使用PHP驱动程序的Mongo独特排序查询

Question

Having some trouble issuing a simple query from the PHP Mongo driver. This is the shell query:

db.testing.distinct('summary.type').sort();

According to the documentation, I can do a db->command to use the distinct query. Here is what I've tried:

$all_types = $db->command(
      array(
             "distinct"      => "summary.type",
             "key"           => "summary.type"
      )
);

var_dump($all_types);

But rather than getting back the data I expect, I only get a cursor with indexes like stats, nscanned and nscannedObjects What am I doing wrong?

Thanks, ns

Answer 1

Commands don't return a MongoCursor object, but always just one document. Just like with findOne(). In this returned document, the values array element in the returned array contains an array of all your results:

<?php
$m = new Mongo; $c = $m->demo->pubs; $c->drop();

$c->insert( array( 'name' => 'Betsy Smith',   'city' => 'London' ) );
$c->insert( array( 'name' => 'London Tavern', 'city' => 'London' ) );
$c->insert( array( 'name' => 'Lammars',       'city' => 'Manchester' ) );
$c->insert( array( 'name' => 'Weatherspoons', 'city' => 'Coventry' ) );

$r = $m->demo->command( array(
    'distinct' => 'pubs',
    'key' => 'city',
    'query' => array( 'name' => array( '$ne' => 'Weatherspoons' ) )
) );
var_dump( $r['values'] );
?>

Which returns:

array(2) {
  [0] =>
  string(6) "London"
  [1] =>
  string(10) "Manchester"
}