Re: Fwd: TOAST table performance problem

From: Luís Roberto Weck <luisroberto(at)siscobra(dot)com(dot)br>
To: ayisan1096(at)gmail(dot)com
Cc: pgsql-performance(at)lists(dot)postgresql(dot)org
Subject: Re: Fwd: TOAST table performance problem
Date: 2020-02-10 12:31:30
Message-ID: f3baba0f-e6c1-af73-e25e-49abcabb3ab7@siscobra.com.br
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

> ---------- Forwarded message ---------
> Gönderen: *Asya Nevra Buyuksoy* <ayisan1096(at)gmail(dot)com
> <mailto:ayisan1096(at)gmail(dot)com>>
> Date: 10 Şub 2020 Pzt, 10:51
> Subject: Re: TOAST table performance problem
> To: Andreas Joseph Krogh <andreas(at)visena(dot)com <mailto:andreas(at)visena(dot)com>>
>
>
> I copied my data to the CSV file, yes it is very fast. However, this
> does not solve my problem.
> After deserializing the on the front side, I want to visualize my data
> on the web page effectively.
> When I select my data one by one with a limit clause, the query
> executes 200 ms. For example, If I create a function that takes data
> with a loop, the execution time will be 200 ms*1000=200 sec.
>
> Andreas Joseph Krogh <andreas(at)visena(dot)com <mailto:andreas(at)visena(dot)com>>,
> 7 Şub 2020 Cum, 18:15 tarihinde şunu yazdı:
>
> Try \o <filename> in psql, to redirect the output to file, and
> prevent it from processing the json (ie. format it)
>
> Den 7. februar 2020 15:59:05 CET, skrev Asya Nevra Buyuksoy
> <ayisan1096(at)gmail(dot)com <mailto:ayisan1096(at)gmail(dot)com>>:
>
> I try it, but there is no enhancement.
> I read this link is about TOAST and also its sub_links;
> https://blog.gojekengineering.com/a-toast-from-postgresql-83b83d0d0683
>
> When I execute this query, except JSON data like;
> SELECT paramuser_id, paramperson_id, paramisdeleted,
> paramactiontime
>   FROM zamazin;
> It takes 94 ms. :)
>
>
> Andreas Joseph Krogh <andreas(at)visena(dot)com
> <mailto:andreas(at)visena(dot)com>>, 7 Şub 2020 Cum, 17:42 tarihinde
> şunu yazdı:
>
> På fredag 07. februar 2020 kl. 15:35:04, skrev Asya Nevra
> Buyuksoy <ayisan1096(at)gmail(dot)com <mailto:ayisan1096(at)gmail(dot)com>>:
>
> I use pgadmin3.
>
> Try "psql", it has the lowest overhead (I think). pgAdmin
> might use time presenting the results etc. which is easy
> to overlook.
> --
> Andreas Joseph Krogh
>
>
> --
> Sendt fra min Android-enhet med K-9 e-post. Unnskyld min
> kortfattethet.
>

What Andreas is trying to say is that it's not PostgreSQL that is slow
to read the JSON, but your client app that is slow to parse it.

In response to

Responses

Browse pgsql-performance by date

  From Date Subject
Next Message Asya Nevra Buyuksoy 2020-02-10 12:38:17 Re: Fwd: TOAST table performance problem
Previous Message Chris Borckholder 2020-02-10 10:34:01 Bad selectivity estimate when using a sub query to determine WHERE condition