Why and what is use of typecode in Items in Hybris? | explain use of typecode in hybris?

Hello Friends,

Today I want to discuss some useful topic with you about related to typecode in hybris 

Have you ever think of below code

modelService.get(PK) -it will gives result of model of that primary key 

So from above code it seems that in hybris, Primary Key (PK) of all items of whole types is unique 

So again my question is that when above code is execute.  Is hybris search all items in all table in hybris?

Surely answer is NO then how model Service search that items ?

Concept - So here typecode of items comes in picture. Basically in hybris "have you ever think how PK generate in hybris". Primary Key of item of type is generate from using of below things
  a. typeCode of type
  b. getClusterID();
  c. CreationTime();
 
So by above combination of logic , primary key of item created in hybris 

So when you write modelService.get (PK) then from PK it extract typecode of ITEM then it directly apply search in particular table. So I think you got understand about typecode