javascript - 如何在 node.js 和 mysql 中使用多个 SQL
问题描述
我尝试使用 node.js 和 mysql 放置多个选择查询。但是控制台打印出一些日志说sql有问题..
我还做了多个声明:true;
var mysql = require('mysql');
var pool = mysql.createPool({
connectionLimit : 5,
host : '*.*.*.*',
user : 'root',
password : '****',
database : 'db',
multipleStatements: true
});
我制作了这段代码来计算带有网络地址和子网掩码的主机地址。我想选择与我计算的主机 IP 地址匹配的行。
我创建了 sql 数组并将 SQL 放入数组中......然后我将其转换为字符串形式并解析为一个 sql 语句(我的意思是 sql:“sql1; sql2; sql3;....”)
pool.getConnection(function(err, connection){
var sql ="";
var new_sql = new Array();
if(req.body.search_network){
var search_data = [req.body.search_network, req.body.search_subnet];
console.log("*****:"+search_data);
//calculating host addresses
var NETWORK = req.body.search_network;
var SUBNET = req.body.search_subnet;
var host_cnt = Math.pow(2,(32-SUBNET));
var split_net = NETWORK.split('.');
var NET_1 = Number(split_net[0]);
var NET_2 = Number(split_net[1]);
var NET_3 = Number(split_net[2]);
var NET_4 = Number(split_net[3]);
//network address
console.log(NET_1+"."+NET_2+"."+NET_3+"."+NET_4);
console.log(Math.floor(1/Math.pow(256,3)));
for (var i=1; i<host_cnt-1; i++){
var new_NET_1 = NET_1 + Math.floor(i/Math.pow(256,3));
var new_NET_2 = NET_2 + Math.floor(i/Math.pow(256,2));
var new_NET_3 = NET_3 + Math.floor(i/256);
var new_NET_4 = NET_4 + Math.floor(i%256);
//host address
var IP_HOST = String(new_NET_1)+"."+String(new_NET_2)+"."+String(new_NET_3)+"."+String(new_NET_4);
new_sql.push(" SELECT ARP_TBL.DEVICE_IP as device_ip, IP_MGMT_TBL.IP as ip, IP_MGMT_TBL.IP_TYPE as ip_type, IP_MGMT_TBL.PURPOSE as purpose, IP_MGMT_TBL.OWNER_NAME as name, IP_MGMT_TBL.OWNER_DIV as owner_div, IP_MGMT_TBL.REQUEST_TIME as request_time, ARP_TBL.PORT as port " + "FROM IP_MGMT_TBL left join ARP_TBL on IP_MGMT_TBL.IP = ARP_TBL.ip " +"WHERE ARP_TBL.ip="+IP_HOST);
}
sql = new_sql.join(';')+";";
console.log(sql);
// put query to DB and get results within 'rows'
connection.query(sql, function(err, rows){
if(err) console.error("err:" +err);
console.log("rows:"+ JSON.stringify(rows));
res.render('ipmgmt/detail', {rows: rows});
connection.release();
});
<!-- begin snippet: js hide: false console: true babel: false -->
; SELECT ARP_TBL.DEVICE_IP as device_ip, IP_MGMT_TBL.IP as ip, IP_MGMT_TBL.IP_TYPE as ip_type, IP_MGMT_TBL.PURPOSE as purpose, IP_MGMT_TBL.OWNER_NAME as name, IP_MGMT_TBL.OWNER_DIV as owner_div, IP_MG
MT_TBL.REQUEST_TIME as request_time, ARP_TBL.PORT as port FROM IP_MGMT_TBL left join ARP_TBL on IP_MGMT_TBL.IP = ARP_TBL.ip WHERE ARP_TBL.ip=101.1.47.254;
err:Error: ER_PARSE_ERROR: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '.47.1; SELECT ARP_TBL.DEVICE_IP as dev
ice_ip, IP_MGMT_TBL.IP as ip, IP_MGMT_TBL.' at line 1
rows:undefined
这就是控制台日志所说的。它也是完整日志的一部分。我认为 SQL 查询似乎很好,但它不适用于查询..
解决方案
需要引用IP地址是语法错误的基本解决方案。使用表单的查询来消除对多个查询的需要:
... WHERE ARP_TBL.ip IN ('ip address1', 'ip address 2', ...)
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