Ask HN: Databases have indexes. Then why have partitions?

#1

Post by matc » Wed, Feb 01, 2012, 3:50 AM UTC

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Re: Ask HN: Databases have indexes. Then why have partitions?

#2

Post by apu » Wed, Feb 01, 2012, 4:23 AM UTC

Uh, what?

Re: Ask HN: Databases have indexes. Then why have partitions?

#3

Post by maxdemarzi » Wed, Feb 01, 2012, 5:12 AM UTC

Because you are keeping 13 months of phone call data and want to easily drop the oldest month every 1st.

Because your queries need to be fast, and you can chop up your data into 1000 pieces (by some column or combination) without adding complexity.

Re: Ask HN: Databases have indexes. Then why have partitions?

#4

Post by AznHisoka » Wed, Feb 01, 2012, 2:56 PM UTC

apu wrote: post #2

Uh, what?

I think this is a legitimate question. I always wondered the same thing.

Re: Ask HN: Databases have indexes. Then why have partitions?

#5

Post by matc » Thu, Feb 02, 2012, 4:30 AM UTC

maxdemarzi wrote: post #3

Because you are keeping 13 months of phone call data and want to easily drop the oldest month every 1st. Because your queries need to be fast, and you can chop up your data into 1000 pieces (by some column or combination) without adding complexity.

You can easily drop the oldest month every 1st using a delete statement.

Queries can be fast with indexes without adding complexity.