R MySQL – Create Table

Introduction

Creating tables in a MySQL database from R allows you to structure your data storage efficiently. This can be useful for initializing databases, setting up new data schemas, or creating temporary tables for analysis. The RMySQL package provides functions to connect to MySQL databases and execute SQL queries, including table creation.

Installing and Loading the RMySQL Package

First, you need to install and load the RMySQL package. You can install it from CRAN using the install.packages() function.

Installing the Package

# Install the RMySQL package
install.packages("RMySQL")

Loading the Package

# Load the RMySQL package
library(RMySQL)

Establishing a Connection

To establish a connection to a MySQL database, you need the following information:

• Hostname or IP address of the MySQL server
• Username
• Password
• Database name

Example: Establishing a Connection

Example:

# Establishing a connection to the MySQL database
conn <- dbConnect(RMySQL::MySQL(),
                  dbname = "your_database_name",
                  host = "your_host_name",
                  port = 3306,  # Default MySQL port
                  user = "your_username",
                  password = "your_password")

# Check if the connection is successful
print(conn)

Creating a Table

You can create a table in a MySQL database using the dbSendQuery() function to execute an SQL CREATE TABLE statement.

Example: Creating a Table

Example:

# SQL query to create a table
create_table_query <- "
CREATE TABLE IF NOT EXISTS employees (
  id INT AUTO_INCREMENT PRIMARY KEY,
  name VARCHAR(100) NOT NULL,
  age INT NOT NULL,
  gender CHAR(1) NOT NULL,
  salary DECIMAL(10, 2) NOT NULL
);
"

# Executing the query to create the table
dbSendQuery(conn, create_table_query)
print("Table 'employees' created successfully")

Inserting Data into the Table

After creating a table, you can insert data into it using the dbSendQuery() function to execute SQL INSERT INTO statements.

Example: Inserting Data

Example:

# SQL query to insert data into the table
insert_data_query <- "
INSERT INTO employees (name, age, gender, salary) VALUES
('Alice', 30, 'F', 50000.00),
('Bob', 25, 'M', 45000.00),
('Charlie', 35, 'M', 55000.00),
('Diana', 28, 'F', 48000.00),
('Eve', 40, 'F', 60000.00);
"

# Executing the query to insert data
dbSendQuery(conn, insert_data_query)
print("Data inserted into 'employees' table successfully")

Example Program Using MySQL Connection to Create a Table

Here is an example program that demonstrates the complete process of connecting to a MySQL database, creating a table, inserting data, and closing the connection.

Example Program

# R Program to Demonstrate Creating a Table in MySQL Database

# Install and load the necessary package
install.packages("RMySQL")
library(RMySQL)

# Establishing a connection to the MySQL database
conn <- dbConnect(RMySQL::MySQL(),
                  dbname = "your_database_name",
                  host = "your_host_name",
                  port = 3306,  # Default MySQL port
                  user = "your_username",
                  password = "your_password")

# Check if the connection is successful
print("Connection established:")
print(conn)

# SQL query to create a table
create_table_query <- "
CREATE TABLE IF NOT EXISTS employees (
  id INT AUTO_INCREMENT PRIMARY KEY,
  name VARCHAR(100) NOT NULL,
  age INT NOT NULL,
  gender CHAR(1) NOT NULL,
  salary DECIMAL(10, 2) NOT NULL
);
"

# Executing the query to create the table
dbSendQuery(conn, create_table_query)
print("Table 'employees' created successfully")

# SQL query to insert data into the table
insert_data_query <- "
INSERT INTO employees (name, age, gender, salary) VALUES
('Alice', 30, 'F', 50000.00),
('Bob', 25, 'M', 45000.00),
('Charlie', 35, 'M', 55000.00),
('Diana', 28, 'F', 48000.00),
('Eve', 40, 'F', 60000.00);
"

# Executing the query to insert data
dbSendQuery(conn, insert_data_query)
print("Data inserted into 'employees' table successfully")

# Closing the connection
dbDisconnect(conn)
print("Connection closed")

Conclusion

In this chapter, you learned how to create a table in a MySQL database from R using the RMySQL package. You also learned how to insert data into the table and close the database connection. By mastering these functions, you can efficiently manage and structure your data storage in MySQL databases within your R programs.