Top 10 Largest Databases in the World

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10. Library of Congress
By the Numbers
130 million items (books, photographs, maps, etc)
29 million books
10,000 new items added each day
530 miles of shelves
5 million digital documents
20 terabytes of text data

9. Central Intelligence Agency
By the Numbers
100 FOIA items added each month
Comprehensive statistics on more than 250 countries and entities
Unknown number of classified information

8. Amazon
By the Numbers
59 million active customers
More than 42 terabytes of data

7. YouTube
By the Numbers
100 million videos watched per day
65,000 videos added each day
60% of all videos watched online
At least 45 terabytes of videos

6. ChoicePoint
By the Numbers
250 terabytes of personal data
Information on 250 million people

5. Sprint
By the Numbers
2.85 trillion database rows.
365 million call detail records processed per day
At peak, 70,000 call detail record insertions per second

4. Google
By the Numbers
91 million searches per day
accounts for 50% of all internet searches
Virtual profiles of countless number of users

3. AT&T
By the Numbers
323 terabytes of information
1.9 trillion phone call records

2. National Energy Research Scientific Computing Center
By the Numbers
2.8 petabytes of data
Operated by 2,000 computational scientists

1. World Data Centre for Climate
By the Numbers
220 terabytes of web data
6 petabytes of additional data


* Additional Databases
The following databases were unique (and massive) in their own right, and just fell short of the cut on our top 10 list.
Nielsen Media Research / Nielsen Net Ratings

Myspace

United States Customs

HPSS