代码

local mysql = require "resty.mysql"
    local db, err = mysql:new()
    if not db then
        ngx.say("failed to instantiate mysql: ", err)
        return
    end
    db:set_timeout(1000) -- 1 sec

    local ok, err, errno, sqlstate = db:connect{
        host = "xx.xxx.xxx.xx",
        port = 3306,
        database = "xxxx",
        user = "xxxx",
        password = "xxxxxxxxxxxx",
        max_packet_size = 1024 * 1024 }

    if not ok then
        ngx.say("failed to connect: ", err, ": ", errno, " ", sqlstate)
        return
    end
    ngx.say("connected to mysql.")
  
    local select_sql = "select * from xxxx"
    res,err,errno,sqlstate = db:query(select_sql)
        if not res then
        ngx.say("select rows error:",err,",errno:",errno,",sqlstate:",sqlstate)
        return 
    end
    //打印
    LuaPrintTable(res,'table')