Mysql object information instance usage summary

The information_schema database is the database that comes with the MySQL system, which provides access to database metadata. It feels like information_schema is like an encyclopedia of MySQL instances. It records most of the information we need to solve in the database, such as character sets, permissions, database entity object information, external check constraints, partitions, compressed tables, table information, and index information. , parameters, optimization, locks and things, etc. Through information_schema, we can see the running status of the entire MySQL instance, understand the basic information of the MySQL instance, and even optimize and maintain the database. It can be said to be a real encyclopedia, haha. The following is a general classification of these tables based on some small experiences I have learned, so that it is convenient for everyone to summarize. If there are any shortcomings, please point them out and I will modify them as soon as possible. 1: About the system tables related to character sets and collation rules CHARACTER_SETS: Stores database-related character set information (memory storage engine) COLLATIONS: The collation rules corresponding to the character set COLLATIO

1. In MySQL Detailed introduction to information_schema

##Introduction: The information_schema database is the database that comes with the MySQL system. It provides How to access database metadata. It feels like information_schema is like an encyclopedia of MySQL instances. It records most of the information we need to solve in the database, such as character sets, permissions, database entity object information, external check constraints, partitions, compressed tables, table information, and index information. , parameters, optimization, locks and things, etc. Through information_schema, we can see the running status of the entire MySQL instance, understand the basic information of the MySQL instance, and even optimize and maintain the database, etc. It can be said to be a real encyclopedia

2. Detailed introduction to Java reflection to obtain class and object information

Introduction: Reflection can It solves the problem that it is impossible to predict which class an object or class belongs to during compilation, and the information about the object and class must be known based on the information when the program is running. When two people collaborate on development, you only need to know the other party's class name to carry out preliminary development. Get the class object Class.forName(String clazzName) static method. Call the class attribute of the class. Person.class returns the class object of Person (recommended). Call the getClass() method of an object. The specific use should be selected according to the actual situation. ..

##3.

Python data persistence storage: basic use of pickle module

Introduction: Python's pickle module implements basic data sequence and deserialization. Through the serialization operation of the pickle module, we can save the object information running in the program to a file and store it permanently; through the deserialization operation of the pickle module, we can create the object saved by the last program from the file.

4.

Using PHP's Reflection to obtain object information_PHP tutorial

Introduction: Using PHP's Reflection Get object information. PHP5 adds a new feature: Reflection. This feature allows programmers to reverse-engineer class, interface, function, method and extension. Through PHP code, you can get a certain

5.

How to transfer object information in html pages_html/css_WEB-ITnose

Introduction: How to transmit object information in html pages

6.

Use PHP's reflection to obtain object information

Introduction: Use PHP's Reflection to obtain object information. PHP5 adds a new feature: Reflection. This feature allows programmers to reverse-engineer class, interface, function, method and extension. Through PHP code, you can get a certain

7.

ORACLE Recycle Bin current status query and sorting

Introduction: In principle, the Recycle Bin is a data dictionary table that stores the database object information deleted by the user. Next, if you are interested in all aspects of the ORACLE Recycle Bin, you can Please refer to

8. ORACLE data dictionary usage example

Introduction: ORACLE data dictionary is important One of the components, it comes with the creation of the database and changes with the changes of the database. Embodied as some tables and views under the sys user. Data dictionary names are uppercase English characters. The data dictionary contains user information, user permission information, all data object information, table constraints, statistical analysis database views, etc. We cannot manually modify the information in the data dictionary. Many times, the average ORACLE user does not know how to use it effectively. di

9. Introduction to Oracle’s commonly used data dictionary

Introduction: The data dictionary is where Oracle stores information about database objects. A set of table and view structures whose purpose is to describe data. For example, the creator information and creation time information of a table,

10. MySQL5 new features (data dictionary)

Introduction: Because the use of metadata (metadata is those data about the database) has become more and more common, MySQL5 has also designed a special database in the product accordingly. The fixed name of this database is information_schema, the database appears as a central data dictionary, which contains all object information of the database

[Related Q&A recommendations]:

javascript - Does anyone have a way to forcefully clear the information stored in the session every time the servlet is loaded?

The above is the detailed content of Mysql object information instance usage summary. For more information, please follow other related articles on the PHP Chinese website!