MySQL英文单词汇总「PHP新手收藏」

MySQL英文单词汇总「PHP新手收藏」

MySQL is one of the most popular relational database management systems and is widely used in web development, including PHP. As a PHP beginner, learning MySQL and understanding its terminology is essential for building dynamic and data-driven websites.

1. Database

The first term to know in MySQL is the database. A database is a structured collection of data that is organized and stored for easy retrieval. It acts as a container for tables, views, stored procedures, and other database objects.

When working with databases in MySQL, you need to:

CREATE DATABASE database_name;

2. Table

A table is a collection of related data organized in rows and columns. It represents a specific entity or object within a database.

To create a table in MySQL, you need to specify the table structure:

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

3. Column

A column, also known as a field, is a vertical structure within a table that holds a specific type of data. Each column has a name, data type, and optional constraints.

To add a column to an existing table, you can use the ALTER TABLE statement:

ALTER TABLE table_name 
ADD column_name datatype;

4. Primary Key

A primary key is a column or a combination of columns that uniquely identifies each row in a table. It ensures the integrity and uniqueness of the data.

To define a primary key in MySQL:

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

5. Foreign Key

A foreign key establishes a relationship between two tables. It points to the primary key of another table and ensures referential integrity.

To create a foreign key constraint in MySQL:

CREATE TABLE table_name1 (
    column1 datatype,
    column2 datatype,
    ...
    FOREIGN KEY (column_name) REFERENCES table_name2(column_name)
);

6. Query

A query is a request for data or information from a database. It is composed of SQL statements that specify the data to retrieve.

A simple SELECT statement in MySQL:

SELECT column1, column2
FROM table_name
WHERE condition;

7. Index

An index is a data structure that improves the speed of data retrieval operations on a table. It provides a quick lookup and helps optimize query performance.

To create an index in MySQL:

CREATE INDEX index_name
ON table_name (column_name);

8. Join

A join combines rows from two or more tables based on a related column between them. It allows you to retrieve data from multiple tables in a single query.

An example of an INNER JOIN:

SELECT column1, column2
FROM table1
INNER JOIN table2 ON table1.column_name = table2.column_name;

9. CRUD Operations

CRUD stands for Create, Read, Update, and Delete—the basic operations performed on data in a database.

Examples of CRUD operations in MySQL:

INSERT INTO table_name (column1, column2) VALUES (value1, value2);
SELECT * FROM table_name;
UPDATE table_name SET column1 = value WHERE condition;
DELETE FROM table_name WHERE condition;

Conclusion

By familiarizing yourself with these MySQL terms, you'll have a solid foundation for understanding and working with databases in PHP. Remember, practice is key to mastering these concepts. Start by creating simple tables and performing CRUD operations, and gradually explore more advanced features of MySQL.

Happy coding!