Consistency (CAP) and Durability (ACID): WriteConcerns
Consistency-level can be picked *per-query*:
workout->steps;
$c->insert( [
'person' => 'derickr',
'steps_made' => [
'20140201' => 10800
],
*[ 'w' => 1 ]*
);]]>
But also with defaults:
$m = new MongoClient("mongodb://localhost/?w=*majority*");