Tutorial: recordid

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Each record in OrientDB has its own self-assigned unique ID within the database, called Record ID or RID that is composed of two parts:

#<cluster-id>:<cluster-position>

• cluster-id is the id of the cluster. Each database can have a maximum of 32,767 clusters (2^15)
• cluster-position is the position of the record inside the cluster. Each cluster can handle up to 9,223,372,035,000,000,000 (2^63) records.

So the maximum size of a database is 2^78 records = 302,231,454,903,657,000,000 records. We never tested such numbers because the lack of hw resources, but we know for sure there are OrientDB users that have databases with Billions of records.

A RID (RecordID) is the physical position of the record inside the database. This means that loading a record by its RID it's blazing fast with response time close to be constant O(1) even if the database grows. This is huge in the BigData age!

To load directly a record via the console use the Load record command. Below we load the record #12:4 of "demo" database.

orientdb> load record #12:4
--------------------------------------------------
ODocument - Class: Company   id: #12:4   v.8
--------------------------------------------------
           addresses : [NOT LOADED: #19:159]
              salary : 0.0                 
           employees : 100004              
                  id : 4                   
                name : Microsoft4          
         initialized : false               
             salary2 : 0.0                 
          checkpoint : true                
             created : Sat Dec 29 23:13:49 CET 2012

The Load record command returns some useful information about this record:

• It's a document. OrientDB supports different types of records, but this tutorials covers documents only
• The class is "Company"
• The current version is 8. OrientDB has a MVCC system, but for now forget about it. Just know that every time you update a record its version is incremented by 1
• we've different field types, "salary" and "salary2" are floats, "employees" and "id" are integers, "name" is a string, "initialized" and "checkpoint" are booleans and "created" is a date-time
• the field "addresses" has been not loaded and it's a LINK to another record #19:159. This is a relationship!

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