Re: [ADMIN] Processing very large TEXT columns (300MB+) using C/libpq

Yes, but I should be able to read them much faster.  The psql client can display an 11MB column in a little over a minute, while in C using libpg library, it takes over an hour.  

Anyone have any experience with the same issue that can help me resolve?

--cnemelka

On Thu, Oct 19, 2017 at 5:20 PM, Aldo Sarmiento <aldo@bigpurpledot.com> wrote:

I believe large columns get put into a TOAST table. Max page size is 8k. So you'll have lots of pages per row that need to be joined with a size like that: https://www.postgresql.org/docs/9.5/static/storage-toast.html

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On Thu, Oct 19, 2017 at 2:03 PM, Cory Nemelka <cnemelka@gmail.com> wrote:

I have getting very poor performance using libpq to process very large TEXT columns (300MB+).   I suspect it is IO related but can't be sure.

Anyone had experience with same issue that can help me resolve?

--cnemelka