Question

我正在尝试使用NodeJS和node-mysql根据时间戳选择一系列记录。我的代码如下：

sql = "SELECT pressure, temp1, temp2, UNIX_TIMESTAMP(timestamp)*1000 
AS unix_timestamp
FROM observations WHERE timestamp >= STR_TO_DATE( ? ,'%Y-%m-%d') 
ORDER BY unix_timestamp DESC LIMIT ?;"

var current_temp = db.query(sql,
start_date, num_records,
  function(err, rows, fields){
     if (err){

变量start_date包含2013-03-01。如果我手动更换“？”在带有'2013-03-01'的STR_TO_DATE表达式中，我的查询有效。但是，如果我尝试使用变量替换，我会收到以下错误：

TypeError: Object 500 has no method 'apply'
at Query.Sequence.end     (/home/ian/Documents/emacs/org/org_files/computer/nodejs/node_modules/mysql/lib/protocol/sequences/Sequence.js:66:24)
at Query.ErrorPacket     (/home/ian/Documents/emacs/org/org_files/computer/nodejs/node_modules/mysql/lib/protocol/sequences/Query.js:89:8)
at Protocol._parsePacket     (/home/ian/Documents/emacs/org/org_files/computer/nodejs/node_modules/mysql/lib/protocol/Protocol.js:169:24)
at Parser.write     (/home/ian/Documents/emacs/org/org_files/computer/nodejs/node_modules/mysql/lib/protocol/Parser.js:62:12)
at Protocol.write     (/home/ian/Documents/emacs/org/org_files/computer/nodejs/node_modules/mysql/lib/protocol/Protocol.js:36:16)
at write (_stream_readable.js:547:24)
at flow (_stream_readable.js:556:7)
at Socket.pipeOnReadable (_stream_readable.js:588:5)
at Socket.EventEmitter.emit (events.js:92:17)
at emitReadable_ (_stream_readable.js:382:10)

Answer 1

您的变量应该在一个数组中，根据它们在SQL语句中出现的顺序定位，如下所示：

    db.query(sql,[start_date, num_records],  function(err, rows, fields){ logic ;})

node-mysql按时间戳选择记录

1 个答案: