What size are the biggest SQL Server database installations in the world?

Look these old numbers:

More recently, check this out: Microsoft Applauds 1.1 Petabytes SQL Server 2008 Database

Since the other answers are outdated / broken references.

Here is an answer from 2014:

Uncompressed, the Options and Equity archive measures 2 petabytes (PB). With page compression, it measures 1.5 PB.

They also claim that on each year they add 500TB to the database.

See: NASDAQ OMX Group Case Study

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