Motivation
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Lots of (semi-)structured data at Google
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URLs:
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Contents, crawl metadata, links, anchors, pagerank,…
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Per-user data:
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User preference settings, recent queries/search results, …
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Geographic locations:
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Physical entities (shops, restaurants, etc.), roads, satellite
image data, user annotations, …
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Scale is large
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Billions of URLs, many versions/page (~20K/version)
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Hundreds of millions of users, thousands of q/sec
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100TB+ of satellite image data
