Joining two mysql tables and populate an array in php - php

Question

I have two tables
First table name is "Library"
ID Name
1 A
2 B
Second table name is "Books"
BID Book_Creater Book_Name
1 Variation1 Book1
1 Variation2 Book2
1 Variation3 Book3
2 Variation1 Book4
2 Variation2 Book5
The sql is
$sql = mysql_query("select library.ID,books.Book_Creater,books.Book_name from library,books where library.ID = books.BID;
Result is
ID Book_Creater Book_name
1 Variation1 Book1
1 Variation2 Book2
1 Variation3 Book3
2 Variation1 Book4
2 Variation2 Book5
Now I would like to create an array which should look like and this is where I am stuck.
array(
[1] => array(
[Variation1] => Book1
[Variation2] => Book2
[Variation3] => Book3
)
[2] => array(
[Variation1] => Book4
[Variation2] => Book5
)
)
Any suggestion will do great.

Answer 1

$res = array();
//for each result row
while($row = mysql_fetch_array($sql))
{
//add a row to the multi dimensional result array
//where the first key = id and the second key = Book_Creater
$res[$row['id']][$row['Book_Creater']] = $row['Book_name'];
}
print_r($res);

Answer 2

Simple way is to do a join as you currently do, and push them into an array as you loop around (possibly for neatness creating a new sub array explicitly when the ID as a key doesn't already exist).
Something like this:-
<?php
$store_array = array();
$sql = mysql_query("SELECT library.ID,books.Book_Creater,books.Book_name
FROM library
INNER JOIN books
ON library.ID = books.BID");
$result = mysql_query($sql);
while ($row = mysql_fetch_assoc($result))
{
if (!array_key_exists($row['ID'], $store_array))
{
$store_array[$row['ID']] = array();
}
$store_array[$row['ID']][$row['Book_Creater']] = $row['Book_name']
}
print_r($store_array);
?>
You could also shuffle some effort onto the database and bring things back concatenated together. Then just split the results to put into the array:-
<?php
$store_array = array();
$sql = mysql_query("SELECT library.ID, GROUP_CONCAT(CONCAT_WS('#~#', books.Book_Creater,books.Book_name)) AS details
FROM library
INNER JOIN books
ON library.ID = books.BID
GROUP BY library.ID");
$result = mysql_query($sql);
while ($row = mysql_fetch_assoc($result))
{
$store_array[$row['ID']] = array();
$details = explode(',', $row['details']);
foreach($details as $detail)
{
$detail_line = explode('#~#', $row['detail']);
$store_array[$row['ID']][$detail_line[0]] = $detail_line[1];
}
}
print_r($store_array);
?>
Note that if you are doing this with real data you probably want to chose delimiters which are not going to appear in your data, and also that by default GROUP_CONCAT has a fairly limited max length.
Note also I have used mysql_* functions as that is what you seem to be using, but these are deprecated and probably shouldn't be used now.