mongodb: update nested document by an array?

Question

I have a deeply nested PHP array which I saved as a document in Mongo and ended up with this structure:

{ 
"_id" : "...", 
"categ1" : { 
 "aaa" : 112.6736, 
 "bbb" : 83.9137, 
 "ccc" : 80.3322,
 .....
 }, 
"categ2" : { 
 "xxx" : 1, 
 "yyy" : 22, 
 "zzz" : 7,
 "subcateg" : {
 "sub1" : 1,
 "sub2" : 22
 }
 } 
}

Now, I have another array with a similar structure and I would like to increase the values of the record, by the values of the modifier array:

$modifier=array(
 'categ1' => array(
 'aaa' => 3,
 'bbb' => -1,
 'mmm' => 11
 ),
 'categ2' => array(
 'yyy' => -2,
 'subcateg' => array(
 'sub1' => -1
 )
 )
 );

How can I increase the values inside the document by the values of the $modifier all at once, in a single query, and without loading the entire document ?

I've looked around the web but couldn't find any info on this. Also, i'm pretty newbie at Mongo. Thanks

• Abhi: What you meant by increase the values of the record? Did you mean replace by modifier
• Mixxed: what i mean is: i need to increase the values of aaa, bbb, xxx by those specified in modifier[aaa,bbb....]

Answer 1

You can get your $modifier array to look like this:

$modifier = array(
 'categ1.aaa' => 3,
 'categ1.bbb' => -1,
 'categ1.mmm' => 11,
 'categ2.yyy' => -2,
 'categ2.subcateg.sub1' => -1
)

Link for how to get that.

Then you should be able to simply use:

$col->update(
 array("_id" => "..."),
 array('$inc' => $modifier),
 array("upsert" => true)
);