我正在使用带有node.js的mysql库来创建此查询:
SELECT vols.id_vol, vols.id_place, vols.id_vol_type, vols.id_user_creator, vols.name, vols.desc, vols.date_creation, vols.date_begin, vols.date_end, vols.duration, ' +
' vols.active, vols.start_time, vols.end_time, vols.insurance, vols.deleted, users.id_user, users.login, users.verified, users.photo_url, comments.message, comments.id_user, place.id_place, place.name AS placeName, place.lat, place.long' +
' FROM vols INNER JOIN users ON vols.id_user_creator = users.id_user INNER JOIN place ON vols.id_place = place.id_place LEFT JOIN comments ON comments.id_vol = vols.id_vol WHERE vols.deleted = 0
返回:
"success": true,
"vols": [
{
"vol": {
"id_vol": 1,
"id_place": 1,
"id_vol_type": 2,
"id_user_creator": 1,
},
"users": {
"id_user": 1,
"login": "",
"verified": 0,
},
"comments": {
"message": "Muito fixe",
"id_user": 3
},
{
"vol": {
"id_vol": 1,
"id_place": 1,
"id_vol_type": 2,
"id_user_creator": 1,
},
"users": {
"id_user": 1,
"login": "",
"verified": 0,
},
"comments": {
"message": "ola",
"id_user": 3
}
目前正在针对该特定卷ID存在的每个评论重复“vol”。可以停止显示重复项并将注释合并到单个阵列上吗?
答案 0 :(得分:0)
这实际上是不可能的,我的意思是你可以用group_concat函数做些什么,但它会很乱。
我在类似情况下通常做的是:
WHERE id IN (1,5,7,8,10)
过滤器)在javascript中会有类似的东西(抱歉不知道node.js,所以我没有精确的解决方案
var results = db.queryResults('SELECT vols.id_vol, vols.id_place, vols.id_vol_type, vols.id_user_creator, vols.name, vols.desc, vols.date_creation, vols.date_begin, vols.date_end, vols.duration, vols.active, vols.start_time, vols.end_time, vols.insurance, vols.deleted FROM vols WHERE vols.deleted = 0');
var lookupByUserID = {};
var lookupByPlaceID = {};
var lookupByVolID = {};
var userIN = [];
var placeIN = [];
var volIN = [];
for (var i = 0; i < results.length; i++)
{
var result = results[i];
if (!lookupByUserID[result.id_user_creator])
lookupByUserID[result.id_user_creator] = [];
lookupByUserID[result.id_user_creator].push(result);
if(!lookupByPlaceID[result.id_place])
lookupByPlaceID[result.id_place] = [];
lookupByPlaceID[result.id_place].push(result);
lookupByVolID[result.id_vol] = result;
userIN.push(result.id_user_creator);
placeIN.push(result.id_place);
volIN.push(result.id_vol);
results.comments = [];
}
var userResults = db.queryResults('SELECT users.id_user, users.login, users.verified, users.photo_url FROM users WHERE id_user IN ('+userIN.join(',')+')');
var placeResults = db.queryResults('SELECT place.id_place, place.name AS placeName, place.lat, place.long FROM place WHERE id_place IN ('+placeIN.join(',')+')');
var commentResults = db.queryResults('SELECT comments.id_vol, comments.message, comments.id_user FROM comments WHERE id_vol IN ('+volIN.join(',')+')');
for (var i = 0; i < userResults.length; i++)
{
var user = userResults[i];
for (var j = 0; j < lookupByUserID[user.id_user].length; j++)
lookupByUserID[user.id_user][j].created_by_user = user;
}
for (var i = 0; i < placeResults.length; i++)
{
var place = placeResults[i];
for (var j = 0; j < lookupByPlaceID[place.id_place].length; j++)
lookupByPlaceID[place.id_place][j].place = place;
}
for (var i = 0; i < commentResults.length; i++)
{
var comment = commentResults[i];
lookupByVolID[comment.id_vol].comments.push(comment);
}
现在对象“结果”应该包含所有信息