Farhana week 3

week-1/mandatory/2-classes-db/task.md

@@ -7,6 +7,58 @@ Below you will find a set of tasks for you to complete to consolidate and extend
 To submit this homework write the correct commands for each question here:
 
 ```sql
+1. SELECT * from room_types WHERE def_rate > 100;
+
+2. SELECT * from reservations WHERE checkin_date BETWEEN '2020-09-01' AND'2020-09-30' AND (checkout_date - checkin_date ) > 3;
+
+3. SELECT * from customers WHERE city LIKE 'M%';
+
+4. INSERT into room_types (room_type,def_rate) VALUES ('PENTHOUSE',185.00);
+
+5. INSERT into rooms (room_no, rate, room_type) VALUES
+   (501,185.00,'PENTHOUSE'),
+   (502,185.00,'PENTHOUSE');
+
+6. INSERT into rooms (room_no, rate, room_type) VALUES
+   (503,143.00,'PREMIER PLUS');
+
+7. SELECT count(id) from reservations
+   WHERE checkin_date >= '2020-08-01'
+   AND checkout_date <= '2020-08-31';
+
+8. SELECT SUM(checkout_date - checkin_date) from
+   reservations WHERE room_no between 201 AND 299;
+
+9. SELECT COUNT(*) from invoices
+   WHERE total > 300.00;
+
+   *Grand Total* 
+   SELECT SUM(total) from invoices
+   WHERE total > 300.00;
+
+   *Average*
+   SELECT AVG(total) from invoices 
+   WHERE total > 300.00;
+
+10. SELECT SUM(checkout_date - checkin_date) from reservations
+    WHERE room_no between 101 AND 112; 
+    (54)
+
+    SELECT SUM(checkout_date - checkin_date) from reservations
+    WHERE room_no between 201 AND 212;
+    (63)
+
+    SELECT SUM(checkout_date - checkin_date) from reservations
+    WHERE room_no between 301 AND 312;
+    (46)
+
+    SELECT SUM(checkout_date - checkin_date) from reservations
+    WHERE room_no between 401 AND 412;
+    (40)   
+
+    SELECT SUM(checkout_date - checkin_date) from reservations
+    WHERE room_no between 501 AND 512; 
+    (none)
 
 
 ```

week-2/mandatory/2-ecommerce-db/task.md

@@ -8,6 +8,36 @@ Below you will find a set of tasks for you to complete to set up a database for
 
 To submit this homework write the correct commands for each question here:
 ```sql
+1. select name, address from customers where country ='United States';
+
+2. select name from customers order by name asc;
+
+3.select * from products where product_name like '%socks%';
+
+4. select p.product_name, pa.* from products p join product_availability pa on (p.id = pa.prod_id) where pa.unit_price > 100;
+
+5. select p.product_name, pa.unit_price from products p join product_availability pa on (p.id = pa.prod_id) order by pa.unit_price limit 5;
+
+6. select p.product_name, pa.unit_price, s.suuplier_name from products p join product_availability pa on (p.id = pa.prod_id) join suppliers s on (pa.supp_id = s.id);
+
+7.select p.product_name , s.supplier_name from products p join product_availability pa on (p.id = pa.prod_id) join suppliers s on (pa.supp_id = s.id) where s.country ='United Kingdom';
+
+8. select o.id, o.order_reference, o.order_date, (oi.quantity * pa.unit_price) as total_cost from orders o join order_items oi on (o.id =oi.order_id) join product_availability pa on (oi.product_id = pa.prod_id) where o.customer_id = 1;
+
+9. select * from order_items oi join orders o on (oi.order_id = o.id) join customers c on (o.custmer_id = c.id) where c.name ='Hope Crosby';
+
+10. select p.product_name, pa.unit_price, oi.quantity from products p join product_availability pa on (p.id = pa.prod_id) join order_items oi on (pa.prod_id = oi.product_id) join orders o on (oi.order_id = o.id) where o.order_reference = 'ORD006';
+
+11. select c.name, p.product_name, o.order_reference, o.order_date, s.supplier_name, oi.quantity from customers c join orders o on (c.id = o.customers_id) join order_items oi on (o.id = oi.order_id) join suppliers s on (oi.supplier_id = s.id) join product_availability pa on (s.id = pa.supp.id) join products p on (pa.prod_id = p.id);
+
+12. select distinct c.name from customers c join orders o on (c.id = o.customer_id) join order_items oi on (o.id = oi.order_id) join suppliers s on (oi.supplier_id = s.id) where s.country ='China';
+
+13. select c.name, o.order_reference, o.order_date, (oi.quantity * pa.unit_price) as total_cost from customers c join orders o on (c.id = o.customer_id) join order_items oi on (o.id = oi.order_id) join product_availalbility pa on (oi.product_id = pa.prod_id) order by total_cost desc;
+
+
+
+
+
 
 
 ```

week-2/mandatory/3-api/server.js

@@ -0,0 +1,43 @@
+const express = require("express");
+const app = express();
+
+app.listen(3000, function(){
+    console.log("Server is listening on port 3000. Ready to accept requests! ")
+});
+
+const {Pool} = require ('pg');
+
+const db = new Pool({
+    user: 'farhana',
+    host:'localhost',
+    database: 'cyf_ecommerce',
+    pasword: '',
+    port: 5432
+});
+
+//get all customers
+
+app.get("/customers", function(req, res){
+    db.query('SELECT id, name, address,city, country FROM  customers',
+         (error, result) => {
+             res.json(result.rows);
+         });
+});
+
+//get all suppliers
+
+app.get("/suppliers", function(re,res){
+    db.query('SELECT id, supplier_name, country FROM suppliers',
+       (error, result) => {
+           res.json(result.rows);
+       });
+});
+
+// get product names, their prices and suppliers
+app.get("/products", function(req, res){
+    db.query('SELECT p.product_name, pa.unit_price, s.supplier_name FROM products p JOIN product_availability pa ON (p.id = pa.prod_id) JOIN suppliers s ON(pa.supp_id = s.id)',
+    (error, result) => {
+        res.json(result.rows);
+    });
+});
+

week-3/mandatory/2-api/server.js

@@ -0,0 +1,243 @@
+const express = require('express');
+const bodyParser = require('body-parser');
+const app = express();
+// app.use(bodyParser.urlencoded({ extended: true }));
+app.use(bodyParser.json());
+
+
+
+app.listen(3000, function(){
+    console.log("Server is listening on port 3000. Ready to accept requests!");
+} );
+
+const {Pool} = require ('pg');
+
+const db = new Pool({
+    user: 'farhana',
+    host:'localhost',
+    database: 'cyf_ecommerce',
+    pasword: '',
+    port: 5432
+});
+
+// // get product names, their prices and suppliers + query paramaters
+app.get("/products", function(req, res){
+    let name = req.query.name;
+
+      if(name === undefined){
+        db.query('SELECT p.product_name, pa.unit_price, s.supplier_name FROM products p JOIN product_availability pa ON (p.id = pa.prod_id) JOIN suppliers s ON(pa.supp_id = s.id)',
+        (error, result) => {
+            if(error === undefined){
+                res.json(result.rows);
+            } else{
+                res.status(400).send("Bad request "+ error);
+            }
+
+        });
+      } else{
+        let newName = name.toLowerCase();
+          db.query("SELECT * FROM products WHERE Lower(product_name) LIKE '%'||$1||'%'",[newName], (error, result)=>{
+              if(error === undefined){
+                res.json(result.rows);
+              } else{
+                  res.status(400).send("Bad request " + error);
+              }
+
+          });
+      }
+
+});
+
+//get customer by ID
+app.get("/customers/:customerid", function(req,res){
+    const customerId = parseInt(req.params.customerid);
+    if(customerId !== undefined){
+        db.query("SELECT * from customers WHERE id =$1",[customerId], (error, result) =>{
+            if(error === undefined){
+                res.json(result.rows);
+            } else{
+                res.status(400).send("Bad Request " + error );
+            }
+
+        });
+
+
+    } else{
+       res.send("Customer doesnt exist");       
+
+    }
+
+});
+
+    //get all customers
+
+app.get("/customers", function(req, res){
+    db.query('SELECT id, name, address,city, country FROM  customers',
+         (error, result) => {
+             if(error === undefined){
+                res.json(result.rows);
+             } else{
+                 res.status(400).send("Bad Request "+ error);
+             }
+
+         });
+});
+
+//POST new customer
+
+app.post("/customers", function(req,res){
+    const newName = req.body.name;
+    const newAddress = req.body.address;
+    const newCity = req.body.city
+    const newCountry = req.body.country;
+
+    db.query("INSERT INTO customers (name,address,city,country) VALUES ($1,$2,$3,$4) returning id",
+     [newName,newAddress,newCity,newCountry], (error, result)=>{
+         if(error == undefined){
+             res.send("New Customer Added" + result.rows[0].id);
+         }else {
+             res.status(400).send("Bad request" + error);
+             console.log(error);
+         }
+
+
+     });
+});    
+
+
+//add new product
+
+app.post("/products", function(req,res){
+    const newName = req.body.name;
+
+    db.query("INSERT INTO products (product_name) VALUES ($1) returning id",
+     [newName], (error, result)=>{
+         if(error == undefined){
+             res.send("New Product Added" + result.rows[0].id);
+         }else {
+             res.status(400).send("Bad request" + error);
+             console.log(error);
+         }         
+
+     });
+});    
+
+
+//Post product availability
+app.post("/availability", function(req,res){
+    const newProdId = req.body.prodId;
+    const newSuppId = req.body.suppId;
+    const newUnitPrice = req.body.unitPrice;
+
+
+    if(newUnitPrice > 0){
+        db.query("SELECT 1 FROM products WHERE id = $1",[newProdId], (error, result)=>{
+        if(result.rowCount < 0){
+            res.status(400).send("Product doesn't exist");
+
+        } else{
+
+            db.query("INSERT INTO product_availability (prod_id, unit_price) VALUES ($2,$3)",[newProdId, newUnitPrice], (error)=>{
+                db.query("SELECT 1 FROM suppliers WHERE id = $4",[newSuppId], (error,result)=>{
+                    if(result.rowCount < 0){
+                        res.status(400).send("Supplier doesn't exist");
+                    }else{
+                        db.query("INSERT INTO product_availability (supp_id) VALUES ($5)",[newSuppId], (error)=>{
+                            res.send("Product info added");
+                        })
+                    }
+                })
+            });
+        }
+    });
+    }else{
+        res.send("Enter a positive value");
+    }
+});
+
+//customers/:customerId/orders
+app.post("/customers/:id/orders", function(req,res){
+    const customerId = req.params.id;
+    const orderDate = req.body.orderDate;
+    const orderReference = req.body.orderReference;
+
+    db.query("SELECT 1 FROM customers WHERE id = $1",[customerId], (error, result)=>{
+        if(error == undefined){
+            if(result.rowCount < 0){
+                res.send("Customer doesn't exist");
+            } else{
+                db.query("INSERT INTO orders (order_date, order_reference, customer_id)"+
+                "VALUES ($2,$3,$1)",[orderDate, orderReference, customerId],(error)=>{
+                    if(error === undefined){
+                        res.send("New order added");
+                    }else{
+                        res.status(400).send("Bad request" + error);
+                        console.log(error);
+                    }
+
+                });
+            }
+        }else{
+            res.status(400).send("Bad request" + error);
+            console.log(error);
+        }
+    })
+
+})
+
+app.put("/customers/:id", function (req, res){
+    const customerId = req.params.id;
+    const newName = req.body.name;
+    const newAddress = req.body.address;
+    const newCity = req.body.city;
+    const newCountry = req.body.country;
+
+    db.query("UPDATE customers SET name=$2, address = $3, city = $4, country = $5 WHERE id=$1",
+            [customerId, newName, newAddress, newCity, newCountry], (error)=>{
+                if(error == undefined){
+                    res.send(`Customer ${customerId} updated!`);
+                } else{
+                    console.log(error);
+                    res.status(500).send("Bad Request");
+
+                }
+            });
+
+});
+
+app.delete("/orders/:orderId", function(req,res){
+    const orderId = req.params.orderId;
+
+    db.query("DELETE FROM orders WHERE id = $1",[orderId], (error)=>{
+        if(error==undefined){
+            res.send(`Order ${orderId} is deleted!`);
+        }else{
+            res.status(400).send("Bad Request " + error);
+        }
+    });
+});
+
+//delete an existing customer only if this customer doesn't have orders.
+app.delete("/customers/:id", function(req,res){
+    const customerId = req.params.id;
+    db.query("SELECT 1 from orders WHERE customer_id = $1",[customerId], (error, result)=>{
+        if(error == undefined){
+            if(result.rowCount === 0){
+                db.query("DELETE from customers WHERE id = $1",[customerId], (error)=>{
+                    if(error == undefined){
+                        res.send(`Customer ${customerId} deleted`)
+                    }else{
+                        res.status(400).send("Bad request " + error);
+                        console.log(error)
+                    }
+                })
+            }else{
+                res.send(`Customer ${customerId} has order pending`);
+            }
+        }else{
+            res.status(400).send("Bad Request " + error);
+            console.log(error);
+        }
+    });
+});
+