Database Principles Lab Tutorial349

Introduction

A database is a collection of structured data, stored in a computer system, that can be accessed and manipulated by various applications. Database management systems (DBMSs) are software systems that provide the functionality to create, maintain, and query databases. This lab tutorial will provide an introduction to the fundamental principles of databases and DBMSs, and will guide you through the steps of creating and using a database using a popular open-source DBMS, MySQL.

Database Concepts

A database is organized into tables, which are collections of related data. Each table consists of rows and columns. Rows represent individual records, while columns represent attributes of those records. The structure of a table is defined by its schema, which specifies the name, data type, and constraints for each column.

Databases are designed using the relational model, which represents relationships between data using foreign keys. A foreign key is a column in a table that references a primary key in another table. This allows data to be linked together across multiple tables, forming a network of relationships.

Database Management Systems

DBMSs are responsible for managing and accessing data in a database. They provide a variety of features to create, modify, and query databases. Some common DBMSs include MySQL, Oracle, PostgreSQL, and Microsoft SQL Server.

DBMSs typically use a SQL (Structured Query Language) interface for interacting with databases. SQL is a standardized language that allows users to create, modify, and query data using a variety of commands.

Creating a Database

To create a database in MySQL, you can use the following command:```sql
CREATE DATABASE database_name;
```

This will create a new database with the specified name. You can then connect to the database using the following command:```sql
USE database_name;
```

Creating Tables

To create a table in MySQL, you can use the following command:```sql
CREATE TABLE table_name (
column1_name data_type,
column2_name data_type,
...
);
```

The `data_type` can be any of the supported data types in MySQL, such as `INT`, `VARCHAR`, `DATE`, etc.

Inserting Data

To insert data into a table, you can use the following command:```sql
INSERT INTO table_name (column1_name, column2_name, ...)
VALUES (value1, value2, ...);
```

Querying Data

To query data from a table, you can use the following command:```sql
SELECT column1_name, column2_name, ...
FROM table_name
WHERE condition;
```

The `condition` can be any valid SQL expression that evaluates to a Boolean value.

Updating Data

To update data in a table, you can use the following command:```sql
UPDATE table_name
SET column1_name = new_value1, column2_name = new_value2, ...
WHERE condition;
```

Deleting Data

To delete data from a table, you can use the following command:```sql
DELETE FROM table_name
WHERE condition;
```

Conclusion

This lab tutorial has provided an introduction to the fundamental principles of databases and DBMSs. You have learned how to create and use a database using MySQL, including creating tables, inserting data, querying data, updating data, and deleting data. This knowledge will serve as a foundation for further exploration of database technologies and their applications in real-world systems.

2024-11-20

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