MySQL

There are many useful instructions for processing values in SQL. Today I will introduce the following instructions:

There are usually several tables in a database, and there are many data stored. In addition to query the data, if we are the database administrator, we also need to know how to “add“, “modify“, “delete” the table and the fields and data in the table.

I briefly mentioned that the WHERE instruction can be used as an IF conditional judgment. Today, I will continue to record how to use WHERE.

Today I record some commonly used instructions of SQL:

• AVG()
• COUNT()
• MAX()
• MIN()
• SUM()

The article records how to use the following SQL instructions of:

• SELECT
• FROM
• WHERE
• GROUP BY
• HAVING
• ORDER BY
• LIMIT