Detailed analysis of the query package and analysis of the mysql protocol

git

https://github.com/sea-boat/mysql-protocol

Overview

The mysql client can use the query package to send a text-based query to the server.

mysql communication message structure

##string payloadMessage body, the length is the previously specified payload length

Type	Name	Description
int<3>	payload length	Stored according to the least significant byte first, 3-byte payload and 1-byte sequence number combination Into the message header
int<1>	sequence number

query package

Payload

1              [03] COM_QUERYstring[EOF]    the query the server shall execute

More details: https://dev.mysql.com/doc/internals/en/com-query.html

query package Class

/**
 * 
 * <pre class="brush:php;toolbar:false"><b>mysql query packet.</b>

* @author *

seaboat

*

<b>email: </b>849586227@qq.com

*

<b>blog: </b>http://www.php.cn/;/pre>
 * @version 1.0
 * @see http://www.php.cn/
 */public class QueryPacket extends MySQLPacket {
    public byte flag;    
    public byte[] message;    
    public void read(byte[] data) {
        MySQLMessage mm = new MySQLMessage(data);
        packetLength = mm.readUB3();
        packetId = mm.read();
        flag = mm.read();
        message = mm.readBytes();
    }    public void write(ByteBuffer buffer) {        
    int size = calcPacketSize();
        BufferUtil.writeUB3(buffer, size);
        buffer.put(packetId);
        buffer.put(COM_QUERY);
        buffer.put(message);
    }    @Override
    public int calcPacketSize() {        
    int size = 1;        
    if (message != null) {
            size += message.length;
        }        
        return size;
    }    
    @Override
    protected String getPacketInfo() {        
    return "MySQL Query Packet";
    }

}

The above is a detailed analysis of the query package and parsing content of the mysql protocol. For more related content, please pay attention to the PHP Chinese website (www.php.cn)!