How do I Compare outer variable from a nested loop in php - php

Question

I'm fetching data from two table Tenders and payments I want to display monthly payments with monthly tenders in on array.
But I need to compare if the month and year from the first loop is the same as the month and year from the nested loop
$first_sql = "SELECT YEAR(toll.transaction_date) 'year', MONTHNAME(toll.transaction_date) 'month', COUNT(toll.toll_id) 'count', SUM(toll.tender) 'tender'
FROM toll WHERE company_id = '$COMPANY_ID'
GROUP BY YEAR(toll.transaction_date), MONTHNAME(toll.transaction_date), MONTH(toll.transaction_date)
ORDER BY YEAR(toll.transaction_date) DESC, MONTH(toll.transaction_date) DESC limit 5;";
$scnd_sql = "SELECT YEAR(company_payment_detail.payment_date) 'year', MONTHNAME(company_payment_detail.payment_date) 'month', SUM(company_payment_detail.payment_amount) 'payment'
FROM company_payment_detail
JOIN company_account ON company_payment_detail.company_account_id = company_account.company_account_id
JOIN company ON company.company_id = company_account.company_id
WHERE company_account.company_id = '$COMPANY_ID'
GROUP BY YEAR(company_payment_detail.payment_date), MONTHNAME(company_payment_detail.payment_date),MONTH(company_payment_detail.payment_date)
ORDER BY YEAR(company_payment_detail.payment_date) DESC, MONTH(company_payment_detail.payment_date) DESC limit 5";
The Results
The Loops
$run_first_sql= $conn->query($first_sql);
$run_scnd_sql = $conn->query($scnd_sql);
$chart_data = [];
//first loop
while($row= $run_first_sql->fetch_assoc()){
$arr1 = array(
'y' => $row['year'],
'm' => $row['month'],
'c' => (int)$row['count'],
't' => (float)$row['tender']
);
while($row2= $run_scnd_sql->fetch_assoc()){
if($row['year'] == $row2['year'] && $row['month'] == $row2['month']){
$arr2 = array(
'p' =>(float)$row2['payment'],
);
}else{
$arr2 = array(
'p' =>(float)0,
);
}
}
$arr1 = array_merge($arr1, $arr2);
array_push($chart_data1, $arr1);
}
print_r($chart_data1);

Answer 1

Do a LEFT JOIN of the two queries. If there's no row in the second query for the same month, you'll get NULL in those columns.
SELECT t1.year, t1.month, t1.count, t1.tender, IFNULL(t2.payment, 0) AS payment
FROM (
SELECT YEAR(toll.transaction_date) 'year', MONTHNAME(toll.transaction_date) 'month', COUNT(toll.toll_id) 'count', SUM(toll.tender) 'tender'
FROM toll WHERE company_id = '$COMPANY_ID'
GROUP BY year, month
ORDER BY year DESC, month DESC
limit 5) AS t1
LEFT JOIN (
SELECT YEAR(company_payment_detail.payment_date) 'year', MONTHNAME(company_payment_detail.payment_date) 'month', SUM(company_payment_detail.payment_amount) 'payment'
FROM company_payment_detail
JOIN company_account ON company_payment_detail.company_account_id = company_account.company_account_id
JOIN company ON company.company_id = company_account.company_id
WHERE company_account.company_id = '$COMPANY_ID'
GROUP BY year, month
ORDER BY year DESC, month DESC
limit 5) AS t2
ON t1.year = t2.year AND t1.month = t2.month

Answer 2

You can perform that in a single query, the year and month of both table can be used as their relationship. The query will be looked like this:
$sql = 'SELECT * FROM tenders, payments WHERE tenders.year=payments.year AND tenders.month=payments.month';
while($row = $sql ->fetch_assoc()){
$data = array(
'month' => $row2['month'],
'year' => $row2['year'],
'count' => $row2['count'],
'tender' => $row2['tender'],
);
}
All the tenders year that is equal to payments year AND tenders month that is equal payments month will be fetched.
So if you are going to stick with your way of fetching data, your if condtion code will look like this:
while($row = $run_first_sql->fetch_assoc()){
while($row2 = $scnd_sql ->fetch_assoc()){
if($row['month'] == $row2['month'] && $row['year'] == $row2['year']){
$data = array(
'month' => $row['month'],
'year' => $row['year'],
'count' => $row['count'],
'tender' => $row['tender'],
);
}
}
}
The data of the first query as it iterate will be checked in your second query which takes time.