What is the structure of mysql database?

MySQL data structure is based on the relational model and consists of tables, where rows represent records and columns represent fields. Tables are uniquely identified by primary keys, and foreign keys connect data in different tables. MySQL supports multiple data types, and indexes improve query performance. Foreign keys establish relationships between tables, creating complex data structures.

MySQL database structure

MySQL is a relational database management system (RDBMS) whose data structure is based on relational model. The relational model organizes data into tables or relationships, where each table consists of rows (records) and columns (fields).

Table

• Table is the basic data structure in the MySQL database, used to store specific types of related data.
• Each table has a unique name and contains a fixed number of columns and a variable number of rows.

Rows and columns

• Row (record) Represents a piece of data in the table.
• Column (field) Represents a specific data category in the table.
• Each row contains a value in a specific column.

Primary Keys and Foreign Keys

• The primary key is a column or combination of columns that uniquely identifies each row in a table.
• Foreign keys are columns that connect records in different tables.

Data Types

• MySQL supports a variety of data types, including integers, floating point numbers, characters, and date/time.
• Each data type has specific storage requirements and constraints.

Index

• Index is a structure created on a table to quickly find and retrieve data.
• Indexes can significantly improve query performance, especially for large data sets.

Relationship

• In a relational database, the relationship between tables is established through foreign keys.
• Foreign keys allow joining data in different tables and creating complex data structures.

Example

Consider a database that stores customer information. It might contain a table named customers with the following columns:

• customer_id (primary key)
• name
• address
• email

##This table can be combined with another table that stores order information

orders Association. orders The table may contain the following columns:

• order_id (primary key)
• customer_id (foreign key, join to the customers table)
• product_id
• quantity

via foreign key column

customer_id, we can join the orders in the orders table with the customers in the customers table.

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