MySQL SUM() in step by step column for incomes - php

Question

Database: name_ allmoney
Table name: MONEY
+-----+--------+------------+---------+---------+
| id | name | date | income | account |
+-----+--------+------------+---------+---------+
| 1 | Ann | 01.01.2012 | 100 | 100 |
| 2 | Matt | 02.01.2012 | 100 | 200 |
| 3 | Tom | 03.01.2012 | 100 | 300 |
| 4 | Peter | 04.01.2012 | 100 | 400 |
+-----+--------+------------+---------+---------+
Hello Stackoverflowers! ;)
I'm newbie for MySQL... Last week I've spend searchin for solution for above situation. I'm tryin to create script summing income column, but not only showing the sum of the column like
SELECT *, SUM(kasa) from MONEY GROUP BY id;
but I have to add new column called account, which has the option like my excel sheet:
accout1st row =income1+account1
accout2nd row =income2+account1
accout3rd row =income3+account2
accout4th row =income4+account3
Is there any code or possibility to create column like account in MySQL or PHP?
CREATE TABLE money (
id INT(11) NOT NULL AUTO_INCREMENT,
date DATE DEFAULT NULL,
income DECIMAL(11,4) DEFAULT NULL,
numer_kluczyka INT(11) DEFAULT NULL,
name CHAR(255) CHARACTER SET utf8 COLLATE utf8_polish_ci DEFAULT NULL,
za_co CHAR(255) CHARACTER SET utf8 COLLATE utf8_polish_ci DEFAULT NULL,
account INT(11) DEFAULT NULL,
PRIMARY KEY (id)
) ENGINE=InnoDB AUTO_INCREMENT=10 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci

Answer 1

You can do it using a user variable -
SELECT #m := 0;
SELECT
id,
name,
date,
income,
#m := #m + income AS balance
FROM money
ORDER BY date ASC, id ASC;
The order by should use the primary key for the table.
Splitting the two queries in your PHP should fix the problem -
<?php
$connection = mysql_connect('host', 'user', 'pass') or die('failed to connect');
mysql_select_db("album", $connection) or die('failed to select db');
mysql_query("SELECT #m:=0;");
$result = mysql_query("SELECT id, imie_i_nazwisko, data_wplaty, kasa, #m := #m + income AS balance FROM money ORDER BY data_wplaty ASC , id ASC");
while($row = mysql_fetch_array($result)) {
echo $row['income'] . " " . $row['balance'];
echo "<br />";
}

Answer 2

If I understand your question correctly, you simply need to store the sum computed so far in your php loop.
Something like:
$account = null;
while(($result = /* read mysql result */)) {
if (is_null($account)) { // Handle first row
$account = $result['income'];
}
// Show first columns
echo $result['id'], $result['income'], $account;
$account += $result['income'];
}

Answer 3

Your question seems a bit unclear, but if I've guessed what you want correctly, you could do this with a subselect that sums the income column over all rows up to the current row:
SELECT id, name, date, income,
( SELECT SUM(income) FROM money AS b
WHERE b.id = a.id
AND b.date <= a.date
) AS balance
FROM money AS a
You could also do the same with a join:
SELECT a.id, a.name, a.date, a.income, SUM(b.income) AS balance
FROM money AS a
JOIN money AS b ON (b.id = a.id AND b.date <= a.date)
GROUP BY a.id, a.name, a.date, a.income
(The GROUP BY is supposed to be on the primary key of the money table. It's not entirely clear from your question what the primary key is supposed to be, since it doesn't seem to be id.)
Also note that both of these answers assume that the date columns are unique for each id and sort in ascending order by time, so that the condition b.date <= a.date can find all rows up to and including the current row. If that's not the case, you should either fix your table so that it is, or adjust the query accordingly.
Edit: S0pra's PHP solution will work too. However, the way I read your question, what you want is to sum the past income for each id separately. If so, you can use S0pra's code with a few modifications:
$balance = array();
while ( $result = mysql_fetch_assoc( $res ) ) { // or equivalent
$id = $result['id'];
if ( array_key_exists( $id, $balance ) ) {
$balance[$id] += $result['income'];
} else {
$balance[$id] = $result['income']; // handle first row for this id
}
$result['balance'] = $balance[$id];
// do something with $result here
}