I read this and tried implementing my function so that data doesn't change back, but it isn't working with me.
I have an array of objects, where I send them one by one to another function, to add data.
queries.first(finalObject.sectionProjects[i]);
for each one of the sectionProjects, there is a variable achievements, with an empty array.
Upon sending each sectionProject to the queries.first function, I reassign achievements,
finalObject.sectionProjects[i].achievements = something else
When I return from the queries.first function, I lose the data I added.
Am I doing something wrong?
Here's the function:
module.exports = {
first:function(aProject) {
// Latest achievements
var query =
" SELECT ta.description, ta.remarks, ta.expectedECD " +
" FROM project pr, task ta, milestone mi " +
" WHERE pr.ID = mi.project_ID AND mi.ID = ta.milestone_ID " +
" AND ta.achived = ta.percent AND pr.ID = " + aProject.project_id +
" ORDER BY pr.expectedECD " +
" LIMIT 5;"
;
var stringified = null;
pmdb.getConnection(function(err, connection){
connection.query(query, function(err, rows){
if(err) {
throw err;
}else{
var jsonRows = [];
for( var i in rows) {
stringified = JSON.stringify(rows[i]);
jsonRows.push(JSON.parse(stringified));
}
connection.release();
aProject.achievements = jsonRows;
upcomingTasks(aProject);
}
});
});
}
}
This is pmdb.js:
var mysql = require("mysql");
var con = mysql.createPool({
host: "localhost",
user: "user",
password: "password",
database: "database"
});
module.exports = con;
This is the main function that calls queries.first:
// ...Code...
//Number of section projects
var len = jsonRows.length;
console.log("Number of section projects: " + len);
var internal_counter = 0;
function callbackFun(i){
(finalObject.sectionProjects[i]).achievements = [];
queries.first(finalObject.sectionProjects[i]);
if(++internal_counter === len) {
response.json(finalObject);
}
}
var funcs = [];
for (var i = 0; i < len; i++) {
funcs[i] = callbackFun.bind(this, i);
}
for (var j = 0; j < len; j++) {
funcs[j]();
}
Read That Answer twice. Objects acts as a wrapper for the scalar primitive property. You are passing the Objects in to the "queries.first" function.
See this Object reference issue
Edited for the sample code
pmdb.getConnection(function(err, connection){
connection.query(query, function(err, rows){
if(err) {
throw err;
}else{
var jsonRows = [];
for( var i in rows) {
stringified = JSON.stringify(rows[i]);
jsonRows.push(JSON.parse(stringified));
}
connection.release();
aProject.achievements = jsonRows;
upcomingTasks(aProject)
}
});
});
that is not a problem. change it like this. "upcomingTasks" is not a callback function. it is execute after assign the achievements in aProject
Related
First of all, i'm new in JS. I have a function that possibly can use multiple requests to get the final data. How can i do this in the right way? In this example participants won't pushed to the dialogs array because it's in async call.
function getDialogs(token, callback) {
//getting user id
con.query("SELECT user_id FROM users_tokens WHERE user_token = '" + token + "'", function(error, results) {
if (error) {
throw error;
}
var userId = results[0].user_id;
//getting all conversation
con.query("SELECT cc.id as conversation_id, cc.type FROM chat_conversations cc INNER JOIN chat_participants cp ON cc.id = cp.conversation_id WHERE cp.user_id = " + userId + " GROUP BY cc.id", function (error, results) {
if (error) {
throw error;
}
var dialogs = [];
for (let i = 0; i < results.length; i++) {
var dialog = {id: results[i].conversation_id};
//getting chat participants
con.query("SELECT user_id FROM chat_participants WHERE conversation_id = " + results[i].conversation_id + " AND user_id != " + userId, function (error, results) {
var participants = [];
for (let j = 0; j< results.length; j++) {
participants.push(results[j].user_id);
}
dialogs[participants] = participants;
});
dialogs.push(dialog);
}
callback(dialogs);
});
});
}
Technically you can use a single request like this
SELECT user_id FROM chat_participants WHERE conversation_id IN (
SELECT
cc.id as conversation_id,
cc.type
FROM
chat_conversations cc
INNER JOIN chat_participants cp ON cc.id = cp.conversation_id
WHERE
cp.user_id IN (
SELECT
user_id
FROM
users_tokens
WHERE
user_token = "TOKEN"
)
GROUP BY
cc.id
)
but there are a few problems with this approach as well.
First of all, it seems like you are only using the user_id of your first row, so please use LIMIT 1 in such cases.
Second of all, it seems like user_id won't ever have a duplicate, so make it a primary key.
Third of all, don't concat your token, node mysql supports having placeholders using ? in your query, like this:
con.query("SELECT * FROM ? WHERE user_id = ?", ["table_name", "userid"])
Fourth of all, promisify your requests so you don't have a callback hell, do something like:
function promiseRequest(query, placeholders) {
return new Promise((res, rej) => {
con.query(query, placeholders, (err, data) => {
if (err) rej(err);
res(data);
});
});
}
I have researched a lot but have not found solution for my scenario. I have a simple html/javascript app and I package it using cordova. The html page has a form which posts forms to server. I want to save form to sqlite database when the app is offline or no internet connection available.
I am new to sqlite and I have not found any compatible data type to store form to database. If I use TEXT or BLOB it simply stores "[Object HTMLFormObject]" string.
Please check me js code:
db = window.sqlitePlugin.openDatabase({
name: 'ambdb',
location: 'default'
}, function (db) {
db.transaction(function (tx) {
tx.executeSql('CREATE TABLE IF NOT EXISTS FORMS (form BLOB)');
}, function (err) {
alert('Open database ERROR: ' + JSON.stringify(err));
});
});
function storeForms(formRecieved) {
//alert(formRecieved.toString());
//alert('text(): '+ formRecieved.text());
//var jsonString = JSON.stringify(formRecieved);
//var htmlText = escape(formRecieved.innerHTML);
//var htmlText = formRecieved.innerHTML;
//var simplyString = String(formRecieved);
db.transaction(function (tx) {
tx.executeSql('INSERT INTO FORMS (form) VALUES (?)', [formRecieved]);
}, function (err) {
alert('StoreForms ERROR: ' + JSON.stringify(err));
});
}
function readForms(cb) {
var submittedForms = [];
db.transaction(function (tx) {
tx.executeSql('SELECT form FROM FORMS', [], function (tx, results) {
alert('total items: ' + results.rows.length);
for (var i = 0; i < results.rows.length; i++) {
var row = results.rows.item(i)['form'];
//row = JSON.parse(row);
/*var varstring = row.toString();
alert('tostring: ' + varstring);
var parser=new DOMParser();
var x = parser.parseFromString(varstring, "text/html");
alert('x: '+ x);*/
submittedForms.push(row);
}
cb.call(this, submittedForms);
});
});
}
document.addEventListener("online", function (e) {
alert('I am online');
isConnected = true;
var promise1 = new Promise(function (resolve, reject) {
readForms(function (forms) {
resolve(forms);
});
}).then(function (submittedForms) {
var numberOfRows = submittedForms.length;
alert('submittedForms.length: ' + numberOfRows);
if (numberOfRows > 0) {
for (var i = 0; i < numberOfRows; i++) {
alert('Single row: '+ JSON.stringify(submittedForms[i]));
submittedForms[i].submit();
}
//deleteForms();
return false;
}
})
}, false);
The commented code shows the possible ways I have tried to serialize-parse HTML object back and forth just to store it in database.
Please guide me what column data type should I use and how should I handle it in code. Many thanks!
I ended up converting HTMLFormObject to JSON object. And I am saving it as a string in database. And while reading from database, I am parsing it back to JSON object. From this JSON object I am creating a html form.
function storeForms(formRecieved) {
var elements = formRecieved.elements;
var newForm = {};
for (var i = 0; i < formRecieved.length; i++) {
var elementName = elements[i].name;
newForm[elementName] = elements[i].value;
}
var jsonString = JSON.stringify(newForm);
db.transaction(function (tx) {
tx.executeSql('INSERT INTO FORMS (form) VALUES (?)', [JSON.stringify(newForm)]);
}, function (err) {
alert('StoreForms ERROR: ' + JSON.stringify(err));
});
}
function readForms(cb) {
var submittedForms = [];
db.transaction(function (tx) {
tx.executeSql('SELECT form FROM FORMS', [], function (tx, results) {
var row, formToSubmit, input, jsonRow = {};
for (var i = 0; i < results.rows.length; i++) {
row = results.rows.item(i)['form'];
jsonRow = JSON.parse(row);
formToSubmit = createFormToSubmit(jsonRow);
submittedForms.push(formToSubmit);
}
cb.call(this, submittedForms);
});
});
}
function createFormToSubmit(jsonData) {
var formToSubmit = document.createElement("form");
var keys = Object.keys(jsonData);
var fieldName, input;
for (var i = 0; i < keys.length; i++) {
fieldName = keys[i];
input = document.createElement("input");
input.type = "text";
input.name = keys[i];
input.value = jsonData[fieldName];
formToSubmit.appendChild(input);
}
formToSubmit.setAttribute('method', "post");
formToSubmit.setAttribute('action', "https:url");
formToSubmit.setAttribute('target', "transFrame");
return formToSubmit;
}
I am trying to link two tables in DynamoDB for an Amazon Alexa skill. I am using two tables one is named 'yesno' and the other 'fixtures'. The fixtures table has a list of 22 names in each record and these names are in the 'yesno' table along with the column 'goals'. Here you can see the tables in more detail. Name Table:
Fixtures Table:
As you can see there are names that link the two databases together. I use the team1 column to search the fixtures table and use the name column to search the name table. Here is my code for searching:
function readDynamoItem(params2, callback) {
var AWS = require('aws-sdk');
AWS.config.update({region: AWSregion});
var dynamodb = new AWS.DynamoDB();
const names = new Array();
console.log('reading item from DynamoDB table');
dynamodb.scan(params2, function (err, data){
if (err) console.log(err, err.stack); // an error occurred
else{
console.log(data); // successful response
//tried to put a automatic loop for the long bit of code after this but didnt work so anyone with insight on this too would be helpful
/*for(var i = 1; i <= 11; i++){
var str = "T1S";
var pos = i.toString();
pos = str.concat(pos);
names[i] = jsonToString(data.Items[0].pos);
}
for(var j = 1; j <= 11; j++){
str = "T2S";
pos = j.toString();
pos = str.concat(pos);
names[(j+11)] = jsonToString(data.Items[0].pos);
}
*/
names[1] = jsonToString(data.Items[0].T1S1);
names[2] = jsonToString(data.Items[0].T1S2);
names[3] = jsonToString(data.Items[0].T1S3);
names[4] = jsonToString(data.Items[0].T1S4);
names[5] = jsonToString(data.Items[0].T1S5);
names[6] = jsonToString(data.Items[0].T1S6);
names[7] = jsonToString(data.Items[0].T1S7);
names[8] = jsonToString(data.Items[0].T1S8);
names[9] = jsonToString(data.Items[0].T1S9);
names[10] = jsonToString(data.Items[0].T1S10);
names[11] = jsonToString(data.Items[0].T1S11);
names[12] = jsonToString(data.Items[0].T2S1);
names[13] = jsonToString(data.Items[0].T2S2);
names[14] = jsonToString(data.Items[0].T2S3);
names[15] = jsonToString(data.Items[0].T2S4);
names[16] = jsonToString(data.Items[0].T2S5);
names[17] = jsonToString(data.Items[0].T2S6);
names[18] = jsonToString(data.Items[0].T2S7);
names[19] = jsonToString(data.Items[0].T2S8);
names[20] = jsonToString(data.Items[0].T2S9);
names[21] = jsonToString(data.Items[0].T2S10);
names[22] = jsonToString(data.Items[0].T2S11);
}
});
var goals = new Array();
//for loop to be used later when expanding
//for(var i = 1; i <= 22; i++){
var params = {
TableName: 'yesno',
FilterExpression: 'name = :value',
ExpressionAttributeValues: {':value': {"S": names[2]}}
};
dynamodb.scan(params, function (err, data) {
if (err) console.log(err, err.stack); // an error occurred
else{
console.log(data); // successful response
var temp = jsonToString(data.Items[0].goals);
goals[1] = temp;
}
callback(goals[1]);
});
//}
}
function jsonToString(str){
str = JSON.stringify(str);
str = str.replace('{\"S\":\"', '');
str = str.replace('\"}', '');
return str;
}
I am trying to use the goals array to print each persons goals off but right now it won't even print one persons and instead will print an undefined object of some sort. I'm guessing it just can't search the names table using the names array. The main bit of code I am having a problem with is when searching the yesno table as you can see in this code:
var goals = new Array();
//for loop to be used later when expanding
//for(var i = 1; i <= 22; i++){
var params = {
TableName: 'yesno',
FilterExpression: 'name = :value',
ExpressionAttributeValues: {':value': {"S": names[2]}}
};
dynamodb.scan(params, function (err, data) {
if (err) console.log(err, err.stack); // an error occurred
else{
console.log(data); // successful response
var temp = jsonToString(data.Items[0].goals);
goals[1] = temp;
}
callback(goals[1]);
});
//}
I know for sure there is nothing wrong with the implementation but here it is just in case it is helpful:
const handlers = {
'LaunchRequest': function () {
this.response.speak('welcome to magic answers. ask me a yes or no question.').listen('try again');
this.emit(':responseReady');
},
'MyIntent': function () {
var MyQuestion = this.event.request.intent.slots.MyQuestion.value;
console.log('MyQuestion : ' + MyQuestion);
const params2 = {
TableName: 'Fixtures',
FilterExpression: 'team1 = :value',
ExpressionAttributeValues: {':value': {"S": MyQuestion.toLowerCase()}}
};
//const params3 = {
// TableName: 'Fixtures',
// FilterExpression: 'team2 = :value',
// ExpressionAttributeValues: {':value': {"S": MyQuestion.toLowerCase()}}
//};
readDynamoItem(params2, myResult=>{
var say = MyQuestion;
say = myResult;
say = 'The top scorer for ' + MyQuestion + ' is ' + myResult;
this.response.speak(say).listen('try again');
this.emit(':responseReady');
});
},
'AMAZON.HelpIntent': function () {
this.response.speak('ask me a yes or no question.').listen('try again');
this.emit(':responseReady');
},
'AMAZON.CancelIntent': function () {
this.response.speak('Goodbye!');
this.emit(':responseReady');
},
'AMAZON.StopIntent': function () {
this.response.speak('Goodbye!');
this.emit(':responseReady');
}
}
;
I have a for loop going through a JSON array - with help from this stack question
Whilst looping the script does the following:
- Does the JSON item exist in the tables?
- if yes
- Is the data different?
- if yes
- Update
- if no
- Do nothing
- if no
-insert into database
I found this question which allowed me to query on each for loop so I am able to get the names from the JSON and query them correctly :
for(var i=0; i<content.prices.length; i++) {
var price = content.prices[i].price
var itemName = content.prices[i].market_hash_name;
var q = "SELECT * FROM prices WHERE item = ?";
(function() {
var iNameCopy = itemName;
var priceCopy = price;
connection.query(q, iNameCopy, function (err, results) {
if (err) throw err;
if(results.length === 1) {
logger.info(iNameCopy + " does exist");
}
else if (results.length === 0){
logger.info(iNameCopy + " does not exist");
}
});
}());
}
Moving onto adding the if statement inside results.length === 1
for(var i=0; i<content.prices.length; i++) {
var price = content.prices[i].price
var itemName = content.prices[i].market_hash_name;
var q = "SELECT * FROM prices WHERE item = ?";
(function() {
var iNameCopy = itemName;
var priceCopy = price;
connection.query(q, iNameCopy, function (err, results) {
if (err) throw err;
if(results.length === 1) {
if(parseFloat(results[0].current_price) != parseFloat(priceCopy)) {
logger.info(iNameCopy + " does exist with old price: " + results[0].current_price + " and new price: " + priceCopy);
}
}
else if (results.length === 0){
logger.info(iNameCopy + " does not exist");
}
});
}());
}
Again this is still working.
Now finally replacing those loggers with new sql queries is where the code stumbles. The for loop runs as if I keep the loggers they display however the sql query loggers do not display:
I tried both this way I found from the other stack question and without wrapping it in a function but neither worked. Any suggestions?
for(var i=0; i<content.prices.length; i++) {
var price = content.prices[i].price
var itemName = content.prices[i].market_hash_name;
var q = "SELECT * FROM prices WHERE item = ?";
(function() {
var iNameCopy = itemName;
var priceCopy = price;
connection.query(q, iNameCopy, function (err, results) {
if (err) throw err;
if(results.length === 1) {
if(parseFloat(results[0].current_price) != parseFloat(priceCopy)) {
var sql2="UPDATE `prices` SET `current_price` = ?, `timeStamp` = ? WHERE `item` = ?";
(function() {
var iNameCopy2 = iNameCopy
var priceCopy2 = priceCopy
connection.query(sql2, [priceCopy2, 'Now()', iNameCopy2], function(err,results){
logger.info("UPDATE: " + iNameCopy2 + ' has been updated with price ' + priceCopy2);
});
}());
}
}
else if (results.length === 0){
var sql3="INSERT INTO `prices` (`item`, `current_price`, `timeStamp`) VALUES (?, ?, ?)";
(function() {
var iNameCopy3 = iNameCopy
var priceCopy3 = priceCopy
connection.query(sql3, [iNameCopy3, priceCopy3, 'Now()'], function(err,results){
logger.info("INSERT: " + iNameCopy3 + ' has been added with price ' + priceCopy3);
});
}());
}
});
}());
}
note: I have my database connection on the outside of the for loop:
var connection = mysql.createConnection(db_access);
connection.connect(function(err){
if(err){
logger.error('Error connecting to Db');
return;
}
});
So this will be a lot of code, but what matter is on line 22-25, and line 87-91. The rest of the code works. I have a nested function and want to return the JSON string. Using console.log I can tell it is running properly but will not return the JSON string. Look for the part that says //---------this part-------. There are two parts that I am asking about.
exports.post = function(request, response) {
var mssql = request.service.mssql;
//var data = '{"userID":"ryan3030#vt.edu1"}';
var inputJSON = request.body.JSONtext;
var json = JSON.parse(inputJSON);
var userID = json.userID;
mssql.query("EXEC getMeetingInfo ?", [userID],
{
success: function(results3) {
var meetingsToday = results3.length;
var meetingID = results3[0].meetingID;
var meetingName = results3[0].meetingName;
var meetingDescription = results3[0].meetingDescription;
var meetingLength = results3[0].meetingLength;
var meetingNotes = results3[0].meetingNotes;
var hostUserID = results3[0].hostUserID;
//--------------------------------------THIS PART------------------------------
var JSONfinal = allInfoFunction(mssql, meetingID, userID, meetingName, meetingDescription, meetingLength, meetingNotes, hostUserID, meetingsToday);
console.log(JSONfinal);//DOES NOT WORk
response.send(statusCodes.OK, JSONfinal);//DOES NOT WORK
//---------------------------------BETWEEN THESE----------------------------------
},
error: function(err) {
console.log("error is: " + err);
response.send(statusCodes.OK, { message : err });
}
});
};
function allInfoFunction(mssql, meetingID, userID, meetingName, meetingDescription, meetingLength, meetingNotes, hostUserID, meetingsToday){
mssql.query("EXEC getLocation ?", [meetingID],
{ success: function(results2) {
var meetingLocation = results2[0].meetingLocation;
var JSONlocation = {"meetingLocation": meetingLocation};
mssql.query("EXEC getDateTime ?", [meetingID],
{ success: function(results1) {
var length = results1.length;
var dateTime = [];
dateTime[0] = results1[0].meetingDateTime;
for (var x= 1; x < length; x++) {
dateTime[x] = results1[x].meetingDateTime;
}
//console.log(dateTime);
mssql.query("EXEC getDateTimeVote",
{ success: function(results) {
//console.log(results);
var JSONoutput2 = {};
var JSONtemp = [];
var length2 = results.length;
for(var j = 0; j < length; j++){
var vote = false;
var counter = 0;
for(var z = 0; z < length2; z++){
var a = new Date(results[z].meetingDateTime);
var b = new Date(results1[j].meetingDateTime);
if(a.getTime() === b.getTime()){
counter = counter + 1;
}
if((a.getTime() === b.getTime()) && (results[z].userID == userID)){
vote = true;
}
}
var meetingTimeInput = {"time": b, "numVotes": counter, "vote": vote}
JSONtemp.push(meetingTimeInput);
JSONoutput2.meetingTime = JSONtemp;
}
var JSONfinal = {};
var mainInfoArray = [];
var JSONmainInfo = {meetingID: meetingID, meetingName: meetingName, meetingDescription: meetingDescription, meetingLength: meetingLength, meetingNotes: meetingNotes, hostUserID: hostUserID, meetingLocation: meetingLocation };
JSONmainInfo.meetingTime = JSONtemp;
JSONfinal.numMeetingsToday = meetingsToday;
mainInfoArray.push(JSONmainInfo);
JSONfinal.meetingList = mainInfoArray;
//response.send(statusCodes.OK, JSONfinal);
//---------------------------------------AND THIS PART-------------------------------
console.log(JSON.stringify(JSONfinal));//This outputs the correct thing
var lastOne = JSON.stringify(JSONfinal);
return lastOne; //ths dosent work
//-------------------------------------BETWEEN THESE-----------------------------------
},
error: function(err) {
console.log("error is: " + err);
//response.send(statusCodes.OK, { message : err });
}
});
},
error: function(err) {
console.log("error is: " + err);
//response.send(statusCodes.OK, { message : err });
}
});
},
error: function(err) {
console.log("error is: " + err);
//response.send(statusCodes.OK, { message : err });
}
});
}
I've done a little refactoring to your code to take a more modular approach. It becomes quite tricky to debug something like what you have above. Here it is:
exports.post = function(request, response) {
var mssql = request.service.mssql;
var inputJSON = request.body.JSONtext;
var json = JSON.parse(inputJSON);
var userID = json.userID;
var JSONFinal = {};
getMeetingInfo(userID);
function getMeetingInfo(userID){
mssql.query("EXEC getMeetingInfo ?", [userID], {
success: function(results){
JSONFinal.meetingsToday = results.length;
JSONFinal.meetingID = results[0].meetingID;
JSONFinal.meetingName = results[0].meetingName;
JSONFinal.meetingDescription = results[0].meetingDescription;
JSONFinal.meetingLength = results[0].meetingLength;
JSONFinal.meetingNotes = results[0].meetingNotes;
JSONFinal.hostUserID = results[0].hostUserID;
// Call next function
getLocation(JSONFinal);
},
error: function(err) {
console.log("error is: " + err);
response.send(statusCodes.OK, { message : err });
}
});
}
function getLocation(){
mssql.query("EXEC getLocation ?", [JSONFinal.meetingID], {
success: function(results) {
JSONFinal.meetingLocation = results[0].meetingLocation;
// Call next function
getDateTime(JSONFinal);
},
error: function(err) {
console.log("error is: " + err);
}
});
}
function getDateTime(){
mssql.query("EXEC getDateTime ?", [JSONFinal.meetingID], {
success: function(results) {
var length = results.length;
var dateTime = [];
for (var x= 0; x < length; x++) {
dateTime[x] = results[x].meetingDateTime;
}
// Call next function
getDateTimeVote(dateTime);
},
error: function(err){
console.log("error is: " + err);
}
});
}
function getDateTimeVote(dateTime){
mssql.query("EXEC getDateTimeVote", {
success: function(results) {
var JSONtemp = [];
var length2 = results.length;
for(var j = 0; j < dateTime.length; j++){
var vote = false;
var counter = 0;
for(var z = 0; z < length2; z++){
var a = new Date(results[z].meetingDateTime);
var b = new Date(results1[j].meetingDateTime);
if(a.getTime() === b.getTime()){
counter = counter + 1;
}
if((a.getTime() === b.getTime()) && (results[z].userID == userID)){
vote = true;
}
}
var meetingTimeInput = {"time": b, "numVotes": counter, "vote": vote}
JSONtemp.push(meetingTimeInput);
}
var JSONmainInfo = {
meetingID: JSONFinal.meetingID,
meetingName: JSONFinal.meetingName,
meetingDescription: JSONFinal.meetingDescription,
meetingLength: JSONFinal.meetingLength,
meetingNotes: JSONFinal.meetingNotes,
hostUserID: JSONFinal.hostUserID,
meetingLocation: JSONFinal.meetingLocation
meetingTime: JSONtemp
};
var JSONfinal = {
numMeetingsToday: JSONFinal.meetingsToday,
meetingsList: [JSONmainInfo]
};
// Call next function
sendResponse(JSON.stringify(JSONfinal));
},
error: function(err) {
console.log("error is: " + err);
}
});
}
function sendResponse(data){
response.send(statusCodes.OK, data);
}
};
It looks a lot different but the functionality is pretty much the same. The key point if you look at the code is that each subsequent function is executed only after the success of the previous function. This effectively chains the methods together so that they are always executed in order and is the key point of difference.
One thing to note here is the similarity between your
allInfoFunction(...
and my
getMeetingInfo(userID)
Both of these will return undefined more or less immediately, after the MSSQL query is sent to the server. This is because the request is fired asynchronously, and the javascript continues to run through the code. After it's fired of the asynchronous request, it has nothing left to do in that function, so it returns. There is no return value specified so it returns nothing (or undefined if you will).
So all in all, the code in the question code will return undefined and then attempt to send a response before anything has actually happened. This code fixes that problem by firing the sendResponse after all the queries have been executed.
I refactored this code in a text editor and haven't run it, or checked it for errors, so follow the basic outline all you like but it may not be a good idea to copy and paste it without checking it's not broken