Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly
Sign up
Appearance settings

Commit 16ca273

Browse files
Update readme.md
1 parent c33fa4f commit 16ca273

File tree

1 file changed

+223
-0
lines changed
  • LeetCode SQL 50 Solution/prosnal_database

1 file changed

+223
-0
lines changed
Lines changed: 223 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,223 @@
1+
Below is a well-structured `README.md` that documents the database schema, sample data, and queries for the provided SQL code. This file can be added to your repository for clarity and organization.
2+
3+
```md
4+
# Prosnal Database Example
5+
6+
This repository contains SQL scripts for creating and populating a sample database called `prosnal_database`. The database includes multiple tables and queries demonstrating joins and calculations. The following sections describe the database schema, sample data insertion, and example queries.
7+
8+
---
9+
10+
## Database and Tables
11+
12+
### 1. Create and Use Database
13+
```sql
14+
CREATE DATABASE IF NOT EXISTS prosnal_database;
15+
USE prosnal_database;
16+
```
17+
- This command creates the database `prosnal_database` if it does not exist and sets it as the current working database.
18+
19+
---
20+
21+
### 2. Employees Table
22+
```sql
23+
CREATE TABLE IF NOT EXISTS Employees (
24+
Id INT,
25+
Name VARCHAR(255),
26+
Salary INT,
27+
Department VARCHAR(255)
28+
);
29+
```
30+
- **Description:**
31+
Contains employee information such as `Id`, `Name`, `Salary`, and `Department`.
32+
33+
#### Sample Data:
34+
```sql
35+
INSERT INTO Employees (Id, Name, Salary, Department)
36+
VALUES (1, 'John Doe', 50000, 'HR'),
37+
(2, 'Jane Smith', 60000, 'Finance'),
38+
(3, 'Mike Johnson', 70000, 'IT'),
39+
(4, 'Sarah Black', 60000, 'Finance'),
40+
(5, 'David White', 70000, 'IT');
41+
```
42+
43+
---
44+
45+
### 3. Projects Table
46+
```sql
47+
CREATE TABLE IF NOT EXISTS Projects (
48+
Id INT,
49+
Name VARCHAR(255),
50+
Department VARCHAR(255)
51+
);
52+
```
53+
- **Description:**
54+
Contains project details including project `Id`, `Name`, and the corresponding `Department`.
55+
56+
#### Sample Data:
57+
```sql
58+
INSERT INTO Projects (Id, Name, Department)
59+
VALUES (1, 'Project A', 'IT'),
60+
(2, 'Project B', 'Finance'),
61+
(3, 'Project C', 'IT');
62+
```
63+
64+
---
65+
66+
### 4. EmployeeProjects Table
67+
```sql
68+
CREATE TABLE IF NOT EXISTS EmployeeProjects (
69+
EmployeeId INT,
70+
ProjectId INT
71+
);
72+
```
73+
- **Description:**
74+
Associates employees with projects.
75+
76+
#### Sample Data:
77+
```sql
78+
INSERT INTO EmployeeProjects (EmployeeId, ProjectId)
79+
VALUES (1, 1),
80+
(1, 2),
81+
(2, 1),
82+
(3, 1),
83+
(3, 3),
84+
(4, 2),
85+
(5, 1);
86+
```
87+
88+
---
89+
90+
### 5. Users and Sessions Tables
91+
#### Users Table
92+
```sql
93+
CREATE TABLE users (
94+
id INT PRIMARY KEY,
95+
name VARCHAR(50),
96+
email VARCHAR(100)
97+
);
98+
```
99+
- **Description:**
100+
Contains user information with unique `id`, `name`, and `email`.
101+
102+
#### Sample Data:
103+
```sql
104+
INSERT INTO users (id, name, email)
105+
VALUES (1, 'John Doe', 'john.doe@example.com'),
106+
(2, 'Jane Smith', 'antima@example.com');
107+
```
108+
109+
#### Sessions Table
110+
```sql
111+
CREATE TABLE sessions (
112+
id INT PRIMARY KEY,
113+
user_id INT,
114+
session_date DATE
115+
);
116+
```
117+
- **Description:**
118+
Records session data with session `id`, associated `user_id`, and the `session_date`.
119+
120+
#### Sample Data:
121+
```sql
122+
INSERT INTO sessions (id, user_id, session_date)
123+
VALUES (1, 1, '2022年01月01日'),
124+
(2, 1, '2022年01月02日'),
125+
(3, 2, '2022年01月03日');
126+
```
127+
128+
---
129+
130+
### 6. Products and Orders Tables
131+
#### Products Table
132+
```sql
133+
CREATE TABLE IF NOT EXISTS products (
134+
id INT PRIMARY KEY,
135+
name VARCHAR(50),
136+
price DECIMAL(10, 2)
137+
);
138+
```
139+
- **Description:**
140+
Contains product details such as `id`, `name`, and `price`.
141+
142+
#### Sample Data:
143+
```sql
144+
INSERT INTO products (id, name, price)
145+
VALUES (1, 'Product A', 10.99),
146+
(2, 'Product B', 20.99),
147+
(3, 'Product C', 30.99);
148+
```
149+
150+
#### Orders Table
151+
```sql
152+
CREATE TABLE IF NOT EXISTS orders (
153+
id INT PRIMARY KEY,
154+
product_id INT,
155+
quantity INT
156+
);
157+
```
158+
- **Description:**
159+
Stores order details including order `id`, associated `product_id`, and order `quantity`.
160+
161+
#### Sample Data:
162+
```sql
163+
INSERT INTO orders (id, product_id, quantity)
164+
VALUES (1, 1, 5),
165+
(2, 2, 3),
166+
(3, 3, 1),
167+
(4, 1, 2),
168+
(5, 2, 4);
169+
```
170+
171+
---
172+
173+
## Example Queries
174+
175+
### Query 1: List Employee Projects
176+
Join the **Employees**, **EmployeeProjects**, and **Projects** tables to list each employee's project details.
177+
```sql
178+
SELECT e.Name AS EmployeeName, e.Department, p.Name AS ProjectName, p.Department
179+
FROM Employees e
180+
JOIN EmployeeProjects ep ON e.Id = ep.EmployeeId
181+
JOIN Projects p ON ep.ProjectId = p.Id;
182+
```
183+
184+
### Query 2: List User Sessions
185+
Join the **users** and **sessions** tables to list the session dates for each user.
186+
```sql
187+
SELECT u.name AS user_name, s.session_date
188+
FROM users u
189+
JOIN sessions s ON u.id = s.user_id;
190+
```
191+
192+
### Query 3: Calculate Order Totals
193+
Join the **products** and **orders** tables to calculate the total price for each order.
194+
```sql
195+
SELECT p.name AS product_name, o.quantity, p.price * o.quantity AS total_price
196+
FROM products p
197+
JOIN orders o ON p.id = o.product_id;
198+
```
199+
200+
---
201+
202+
## File Structure
203+
```
204+
Prosnal_Database/
205+
│── README.md
206+
│── schema.sql -- Contains all CREATE TABLE and INSERT statements.
207+
│── queries.sql -- Contains sample SELECT queries.
208+
│── sample_data.csv -- (Optional) CSV files for sample data.
209+
```
210+
211+
---
212+
213+
## Useful Links
214+
- [MySQL Documentation](https://dev.mysql.com/doc/)
215+
- [W3Schools SQL Tutorial](https://www.w3schools.com/sql/)
216+
- [Pandas Documentation](https://pandas.pydata.org/docs/)
217+
218+
---
219+
220+
This `README.md` provides a comprehensive overview of the database creation, data insertion, and query examples. Let me know if you need any modifications or further details!
221+
```
222+
223+
This documentation should help users understand the purpose of each table and query, and it organizes your code in a clear and accessible way.

0 commit comments

Comments
(0)

AltStyle によって変換されたページ (->オリジナル) /