Join mysql query results to an array

Question

I am trying to generate a table list from data held in 2 tables. One table is called PrimaryEvents and some sample data looks like:

|id|event   |validity|eventsrequired
|1 |event1  |7       |10
|1 |event2  |25      |1
|1 |event3  |12      |50

id here is just the user id of whoever created the data.

The second table is called portfolio, some sample data looks like:

|id|name    |number|datacompleted
|21|event1  |3     |2014-07-07
|15|event1  |5     |2014-07-05
|21|event2  |5     |2014-05-08
|15|event1  |1     |2013-05-05
|15|event1  |1     |2014-05-05
|21|event1  |13    |2014-08-07
|21|event1  |6     |2014-07-08

id here is the id of the user that has completed the event.

I have a query that populates an array to allow a table to be shown to the user, the table shows a list of ALL the events from PrimaryEvents with a left join of data from portfolio if they have completed an event by the same name.

I would like to change the functionality slightly to allow for the following: Only events that are within the validity period date range are merged, AND the merged data automatically SUMs the number (from portfolio.number).

I am not sure how to progress this really. Currently, I have managed to extract the data range using the following code:

$currentDate = DATE("Y-m-d");

$eventList = query("SELECT event,validity FROM PrimaryEvents ORDER BY event");

foreach ($eventList as $row)
    {
    //
    $event["validity"] = $row["validity"];
    $validityDate = Date("Y-m-d", strtotime("-". $row["validity"] . "days"));
    $eventsDateValidCompleted = query("SELECT * FROM portfolio WHERE id = ? AND datecompleted BETWEEN ? AND ? ORDER BY name", $_SESSION["id"], $validityDate , $currentDate);
    }   

What I am missing is how to do something useful with the daterange sorted array data.

Questions: 1) How can I SUM the event data within the valid date range (IE returned in $eventsDateValidCompleted array)?

2) How can I LEFT JOIN this array of data to each line of my current query?

    $allEvents = query("SELECT * FROM PrimaryEvents LEFT JOIN portfolio ON (PrimaryEvents.event = portfolio.name) WHERE PrimaryEvents.role = ? AND (portfolio.id = ? Or portfolio.id is null) ORDER BY PrimaryEvents.event", $currentRole, $_SESSION["id"]);

3) Is there a better way to make this happen?

Thanks for any help that can be offered on this.

Answer 1

You can sum values from a query in MySQL using the SUM() function along with a GROUP BY clause. For example if you wanted to know the sum of all relevant portfolio.number values for a given user id and date range you could change this line:

$eventsDateValidCompleted = query("SELECT * FROM portfolio WHERE id = ? AND datecompleted BETWEEN ? AND ? ORDER BY name", $_SESSION["id"], $validityDate , $currentDate);

to this:

$eventsDateValidCompleted = query("SELECT SUM(number) AS total_number FROM portfolio WHERE id = ? AND datecompleted BETWEEN ? AND ? GROUP BY id", $_SESSION["id"], $validityDate , $currentDate);

And if you wanted to get this sum value by event, and as part of the original query you could do something like this:

SELECT e.event,e.validity, SUM(p.number) AS total_number
FROM PrimaryEvents e 
LEFT JOIN portfolio p ON p.name = e.event
GROUP BY e.id
ORDER BY e.event

Answer 2

I'm not sure I understand exactly what you want, but I suggest using SQL SUM() and GROUP BY along these lines:

SELECT pe.id, pe.event, sum(p.number) FROM PrimaryEvents pe
LEFT JOIN portfolio p ON (pe.event = p.name) AND p.id = pe.role AND p.datecompleted BETWEEN ? AND ?
WHERE pe.role = ? 
GROUP BY pe.id, pe.event

But, as I said, your (reduced) data model and the queries are not quite consistent, which is why I cannot tell if the above will do anything for you.