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Thread: Strange Index sizes

Strange Index sizes

From
Mohsen Bande
Date:
Hi all,
I have a user table with ~8M records, with different type of fields b-tree indexed.
by investigating index sizes, i found two strange things:
1- all index sizes are almost the same, regardless of field type (boolean, string, bigint)
2 - all of them are much bigger that my expectation, e.g. for a boolean field, even after reindexing, the size is 217MB, so each record takes ~27 bytes.

could some one shed some light on this please? or refer any user oriented documentation about index size estimations

Re: Strange Index sizes

From
Adrian Klaver
Date:
On 04/24/2018 11:41 PM, Mohsen Bande wrote:
> Hi all,
> I have a user table with ~8M records, with different type of fields 
> b-tree indexed.

Could we see table schema and index statements?

> by investigating index sizes, i found two strange things:
> 1- all index sizes are almost the same, regardless of field type 
> (boolean, string, bigint)

What was the command you used to determine the sizes?

> 2 - all of them are much bigger that my expectation, e.g. for a boolean 
> field, even after reindexing, the size is 217MB, so each record takes 
> ~27 bytes.
> 
> could some one shed some light on this please? or refer any user 
> oriented documentation about index size estimations


-- 
Adrian Klaver
adrian.klaver@aklaver.com