Clickhouse Mysql数据导入

=====================方式一=====================

mysql表数据导入：

CREATE TABLE ck_chat 
ENGINE = MergeTree 
ORDER BY id AS 
SELECT * FROM mysql('localhost:3306', 'test', 'chat', 'root', 'yang156');

其中
    ck_chat：为clickhouse数据表
    test：为mysql数据库名
    chat: 为mysql数据表名
    root ： 为mysql用户名
    yang156：为mysql用户密码

FAQ：

1、如果出现Received exception from server (version 20.8.3):
Code: 1000. DB::Exception: Received from localhost:9000. DB::Exception: mysqlxx::ConnectionFailed: 
Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2) ((nullptr):0). 

解决方法：
    a) more /etc/my.cnf |grep sock  #查看sock文件路径: /var/lib/mysql/mysql.sock ,这个是我安装mysql的sock的路径
    b) ln -s /var/lib/mysql/mysql.sock  /tmp/mysql.sock

注意：这种方式是导入的这个时刻的数据存入clickhouse

=====================方式二=====================

mysql库映射至Clickhouse(数据同步)

CREATE DATABASE mysql_db ENGINE = MySQL('localhost:3306', 'test', 'root', 'password')