---------- Forwarded message ---------
From: amihay gonen <
agonenil@gmail.com>
Date: Thu, 15 Jan 2015 13:37
Subject: What is the best way to model attributes relations ?
To: pgsql-general <
pgsql-general@postgresql.org>
I need to support the following queries :
    1. give all documents where attrib X='value'
    2. give me all documents where attib X='value' and attrib Y='value2'
the distinct  attributes if about 10,000,000,000  on about 10 difference type (X,Y etc), so in average 1000 M for each.
each attribute may appear in 10-20 documents .
The model has to optimized to fast read & write.
Here are two model I was thinking of :
Option 1 : Using RDBMS (PG)
One big table (partition by type) , index on value , index on document id ,  type: 
attr type, attr value , document id  .  
For query 1 - it a simple query .
For query 2 - do self join 
Option 2 : 
Same on option 1 but to hold all documents id in one string :
for example :
   'host', 'myhost', apper in ' 3,5,6,7 ,8'
For query 2 : 
do one query - with or , for example : select document ids from ... where (attr='X' and value='Y') 
                                       union 
                                        select document ids from ... where (attr='X' and value='Y')  
and the do set merging 
Other options :
   ? using btree_gin ? 
   elasticsearch ?