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What is a Table

In the world of databases, the term 'table' refers to a structured set of data. So, when we talk about tables in MySQL, we are referring to this structured data set, where we can store the data in a database. In MySQL, a table is a combination of rows and columns, where each column denotes a particular field or attribute and each row corresponds to a record.

Structure of a Table​

A MySQL table consists of rows and columns.

  • Columns: These are vertical entities in the table that contain all information associated with a specific field. For instance, in an 'Employees' table, you might have columns such as 'EmployeeID', 'FirstName', 'LastName', 'Email', 'PhoneNumber', etc.

  • Rows: Rows are horizontal entities in a table that contain the records. Each row in the 'Employees' table would hold the specific information about one employee.

Here is a simple representation of a table:

EmployeeIDFirstNameLastNameEmailPhoneNumber
1JohnDoe[email protected]1234567890
2JaneDoe[email protected]0987654321
3JimBeam[email protected]1122334455

In this 'Employees' table, 'EmployeeID', 'FirstName', 'LastName', 'Email', and 'PhoneNumber' are columns, and the details associated with John, Jane, and Jim are rows.

Creating a Table​

To create a table in MySQL, you can use the CREATE TABLE statement. The syntax for creating a table is:

CREATE TABLE table_name (
    column1 datatype,
    column2 datatype,
    column3 datatype,
   ....
);

For example, to create the 'Employees' table, the SQL query would be:

CREATE TABLE Employees (
    EmployeeID int,
    FirstName varchar(255),
    LastName varchar(255),
    Email varchar(255),
    PhoneNumber varchar(20)
);

Here, varchar represents a variable character string, and int represents an integer.

Manipulating Data in a Table​

MySQL provides several commands to manipulate the data in the tables:

  • INSERT INTO: This is used to insert new data into the table.
  • SELECT: Used to select data from the table.
  • UPDATE: This is used to update existing data in a table.
  • DELETE: Used to delete records from a table.

Conclusion​

In MySQL, tables act as a structure to store and organize data effectively. They consist of rows and columns to store records in a structured and easy-to-understand manner. Understanding tables and how to manipulate them is fundamental to working with MySQL, as they form the basis for storing and retrieving data.