+END;
+/
+
+
+CREATE OR REPLACE TRIGGER insert_into_order_items_trigger
+AFTER INSERT ON Orders
+FOR EACH ROW
+BEGIN
+  -- Insert a row into Order_Items
+  INSERT INTO Order_Items (order_item_id, order_id, product_id, quantity, unit_price)
+  VALUES (:NEW.order_item_id, :NEW.order_id, :NEW.product_id, :NEW.quantity, :NEW.unit_price);
+END;
+/
+
+CREATE OR REPLACE TRIGGER delete_from_order_items_trigger
+AFTER DELETE ON Orders
+FOR EACH ROW
+BEGIN
+  -- Delete rows from Order_Items
+  DELETE FROM Order_Items
+  WHERE order_id = :OLD.order_id;
+END;
+/
\ No newline at end of file