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nodejs 连接mysql查询数据,根据什么来判断查询成功?

如题,使用以下语句查询后,要怎么判断查询成功或失败?例如
select * from user where id=1,想要判断数据库是否存在id=1这条数据的话该如何写?

connection.query(sql,sql_params,(err,result)=>{
    
})

if(??){
//数据存在,如何取值做对比?
}else{
//数据不存在,执行其它...
}

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首先判断err,如果err不为空则说明查询发生错误,否则查询成功


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
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