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HomeDatabaseMysql TutorialSummary of points to note about command packages

githttps://github.com/sea-boat/mysql-protocol Overview After the mysql client connects to the mysql server, when it needs to exit and disconnect, it sends an exit command to the server. The server can directly close the connection or return an OK packet. mysql communication message structure type name description int payload length is stored according to the least significant byte first, 3-byte payload and 1-byte sequence number are combined into a message header int sequence number stringpayload message body , the length is the previously specified payload length. Exit command package Payload1 [01] COM_QUIT More details: http://dev.my

1. mysql protocol exit command package and analysis Code introduction

Summary of points to note about command packages

Introduction: Overview After the mysql client connects to the mysql server, it needs to exit and disconnect When connected, an exit command is sent to the server. The server can directly close the connection or return an OK packet. mysql communication message structure type name description int payload length stored according to the least significant byte first, 3 bytes pa

2. Details of the ping command package of the mysql protocol and Analysis

Summary of points to note about command packages

Introduction: Overview MySQL client can use the ping command to check the status of the server, and it will return normally OK package. mysql communication message structure type name description int payload length stored according to the least significant byte first, 3-byte payload and 1-byte sequence number are combined into a message header in

3. Mysql protocol initialization DB command package and analysis

Summary of points to note about command packages

Introduction: Overview mysql connection If you want to change the default schema of the connection, the client can send an initialization DB command package to the server. mysql communication message structure type name description int payload length stored according to the least significant byte first, 3-byte payload and 1-byte sequence number

4. Delete DB command package and analysis of mysql protocol

Summary of points to note about command packages

##Introduction: Overview MySQL client deletes DB command package Tell the server to delete a schema. mysql communication message structure type name description int payload length stored according to the least significant byte first, 3-byte payload and 1-byte sequence number are combined into a message header int

5. Detailed introduction to the FieldList command package and analysis of the mysql protocol

Summary of points to note about command packages

##Introduction: Overview When the mysql client uses the show column command, it corresponds to this FieldList command package. mysql communication message structure type name description int payload length is stored according to the least significant byte first, the 3-byte payload and the 1-byte sequence number are combined into a message

##6.

Mysql protocol processInfo command package and analysis

Summary of points to note about command packages##Introduction: Overview mysql client passes the processInfo command Query the active processes on the server. mysql communication message structure type name description int payload length stored according to the least significant byte first, 3-byte payload and 1-byte sequence number are combined into a message header int

7. Mysql protocol statistics command package and analysis

Summary of points to note about command packages

Introduction: The MySQL client queries the internal statistics of the server through the statistics command.

8. Access Getting Started Tutorial 18.1 When to use import or join

Introduction: In Access, you can Easily obtain data from external databases, including all current mainstream databases, such as Dbase, Sybase, Oracle, Foxpro, etc. This way you don't have to re-enter the original data one by one. In Access, you can use the Get External Data command to obtain data from an external database. This command package

9. PLSQL statement in oracle

Introduction: 1.set autot off prohibits the use of autotrace command set autot on This command includes exp and stat (execute statements, generate explain plan, generate statistical information) set autot trace does not execute sql statements, but (generates explain plan, generate statistical information) set autot trace exp stat Same as the previous sentence set autot trace st

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