MySQL SELECT Statement Explained

In MySQL, the SELECT statement is used to retrieve data from one or more tables. Its basic syntax is:

SELECT 列名1, 列名2, ... FROM 表名;

The column name is the name of the column(s) to be retrieved, which can be one or more columns separated by commas. The table name is the name of the table from which data is being retrieved.

Here are some common uses of SELECT statements:

1. Retrieve data from all columns.

SELECT * FROM 表名;

1. Retrieve data from specific columns:

SELECT 列名1, 列名2, ... FROM 表名;

1. Retrieve data and sort it based on a specific column.

SELECT 列名1, 列名2, ... FROM 表名 ORDER BY 列名;

1. Retrieve data that meets specific criteria.

SELECT 列名1, 列名2, ... FROM 表名 WHERE 条件;

1. Retrieve data and group it based on a specific column.

SELECT 列名1, 列名2, ... FROM 表名 GROUP BY 列名;

1. Retrieve data using aggregate functions such as SUM, COUNT, AVG, etc.

SELECT 聚合函数(列名) FROM 表名;

1. Limit the number of rows retrieved using the LIMIT statement.

SELECT 列名1, 列名2, ... FROM 表名 LIMIT 行数;

These are just some common uses of SELECT statements, in reality more options and syntax can be used as needed.