How can I retrieve data from two tables in MySQL?

To retrieve data from two tables, you can use the JOIN statement in MySQL. JOIN statement allows you to combine the data of two or more tables by connecting their columns.

Here are some common types of JOIN statements:

1. Inner Join: Returns rows that have matching values in both tables.

SELECT * FROM 表1 INNER JOIN 表2 ON 表1.列 = 表2.列;

1. LEFT JOIN: Returns all rows from the left table, as well as matching rows from the right table.

SELECT * FROM 表1 LEFT JOIN 表2 ON 表1.列 = 表2.列;

1. RIGHT JOIN: Returns all rows from the right table, along with matching rows from the left table.

SELECT * FROM 表1 RIGHT JOIN 表2 ON 表1.列 = 表2.列;

1. Full join: returns all rows from both the left and right tables, regardless of whether they match.

SELECT * FROM 表1 FULL JOIN 表2 ON 表1.列 = 表2.列;

“Table 1” and “Table 2” are the names of the two tables to be connected, while “column” is the name of the column that will be used to join the two tables.

The symbol “*” in the statement above represents returning data for all columns, but you can also choose specific columns as needed.

It’s important to note that the performance of JOIN statements can be affected by the size of tables and indexes. When using JOIN statements, it’s best to create indexes on the columns being joined to improve query performance.