How to get the latest 5 company data from two tables - php

Question

I have 2 tables in mysql database.
a) company
cid company_name
===================
1 AstraZeneca
2 Emirates
3 Development Bank of Singapore
4 Royal Copenhagen
5 xxx
6 xxx
2) history
hid user_id view_id is_save mark_as view date
==============================================================
1 2 2 0 3 2016-08-25 22:06:12
2 3 3 1 3 2016-08-25 22:07:12
3 3 3 0 1 2016-08-25 22:08:12
4 3 2 0 1 2016-08-25 22:09:12
5 2 4 0 1 2016-08-25 22:10:12
6 4 5 0 1 2016-08-25 22:11:12
7 4 6 0 1 2016-08-25 22:12:12
This view_id is containing cid value.
Now, always I want to show latest 5 company_name from company table as ascending order based on history table view_id.
For that purpose I am doing following query. But company_name is not showing either ASC or DESC order
Here is the query :
$getViewID3 = mysqli_query($link, "SELECT view_id, hid, is_save FROM history WHERE user_id = '$user_id' AND mark_as = 3 GROUP BY view_id ORDER BY view_date DESC LIMIT 5 ");
if(mysqli_num_rows($getViewID3) > 0 ) {
while( $fetchViewId3 = mysqli_fetch_array($getViewID3) ) {
$viewid3 = (int) $fetchViewId3['view_id'];
$hid3 = (int) $fetchViewId3['hid'];
$is_save3 = (int) $fetchViewId3['is_save'];
$getCompany = mysqli_query($link, "SELECT company_name FROM company WHERE cid = '$viewid3' ORDER BY company_name DESC");
if(mysqli_num_rows($getCompany) > 0 ) {
while ($fetchCompany2 = mysqli_fetch_array($getCompany)) {
$cName = htmlspecialchars($fetchCompany2['company_name']);
$url_link = "{$url}company.php?cid=$viewid";
if($is_save3 == 1) {
$checked = 'checked = "checked"';
} else {
$checked = '';
}
echo "<li><a onClick='window.document.location=\"$url_link\"'> $cName </a> <input type='checkbox' class='data_save' $checked data-hid='$hid' data-saveid='$viewid3' name='save_history'></li>";
}
}
}
For example : Result is showing : A, E, D, R, L letter order.
It's should be show : A, D, E, L, R letter Order from company_name column.

Answer 1

If I didn't misunderstand:
SELECT
C.company_name
FROM company C
INNER JOIN
(
SELECT
view_id,
MAX(view_date) max_view_date
FROM history
WHERE is_save IN (0,1) AND mark_as = 3
GROUP BY view_id
ORDER BY max_view_date DESC
LIMIT 5
) AS t
ON C.cid = t.view_id
ORDER BY C.company_name ASC;
Note:
Since you want latest 5 companies the following query will put the last view_date beside the view_id.
Now if you sort these rows based on descending order of max_view_date and later limit the result to 5 then you will get at most five view_ids from the inner query.
Later a simple INNER JOIN between this result set and your company table will finish the job.
Sorry, sorting the final result in ascending order of company name will finish the job.
EDIT:
In order to get all the columns from history table and company_name column from company table:
SELECT
C.company_name,
t.*
FROM company C
INNER JOIN
(
SELECT
history.*
FROM history
INNER JOIN
(
SELECT
view_id,
MAX(view_date) max_view_date
FROM history
WHERE is_save IN (0,1) AND mark_as = 3
GROUP BY view_id
ORDER BY max_view_date DESC
LIMIT 5
) AS latestHistory
ON history.view_id = latestHistory.view_id AND history.view_date = latestHistory.max_view_date
) AS t
ON C.cid = t.view_id
ORDER BY C.company_name ASC;