How to turn an array into a map in PHP?
This is based on a previous question I asked.
Lets say I have run an SQL query and received the following into a variable $res
:
name | language
-------------------------
bob | English
bob | Dutch
Sally | English
Sally | Spanish
Sally | German
i.e. $res["name"]
currently equals the开发者_如何学JAVA first column etc.
Is there a PHP function or sequence of functions (without writing a loop) to turn $res
into a map so that I could write $res["bob"]
and receive an array ["English", "Dutch"]
or $res["Sally"]
and receive ["English", "Spanish", "German"]
?
$map = array();
foreach ($mysqlResult as $row) {
$map[$row['name']][] = $row['language'];
}
You can do it with mysql using group by :
http://www.tizag.com/mysqlTutorial/mysqlgroupby.php
If there were a native function, it would use a loop internally anyway.
$res = array();
foreach($old as $value) {
$res[$value['name']][] = $value['language'];
}
Edit: I see this is a one to many relationship :)
Another option is to use array_reduce
:
$rows = array_from_sql_query();
$map = array_reduce($rows, function($res, $row) {
$res[$row['name']][] = $row['language'];
return $res;
}, []);
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