I have the following problem:
I want to read out my table names from a SQL database and then make a comparison as to whether it already exists. I know there is the formula IF EXISTS ... but IF doesn't work .. So here's my previous variant:
First i extracted everything before the filename.csv (C:\Users\Frederic\Desktop\Drag&Drop...) and then the ".csv". Do not be surprised why 51;) The filename is so long
var filename = filePath.slice(51);
var richtigername = filename.replace(".csv","").toString();
console.log(richtigername)
here the result in the console:
for example: fxbewertung
As a second step I let me show the file names:
connection.query('Show tables from datein', function(err, datein) {
let string = JSON.stringify(datein);
let json = JSON.parse(string);
console.log(json)
here the result in the console:
[ { Tables_in_datein: 'fxbewertung' },
{ Tables_in_datein: 'kontoauszug' },
{ Tables_in_datein: 'lsreport' } ]
Furthermore, I extracted the values (name of the SQL tables):
for (var k = 0; k < json.length; k++) {
var werte = Object.values(json[k])
console.log(werte)
};
here the result in the console:
[ 'fxbewertung' ]
[ 'kontoauszug' ]
[ 'lsreport' ]
Now I don't know how i can take the comparison that for example for the file fxbewertung exist a database ('fxbewertung').
My consideration is to somehow browse the individual arrays .. or merge and then browse. At the end should come out true or false
P.S .: it may well be complicated yet but I'm not a real programmer or something;)
Best regards
Frederic
You can use some() method to check if a table exists for that filename.
var tableExists = tables.some(item => item['Tables_in_datein'] === filename);
Live Example:
var tables = [{
Tables_in_datein: 'fxbewertung'
},
{
Tables_in_datein: 'kontoauszug'
},
{
Tables_in_datein: 'lsreport'
}
];
var filename = 'fxbewertung';
var tableExists = tables.some(item => item['Tables_in_datein'] === filename);
if (!tableExists) {
// Table not found for filename.
} else {
// Table found. Do something.
}
Assuming you finished executing your query and stored the data as following:
const queryResult = [ { Tables_in_datein: 'fxbewertung' },
{ Tables_in_datein: 'kontoauszug' },
{ Tables_in_datein: 'lsreport' } ]
You'll then need to map this array to extract the values and store them in a single array like so:
const values = queryResult.map(e=>e[Object.keys(e)[0]]) // ["fxbewertung", "kontoauszug", "lsreport"]
Since you're looking for a true/false result by giving a file name, you'll need to use indexOf to achieve that.
const valueExists = filename => values.indexOf(filename) !== -1
After that execute valueExists with the file name you're looking for:
valueExists("kontoauszug"); // true
valueExists("potato"); // false
Hope this helps!
An efficient solution could be to use Array.prototype.find(). Where it would return from the moment it finds a truthy value and would not iterate till the end (unless the match exists at the end).
Demo Code:
const tablesArr = [
{
Tables_in_datein: "fxbewertung"
},
{
Tables_in_datein: "kontoauszug"
},
{
Tables_in_datein: "lsreport"
}
];
const tabletoFind = "fxbewertung";
const tableFound = tablesArr.find(item => item["Tables_in_datein"] === tabletoFind) ? true: false;
console.log(tableFound);
if(tableFound){
//*yes table found*/
}else{
///*nope table not found*/
}
I am new to JS and the concepts of organising data elude me a little, trying to take data from a specific array format (as this is what I have to work with) and output it into another specific JSON format.
This is to pass data to the D3 sankey module
https://github.com/d3/d3-plugins/blob/master/sankey/sankey.js
I can't figure out is how to add the index of the node into the links, rather than the name.
Really I am just totally lost with it!
I made a fiddle here:
https://jsfiddle.net/adamdavi3s/kw3jtzx4/
Below is an example of the data and the output required
var data= [
{"source":"Agricultural 'waste'","target":"Bio-conversion","value":"124.2729"},
{"source":"Bio-conversion","target":"Electricity grid","value":"0.597"},
{"source":"Bio-conversion","target":"Losses","value":"26.862"},
{"source":"Bio-conversion","target":"Liquid","value":"280.322"},
{"source":"Losses","target":"Liquid","value":"280.322"}
];
var output= {
"nodes":[
{"name":"Agricultural 'waste'"},
{"name":"Bio-conversion"},
{"name":"Electricity grid"},
{"name":"Losses"},
{"name":"Liquid"}
],
"links":[
{"source":0,"target":1,"value":124.729},
{"source":1,"target":2,"value":0.597},
{"source":1,"target":3,"value":26.862},
{"source":1,"target":4,"value":280.322},
{"source":3,"target":4,"value":280.322}
]
};
Here is my code from the fiddle thusfar
var data=[{"source":"Agricultural 'waste'","target":"Bio-conversion","value":"124.2729"},
{"source":"Bio-conversion","target":"Electricity grid","value":"0.597"},
{"source":"Bio-conversion","target":"Losses","value":"26.862"},
{"source":"Bio-conversion","target":"Liquid","value":"280.322"},
{"source":"Losses","target":"Liquid","value":"280.322"}
];
var sourceArray=[];
for (var i=0; i <data.length; i++ ) {
var node= {"name":data[i].source};
var found = jQuery.inArray(node, sourceArray);
if (found < 0) {
// Element was not found, add it.
sourceArray.push(node);
}
}
console.log(sourceArray);
In javascript:
[ ] annotations are used to describe an Array, like:
var names=["John","Lisa"]
{ } Its are used to describe an Object
var person = {"name" : "John", "age" : 23}
You can use them inside one another
var people=[{"name" : "John", "age" : 23},{"name" : "Lisa", "age" : 44}]
Try this:
var data=[{"source":"Agricultural 'waste'","target":"Bio-conversion","value":"124.2729"},
{"source":"Bio-conversion","target":"Electricity grid","value":"0.597"},
{"source":"Bio-conversion","target":"Losses","value":"26.862"},
{"source":"Bio-conversion","target":"Liquid","value":"280.322"},
{"source":"Losses","target":"Liquid","value":"280.322"}
];
var sourceArray=[];
var linkArray=[];
for (var i=0; i <data.length; i++ ) {
var node= {"name":data[i].source,};
var link= {
"source":i,
"target":data[i].target,
"value":data[i].value,
};
var found = jQuery.inArray(node, sourceArray);
if (found >= 0) {
// Element was found, remove it.
sourceArray.splice(found, 1);
linkArray.splice(found, 1);
} else {
// Element was not found, add it.
sourceArray.push(node);
linkArray.push(link);
}
}
finalArray={"nodes": sourceArray,"links": linkArray}
console.log(finalArray);
https://jsfiddle.net/9x4rdyy7/
Array.reduce() is perfect for this use case ;)
Take a look.
var data=[{"source":"Agricultural 'waste'","target":"Bio-conversion","value":"124.2729"},
{"source":"Bio-conversion","target":"Electricity grid","value":"0.597"},
{"source":"Bio-conversion","target":"Losses","value":"26.862"},
{"source":"Bio-conversion","target":"Liquid","value":"280.322"},
{"source":"Losses","target":"Liquid","value":"280.322"}
];
var output = data.reduce(function(result, item){
for(key in search = ['source','target']) {
var value = item[search[key]];
if(! result.index.hasOwnProperty(value)){
result.index[value] = Object.keys(result.index).length;
result.nodes.push({name: value});
}
}
result.links.push({
source: result.index[item.source],
target: result.index[item.target],
value: Number(item.value)
});
return result;
}, {nodes: [], links: [], index: {}});
delete output.index;
console.log(output);
I am trying to store an array inside and object like this:
var fieldData = {
checkedItem: {
fieldID : “1234”,
SelectedFields : []
}
checkedItem: {
fieldID : “12345”,
SelectedFields : []
}
}
I then want to also replace all selected fields to this object at a later stage.
I am a newbie to this so not sure how it would be done, I have tried everything I can think of!
The later changes to the object will referenced by fieldID.
I have tried stuff like:
fieldData["fieldID"] = selectedFieldSeq;
fieldData[selectedFieldSeq]["SelectedFields"] = $('#Tree').jqxTree('getCheckedItems');
$('#Tree').jqxTree('getCheckedItems');
returns an array of checked items on my tree.
This should do it:
'fieldID = $('#Tree').jqxTree('getCheckedItems');'
'fieldData.SelectedFields = fieldID'
There is a problem with this line :
fieldData[selectedFieldSeq]["SelectedFields"]
fieldData[selectedFieldSeq] is not defined, so it's return undefined
You need to initialize it before using it :
if (!fieldData[selectedFieldSeq]) {
fieldData[selectedFieldSeq] = {
SelectedFields : []
};
}
After, you can assign some value to SelectedFields.
Or did you want to simply do this : fieldData.SelectedFields = ...; ?
Have some issue with push the values in to the javascript array object. Please any one give me the perfect solution
Class code :
var myfuns = ( function(undefined) {
var myarr ={};
function _add(arrayparam){
if (myarr.current == undefined) {
myarr.current = [];
myarr.current.push(options.current_info);
}else{
}
}
function _getList() {
return $.extend(true, {}, myarr);
}
return {
add : _add,
getList : _getList
}
}());
Here am calling and manage the values and keys
function setmydetails(){
var my_param = {
current_info : {
pg : '#tset',
no : 12,
name : "john",
row : 0,
},
userprofile : [],
class : [],
marks : [],
games : []
};
myfuns.add(my_param);
}
Now i got the array
myfuns.getList() // GOT proper array what i passed in my_param
Question : How to modify the existing values from any one of the Inner array from the myarr Obj
Ex: Once First array created later have to modify some from "myarr.current" = > Change current_info.row to 2222
Similar i have to add some array in to " myarr.class " etc
I would like to say try this one not tested
function _add(arrayparam){
if (myarr.current == undefined) {
myarr.current = [];
myarr.current.push(options.current_info);
}else{
$.extend( myarr.current, arrayparam);
}
}
proper source : https://api.jquery.com/jquery.extend/
How to I fetch some rows of particular pattern ?
var list = {
kk_list_name : "jack",
kk_list_no : "123",
kk_first_name :"Reck",
kk_first_no : "5555"
}
Here I want a map with key starting with kk_list
I tried some thing like this, which obviously didnt work.
console.log(list["kk_list_\w+"])
You can try something like this:
function filterArray( list, regex )
{
var outputArray = {};
for( var key in list )
{
if( key.match( regex ) )
{
outputArray[key] = list[key];
}
}
return outputArray;
}
var list = {
kk_list_name : "jack",
kk_list_no : "123",
kk_first_name :"Reck",
kk_first_no : "5555"
}
console.log( filterArray( list, /kk_list_\w+/ ) );
It uses a function to filter the array and make a new one with the regex-selected keys.
You can reduce the object to one with just the keys matching a specified regex using the following:
Object.prototype.reduce = function(regex) {
var newObj = {}, x;
for(x in this) if(this.hasOwnProperty(x) && (!regex || regex.test(x))) newObj[x] = this[x];
return newObj;
};
And then call it as list.reduce(/_first.*$/) => Object {kk_first_name: "Reck", kk_first_no: "5555"}
You can use the following code:
var list = {
kk_list_name : "jack",
kk_list_no : "123",
kk_first_name :"Reck",
kk_first_no : "5555"
}
var line=JSON.stringify(list);
var ar=line.match(/(kk_list[^" :]*)/g)
ar.forEach(function(val){
console.log(eval("list."+val));
});
OUTPUT
jack
123