 -- Create tables
CREATE TABLE Categories (
 CategoryID INT PRIMARY KEY,
 Name VARCHAR(100) NOT NULL
);

desc Categories; -- Describes Categories table

CREATE TABLE Products (
 ProductID INT PRIMARY KEY,
 Name VARCHAR(100) NOT NULL,
 CategoryID INT,
 Price DECIMAL(10, 2) NOT NULL,
 StockQuantity INT NOT NULL,
 FOREIGN KEY (CategoryID) REFERENCES Categories(CategoryID)
);

desc Products; -- Describes Products table

CREATE TABLE Suppliers (
 SupplierID INT PRIMARY KEY,
 Name VARCHAR(100) NOT NULL,
 ContactNumber VARCHAR(20),
 Email VARCHAR(100)
);

desc Suppliers;

CREATE TABLE Customers (
 CustomerID INT PRIMARY KEY,
 Name VARCHAR(100) NOT NULL,
 Address VARCHAR(255),
 Email VARCHAR(100),
 Phone VARCHAR(20)
);

desc Customers;

CREATE TABLE Orders (
 OrderID INT PRIMARY KEY,
 CustomerID INT,
 OrderDate DATE NOT NULL,
 TotalAmount DECIMAL(10, 2) NOT NULL,
 FOREIGN KEY (CustomerID) REFERENCES Customers(CustomerID)
);

desc Orders;

CREATE TABLE OrderDetails (
 OrderDetailID INT PRIMARY KEY,
 OrderID INT,
 ProductID INT,
 Quantity INT NOT NULL,
 UnitPrice DECIMAL(10, 2) NOT NULL,
 TotalPrice DECIMAL(10, 2) NOT NULL,
 FOREIGN KEY (OrderID) REFERENCES Orders(OrderID),
 FOREIGN KEY (ProductID) REFERENCES Products(ProductID)
);

desc OrderDetails;

CREATE TABLE Transactions (
 TransactionID INT PRIMARY KEY,
 TransactionDate DATE NOT NULL,
 OrderID INT,
 Amount DECIMAL(10, 2) NOT NULL,
 Type ENUM('Sale', 'Refund') NOT NULL,
 FOREIGN KEY (OrderID) REFERENCES Orders(OrderID)
);

desc Transactions;

-- Inserting data

INSERT INTO Categories (CategoryID, Name) VALUES
 (1, 'Fruits'),
 (2, 'Vegetables'),
 (3, 'Dairy'),
 (4, 'Meat'),
 (5, 'Beverages');

SELECT * from Categories; -- showing values in Categories

INSERT INTO Products (ProductID, Name, CategoryID, Price, StockQuantity) VALUES
 (1, 'Apple', 1, 1.99, 100),
 (2, 'Banana', 1, 0.99, 150),
 (3, 'Tomato', 2, 0.79, 200),
 (4, 'Potato', 2, 0.49, 250),
 (5, 'Milk', 3, 2.49, 50),
 (6, 'Cheese', 3, 3.99, 30),
 (7, 'Chicken', 4, 5.99, 20),
 (8, 'Beef', 4, 9.99, 15),
 (9, 'Water', 5, 0.99, 100),
 (10, 'Soda', 5, 1.49, 80);
 
 SELECT * from Products;
 
 INSERT INTO Suppliers (SupplierID, Name, ContactNumber, Email) VALUES
 (1, 'Fresh Farms', '123-456-7890', '[email protected]'),
 (2, 'Green Grocers', '987-654-3210', '[email protected]');
 
 SELECT * from Suppliers;

INSERT INTO Customers (CustomerID, Name, Address, Email, Phone) VALUES
 (1, 'John Doe', '123 Main St, Cityville', '[email protected]', '555-123-4567'),
 (2, 'Jane Smith', '456 Elm St, Townsville', '[email protected]', '555-987-6543');

SELECT * from Customers;

INSERT INTO Orders (OrderID, CustomerID, OrderDate, TotalAmount) VALUES
 (1, 1, '2024-03-21', 25.45),
 (2, 2, '2024-03-20', 15.75);
 
 SELECT * from Orders;

INSERT INTO OrderDetails (OrderDetailID, OrderID, ProductID, Quantity, UnitPrice, TotalPrice) VALUES
 (1, 1, 1, 5, 1.99, 9.95),
 (2, 1, 3, 3, 0.79, 2.37),
 (3, 2, 5, 2, 2.49, 4.98),
 (4, 2, 10, 3, 1.49, 4.47);
 
 SELECT * from OrderDetails;
 
INSERT INTO Transactions (TransactionID, TransactionDate, OrderID, Amount, Type) VALUES
 (1, '2024-03-21', 1, 25.45, 'Sale'),
 (2, '2024-03-20', 2, 15.75, 'Sale');
 
 SELECT * from Transactions;

created 1 year ago by Mariam Bint A. Mannan

MySQL online editor

Write, Run & Share MySQL queries online using OneCompiler's MySQL online editor and compiler for free. It's one of the robust, feature-rich online editor and compiler for MySQL. Getting started with the OneCompiler's MySQL editor is really simple and pretty fast. The editor shows sample boilerplate code when you choose language as 'MySQL' and start writing queries to learn and test online without worrying about tedious process of installation.

About MySQL

MySQL is a open-source, free and very popular relational database management system which is developed, distributed and supported by Oracle corporation.

Key Features:

Open-source relational database management systems.
Reliable, very fast and easy to use database server.
Works on client-server model.
Highly Secure and Scalable
High Performance
High productivity as it uses stored procedures, triggers, views to write a highly productive code.
Supports large databases efficiently.
Supports many operating systems like Linux*,CentOS*, Solaris*,Ubuntu*,Windows*, MacOS*,FreeBSD* and others.

Syntax help

Commands

1. CREATE

CREATE TABLE table_name (
                column1 datatype,
                column2 datatype,
                ....);

Example

CREATE TABLE EMPLOYEE (
  empId INTEGER PRIMARY KEY,
  name TEXT NOT NULL,
  dept TEXT NOT NULL
);

2. ALTER

ALTER TABLE Table_name ADD column_name datatype;

Example

INSERT INTO EMPLOYEE VALUES (0001, 'Dave', 'Sales');

3. TRUNCATE

TRUNCATE table table_name;

4. DROP

DROP TABLE table_name;

5. RENAME

RENAME TABLE table_name1 to new_table_name1;

6. COMMENT

Single-Line Comments:

 --Line1;

Multi-Line comments:

   /* Line1,
   Line2 */

DML Commands

1. INSERT

INSERT INTO table_name (column1, column2, column3, ...) VALUES (value1, value2, value3, ...);

Note: Column names are optional.

Example

INSERT INTO EMPLOYEE VALUES (0001, 'Ava', 'Sales');

2. SELECT

SELECT column1, column2, ...
FROM table_name
[where condition];

Example

SELECT * FROM EMPLOYEE where dept ='sales';

3. UPDATE

UPDATE table_name
SET column1 = value1, column2 = value2, ...
WHERE condition;

Example

UPDATE EMPLOYEE SET dept = 'Sales' WHERE empId='0001';

4. DELETE

DELETE FROM table_name where condition;

Example

DELETE from EMPLOYEE where empId='0001';

Indexes

1. CREATE INDEX

  CREATE INDEX index_name on table_name(column_name);

To Create Unique index:

  CREATE UNIQUE INDEX index_name on table_name(column_name);

2. DROP INDEX

DROP INDEX index_name ON table_name;

Views

1. Create a View

Creating a View:
CREATE VIEW View_name AS 
Query;

2. How to call view

SELECT * FROM View_name;

3. Altering a View

ALTER View View_name AS 
Query;

4. Deleting a View

DROP VIEW View_name;

Triggers

1. Create a Trigger

CREATE TRIGGER trigger_name trigger_time trigger_event
    ON tbl_name FOR EACH ROW [trigger_order] trigger_body
/* where
trigger_time: { BEFORE | AFTER }
trigger_event: { INSERT | UPDATE | DELETE }
trigger_order: { FOLLOWS | PRECEDES } */

2. Drop a Trigger

DROP TRIGGER [IF EXISTS] trigger_name;

Stored Procedures

1. Create a Stored Procedure

CREATE PROCEDURE sp_name(p1 datatype)
BEGIN
/*Stored procedure code*/
END;

2. How to call Stored procedure

CALL sp_name;

3. How to delete stored procedure

DROP PROCEDURE sp_name;

Joins

1. INNER JOIN

SELECT * FROM TABLE1 INNER JOIN TABLE2 where condition;

2. LEFT JOIN

SELECT * FROM TABLE1 LEFT JOIN TABLE2 ON condition;

3. RIGHT JOIN

SELECT * FROM TABLE1 RIGHT JOIN TABLE2 ON condition;

4. CROSS JOIN

SELECT select_list from TABLE1 CROSS JOIN TABLE2;