= MongoDB =

== Query by data type ==

Select all documents in the inventory collection where the price field value is a Double.

{{{#!highlight javascript
db.inventory.find( { price: { $type : 1 } } )
}}}

Select all documents in the inventory collection where the datex field value is a Date.

{{{#!highlight javascript
db.inventory.find( { datex: { $type : 9 } } )
}}}


== Data types ==

||Type||Number||
||Double||1||
||String||2||
||Object||3||
||Array||4||
||Binary data||5||
||Undefined (deprecated)||6||
||Object id||7||
||Boolean||8||
||Date||9||
||Null||10||
||Regular Expression||11||
||JavaScript||13||
||Symbol||14||
||JavaScript (with scope)||15||
||32-bit integer||16||
||Timestamp||17||
||64-bit integer||18||
||Min key||255||
||Max key ||127||

== PHP driver ==
=== Manual install ===
 * cd /tmp
 * wget http://pecl.php.net/get/mongo-1.4.3.tgz
 * tar xvzf mongo-1.4.3.tgz
 * yum install php-devel #on CentOS
 * phpize
 * ./configure
 * make
 * make install
 * add '''extension=mongo.so''' to /etc/php.ini
 * In CentOS 64 bit the '''mongo.so''' should be located in /usr/lib64/php/modules/mongo.so

== Aggregation examples ==

http://docs.mongodb.org/manual/reference/sql-aggregation-comparison/

=== Example 1 ===

{{{#!highlight sql
SELECT country,city,min(timestampx) as minx,max(timestampx) as maxx,count(*) as countx
FROM collx 
GROUP BY country,city 
WHERE idxyz=1234 AND timestampx>='2011-06-04T00:00:00' AND timestampx<='2012-12-04T23:59:59'
ORDER BY minx
}}}

{{{#!highlight javascript
db.collx.runCommand( 
  {  "aggregate":"collx" , "pipeline":[
      {"$match": 
         {
           idxyz:1234 , 
           "timestampx":{ 
             "$gte":ISODate("2011-06-04T00:00:00") , 
             "$lte":ISODate("2012-12-04T23:59:59") 
           }   
         } 
      } 
      ,
      {"$group": 
         {
           "_id":  {"country":"$country","city":"$city"} , 
           "minx":{"$min":"$timestampx"} , 
           "maxx":{"$max":"$timestampx"} ,  
           "countx":{"$sum":1}  
         }    
      }
      ,
      {
        "$sort":
        { 
          "minx":1
        } 
      } 
    ]       
  }   
)
}}}


{{{#!highlight javascript
db.collx.aggregate( 
     [
      {"$match": 
         {
           idxyz:1234 , 
           "timestampx":{ 
             "$gte":ISODate("2011-06-04T00:00:00") , 
             "$lte":ISODate("2012-12-04T23:59:59") 
           }   
         } 
      } 
      ,
      {"$group": 
         {
           "_id":  {"country":"$country","city":"$city"} , 
           "minx":{"$min":"$timestampx"} , 
           "maxx":{"$max":"$timestampx"} ,  
           "countx":{"$sum":1}  
         }    
      }
      ,
      {
        "$sort":
        { 
          "minx":1
        } 
      } 
    ]       
)
}}}

{{{#!highlight javascript
db.collx.runCommand(  { "aggregate":"collx" , "pipeline":[
      {"$group": { "_id":  {"fld":"$fldx"} , "countx":{"$sum":1}  }   }
      ,
      { "$sort": { "countx":1  } } 
] } ).result
}}}

== Get creation timestamp from document ==
Inside the creation timestamp is stored in the _id field .

Using the method getTimestamp on an ObjectiId, is possible to get the creation timestamp.

{{{#!highlight javascript
// runned inside mongo shell
ObjectId("52840c4facb4f200d8a6518a").getTimestamp()
// returned ISODate("2013-11-13T23:33:35Z")
}}}
== Update field on document ==
{{{#!highlight javascript
db.products.update( 
{ sku: "abc123" },
{ $set: { quantity: 500,  instock: true  }    }
)
}}}

== Find documents that don't have a field ==
{{{#!highlight javascript
db.products.find( { fieldx:{$exists:false} } )
}}}


== Find docs with status equal Failure and only show the _id and status fields ==
{{{#!highlight javascript
db.products.find( {status:"Failure"} , { status:1  } )
}}}

== Set journal small ==
{{{#!highlight bash
# smallfiles=true to the config file /etc/mongodb.conf.
service mongodb stop
cd /var/lib/mongodb/journal
rm *
service mongodb start
mongo 
}}}

== Sort by field ==
 * descending
   * db.rxtx.find().sort({timestamp:0}).limit(10)
 * ascending
   * db.rxtx.find().sort({timestamp:1}).limit(10)