Merging two rows of a table based on same column existence - javascript

Assuming I have a table below:
<pre>
<table>
<tr>
<td><b>id</b></td>
<td><b>name</b></td>
<td><b>rank</b></td>
</tr>
<tr>
<td>A</td>
<td>Chicago</td>
<td>4</td>
</tr>
<tr>
<td>B</td>
<td>New York</td>
<td>3</td>
</tr>
<tr>
<td>A</td>
<td>Chicago</td>
<td>5</td>
</tr>
<tr>
<td>C</td>
<td>Ohio</td>
<td>2</td>
</tr>
<tr>
<td>A</td>
<td>Chicago</td>
<td>3</td>
</tr>
</table>
</pre>
Where the id column relates all the rows.
How can I merge all the rows having the same id value together and the rank column will be the average of all the rows being merged.
E.g the result will look like the table below:
<pre>
<table>
<tr>
<td><b>id</b></td>
<td><b>name</b></td>
<td><b>rank</b></td>
</tr>
<tr>
<td>A</td>
<td>Chicago</td>
<td>4</td>
</tr>
<tr>
<td>B</td>
<td>New York</td>
<td>3</td>
</tr>
<tr>
<td>C</td>
<td>Ohio</td>
<td>2</td>
</tr>
</table>
</pre>
Where 4 in the rank column is the average sum of all the rows merge in the first table
Note:
Each row is an array taken from a 2D array. Therefore the result must be a 2D array.
Using SQL is just too hard as this table comprises of 4 other tables from the database. So I'd prefer the answer in PHP or JavaScript
Thanks


How about
SELECT id, name, avg(rank) FROM table GROUP BY id, name;
The key here is the group by.
As you said your table is created by joining four tables you can use it with a subselect:
SELECT id, name, avg(rank) FROM
(
SELECT * FROM whatver --here goes your statement joining the four tables
)
GROUP BY id, name;


SELECT `id`, `name`, AVG( rank ) AS `rank` FROM table_name GROUP BY `id`, `name`


SELECT ID,NAME,AVG([RANK])[RANK] FROM TABLE GROUP BY ID,NAME

Related

Get a specific row from specific table with JavaScript?

Say my dynamic HTML looks something like this:
<table id="DanishCompanies">
<tr><th>Name</th><th>Employees</th><th>Founded</th></tr>
<tr id="19"><td>Company A</td><td>80</td><td>1980</td></tr>
<tr id="17"><td>Company B</td><td>12</td><td>1910</td></tr>
<tr id="26"><td>Company C</td><td>5000</td><td>2015</td></tr>
</table>
<table id="SwedishCompanies">
<tr><th>Name</th><th>Employees</th><th>Founded</th></tr>
<tr id="10"><td>Company D</td><td>500</td><td>1950</td></tr>
<tr id="12"><td>Company E</td><td>900</td><td>1990</td></tr>
<tr id="17"><td>Company F</td><td>90</td><td>2010</td></tr>
</table>
<table id="NorwegianCompanies">
<tr><th>Name</th><th>Employees</th><th>Founded</th></tr>
<tr id="17"><td>Company G</td><td>105</td><td>1970</td></tr>
<tr id="18"><td>Company H</td><td>100</td><td>1980</td></tr>
<tr id="19"><td>Company I</td><td>45</td><td>2000</td></tr>
</table>
Each tr has an ID, but ID only relatively unique to the table, as other tables might have the ID, and the number of rows might vary.
How would I obtain the founding year (column 2) of a Swedish company with an id of 17?
I would imagine you would do it like this but I fail to find the correct code.
var table = document.getElementById("SwedishCompanies");
var row_index = ??? //should return 2
return table[row_index].cells[2].innerHTML;
I can't use getElementById just to get id "17", because I would risk getting Danish or Norwegian's company because the order of these tables is random.

you're just not using the right selector,
#DanishCompanies tr[id="17"]
will get you the tr with id 17 that's a child of DanishCompanies :
const row = document.querySelector('#DanishCompanies tr[id="17"]');
const year = row.cells[2].innerHTML;
console.log(year);
<table id="DanishCompanies">
<tr>
<th>Name</th>
<th>Employees</th>
<th>Founded</th>
</tr>
<tr id="19">
<td>Company A</td>
<td>80</td>
<td>1980</td>
</tr>
<tr id="17">
<td>Company B</td>
<td>12</td>
<td>1910</td>
</tr>
<tr id="26">
<td>Company C</td>
<td>5000</td>
<td>2015</td>
</tr>
</table>
<table id="SwedishCompanies">
<tr>
<th>Name</th>
<th>Employees</th>
<th>Founded</th>
</tr>
<tr id="10">
<td>Company D</td>
<td>500</td>
<td>1950</td>
</tr>
<tr id="12">
<td>Company E</td>
<td>900</td>
<td>1990</td>
</tr>
<tr id="17">
<td>Company F</td>
<td>90</td>
<td>2010</td>
</tr>
</table>
<table id="NorwegianCompanies">
<tr>
<th>Name</th>
<th>Employees</th>
<th>Founded</th>
</tr>
<tr id="17">
<td>Company G</td>
<td>105</td>
<td>1970</td>
</tr>
<tr id="18">
<td>Company H</td>
<td>100</td>
<td>1980</td>
</tr>
<tr id="19">
<td>Company I</td>
<td>45</td>
<td>2000</td>
</tr>
</table>

this way (id with number values complicates the css select syntax)
function getTDval( tableId, rowId, colNum)
{
return document
.querySelector(`table#${tableId} tr[id="${rowId}"]`)
.cells[colNum].textContent
}
console.log( getTDval('SwedishCompanies','17',2) )
<table id="DanishCompanies">
<tr><th>Name</th><th>Employees</th><th>Founded</th></tr>
<tr id="19"><td>Company A</td><td>80</td><td>1980</td></tr>
<tr id="17"><td>Company B</td><td>12</td><td>1910</td></tr>
<tr id="26"><td>Company C</td><td>5000</td><td>2015</td></tr>
</table>
<table id="SwedishCompanies">
<tr><th>Name</th><th>Employees</th><th>Founded</th></tr>
<tr id="10"><td>Company D</td><td>500</td><td>1950</td></tr>
<tr id="12"><td>Company E</td><td>900</td><td>1990</td></tr>
<tr id="17"><td>Company F</td><td>90</td><td>2010</td></tr>
</table>
<table id="NorwegianCompanies">
<tr><th>Name</th><th>Employees</th><th>Founded</th></tr>
<tr id="17"><td>Company G</td><td>105</td><td>1970</td></tr>
<tr id="18"><td>Company H</td><td>100</td><td>1980</td></tr>
<tr id="19"><td>Company I</td><td>45</td><td>2000</td></tr>
</table>

It is invalid HTML to reuse the same id value within a page. You might use private data-... attributes for that.
Apart from that, the following line gets the human readable text of the third child node (third column in this case), which is the year (as a string).
document.querySelector('#DanishCompanies tr[id="17"]')
.children[2].innerText;

If you can't rely on getElmentById that means that you are doing something wrong, an id should be unique in the whole html. I suggest a new naming technique, you can concatenate the parent table id with the current row id. Example:
<table id="NorwegianCompanies">
<tr><th>Name</th><th>Employees</th><th>Founded</th></tr>
<tr id="NorwegianCompanies17"><td>Company G</td><td>105</td><td>1970</td></tr>
<tr id="NorwegianCompanies18"><td>Company H</td><td>100</td><td>1980</td></tr>
<tr id="NorwegianCompanies19"><td>Company I</td><td>45</td><td>2000</td></tr>
</table>
In that way you can simply call
const row = document.getElementById(rowId)

How to delete specific table rows with javascript?

How can I delete specific table rows by giving up the row number in an input field?
The table I want to target: Complete code is linked below.
<table id="uitvoertabel" border="1">
<tr>
<th></th>
<th>Voornaam</th>
<th>Achternaam</th>
<th>Aantal punten</th>
</tr>
<tr>
<td>1</td>
<td>John</td>
<td>Cruijff</td>
<td>54</td>
</tr>
<tr>
<td>2</td>
<td>Frans</td>
<td>Bauer</td>
<td>47</td>
</tr>
<tr>
<td>3</td>
<td>Selah</td>
<td>Sue</td>
<td>93</td>
</tr>
</table>
This is the complete code: https://jsfiddle.net/c6oLf8ye/1/

Pass the row number you want to delete like 0,1,2,3...
document.getElementById("uitvoertabel").deleteRow(0);
updated the same in: https://jsfiddle.net/3v2rdbmt/

Changing row order in a table - prevent changing the header

the code below allows reordering of table rows (moving a row up or down)
for some reason, the following code in IE11 allows changing the header row as well , although i specified "tbody tr:first" as my filter
what am I doing wrong?
function upAction(){
var row = $("input[name='select_radio']:checked").parents("tbody tr:first");
row.insertBefore(row.prev());
}
function downAction(){
var row = $("input[name='select_radio']:checked").parents("tbody tr:first");
row.insertAfter(row.next());
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.0/jquery.min.js"></script>
<button onclick="upAction()">Up</button>
<button onclick="downAction()">down</button>
<table >
<tr>
<th>Printer</th>
<th>Printer ID</th>
<th>Printer Description</th>
</tr>
<tbody>
<tr>
<td><input type="radio" name="select_radio"/></td>
<td>x300</td>
<td>3</td>
<td>new printer installed in 3th floor</td>
</tr>
<tr>
<td><input type="radio" name="select_radio"/></td>
<td>x400</td>
<td>5</td>
<td>laser printer</td>
</tr>
<tr>
<td><input type="radio" name="select_radio"/></td>
<td>Office jet 3</td>
<td>6</td>
<td>old student printer</td>
</tr>
</tbody>
</table>

Filtering: How to hide/show (toggle) certain table rows on click?

Assuming this table (actually it could have more columns and rows):
<table id="vehicles">
<tr>
<th>Type</th>
<th>Color</th>
<th>Wheels</th>
</tr>
<tr>
<td>Car</td>
<td>Red</td>
<td>4</td>
</tr>
<tr>
<td>Motorcycle</td>
<td>Green</td>
<td>2</td>
</tr>
<tr>
<td>Bike</td>
<td>Blue</td>
<td>2</td>
</tr>
<tr>
<td>Car</td>
<td>Blue</td>
<td>4</td>
</tr>
<tr>
<td>Bike</td>
<td>Green</td>
<td>2</td>
</tr>
<tr>
<td>Motorcycle</td>
<td>Red</td>
<td>2</td>
</tr>
</table>
Now my goal is to be able to click on the table data (cells), for example "Car", and then show only the two cars. Another click on "Car" should show the hole table again. Or one click on "Red", and then only the red vehicles (red car and red motorcycle) should be shown. How can this be achieved using jQuery?

$(function () {
$( "td" ).on( "click", function() {
var type = $(this).text();
$('td:first-child').parent('tr:not(:contains('+type+'))').toggle();
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<table id="vehicles">
<tr>
<th>Type</th>
<th>Color</th>
<th>Wheels</th>
</tr>
<tr>
<td>Car</td>
<td>Red</td>
<td>4</td>
</tr>
<tr>
<td>Motorcycle</td>
<td>Green</td>
<td>2</td>
</tr>
<tr>
<td>Bike</td>
<td>Blue</td>
<td>2</td>
</tr>
<tr>
<td>Car</td>
<td>Blue</td>
<td>4</td>
</tr>
<tr>
<td>Bike</td>
<td>Green</td>
<td>2</td>
</tr>
<tr>
<td>Motorcycle</td>
<td>Red</td>
<td>2</td>
</tr>
</table>
Stores the text from current td, hides tr nodes which do not contain the text.

Here's a really really simple test that might help you get started.
$(function () {
$("#vehicles tr td").click(function () {
var desc = $(this).html();
$("#vehicles tr").css("background-color", "white");
$("#vehicles").find(":contains(" + desc + ")").closest("tr").css("background-color", "red");
});
});
This assigns a click event to every TD element, stores its value somewhere and then checks if said value exists in the table, highlighting the elements that are matched. Give it a spin, I think it'll set you off in the right direction.

How to bifurcate data in table according to a particular value

In the table I am receiving data from the db, and all the marks have a particular value A or B. According to the value I need to separate the data , if the mark has value A it should be stored under the A and if mark has the value B it should be stored under B. I am not sure how to write the jquery for this problem. I have attached a fiddle along with the post. Showing only the html and the required format of the table.
<table style="width:300px">
<tr>
<td>Marks</td>
<td>Value</td>
</tr>
<tr>
<td>30</td>
<td>a</td>
</tr>
<tr>
<td>50</td>
<td>a</td>
</tr>
<tr>
<td>20</td>
<td>a</td>
</tr>
<tr>
<td>50</td>
<td>b</td>
</tr>
<tr>
<td>65</td>
<td>b</td>
</tr>
<tr>
<td>75</td>
<td>b</td>
</tr>
</table>
<br>Required Table format
<table style="width:300px">
<tr>
<th>a</th>
<th>b</th>
</tr>
</table>
http://jsfiddle.net/yzzp5/

Try this,
<table style="width:300px" id="marksId">
<tr>
<td>Marks</td>
<td>Value</td>
</tr>
<tr>
<td>30</td>
<td>a</td>
</tr>
<tr>
<td>50</td>
<td>a</td>
</tr>
<tr>
<td>20</td>
<td>a</td>
</tr>
<tr>
<td>50</td>
<td>b</td>
</tr>
<tr>
<td>65</td>
<td>b</td>
</tr>
<tr>
<td>75</td>
<td>b</td>
</tr>
</table>
<br>
Required Table format
<table style="width:300px" id="reqtable">
<tr>
<td>a</td>
<td>b</td>
</tr>
</table>
Your script goes here
$(function(){
var data={'a':[],'b':[]};
$('#marksId tr').each(function(index,tr){
if($(tr).find('td').eq(1).text()=='a'){
data.a.push($(tr).find('td').eq(0).text());
}
if($(tr).find('td').eq(1).text()=='b'){
data.b.push($(tr).find('td').eq(0).text());
}
});
var HTML='';
// alert(JSON.stringify(data))
// if both have equal counts
$.each(data.a,function(idx,val){
HTML+='<tr><td>'+data.a[idx]+'</td><td>'+data.b[idx]+'</td></tr>';
});
// alert(HTML);
$('#reqtable').append(HTML);
});
You might need to change this code based on requirement but it will give you an idea to work on
Check Example here also.

Categories

Resources