Re: efficiency random values / sequential ID values in indexes

Thanks

On Mon, Apr 15, 2024 at 6:19 PM Ron Johnson <ronljohnsonjr(at)gmail(dot)com> wrote:

> On Mon, Apr 15, 2024 at 6:05 AM Sanjay Minni <sanjay(dot)minni(at)gmail(dot)com>
> wrote:
>
>> Hi
>>
>> Is there any appreciable difference in using random values or sequential
>> values in indexes
>>
>> in a multi tenanted application there is a choice that the single field
>> ID's value is totally random / UUID or the numbers are created with a
>> prefix of the tenant. Since all access will be within a tenant only, will
>> it make any performance difference between using purely random values vs
>> <tenant no prefix part>+<random value>.
>>
>
> Two benefits of <tenant no prefix part>+<random value>:
>
> 1. In a non-partitioned table, it gives your index "locality of data":
> all of customer X's record pointers are in *This* subtree. Makes buffers
> more efficient when a customer runs reports. Bonus points if you then
> regularly CLUSTER using that table.
> 2. Makes table partitioning by <tenant prefix> much easier. That also
> enhances locality of data.
>
> Just make sure that the field ID is BIGINT...
>