Re: [HACKERS] Custom compression methods

On 11/21/2017 09:28 PM, Ildus K wrote:
>> Hmmm, it still doesn't work for me. See this:
>>
>> test=# create extension pg_lz4 ;
>> CREATE EXTENSION
>> test=# create table t_lz4 (v text compressed lz4);
>> CREATE TABLE
>> test=# create table t_pglz (v text);
>> CREATE TABLE
>> test=# insert into t_lz4 select repeat(md5(1::text),300);
>> INSERT 0 1
>> test=# insert into t_pglz select * from t_lz4;
>> INSERT 0 1
>> test=# drop extension pg_lz4 cascade;
>> NOTICE: drop cascades to 2 other objects
>> DETAIL: drop cascades to compression options for lz4
>> drop cascades to table t_lz4 column v
>> DROP EXTENSION
>> test=# \c test
>> You are now connected to database "test" as user "user".
>> test=# insert into t_lz4 select repeat(md5(1::text),300);^C
>> test=# select * from t_pglz ;
>> ERROR: cache lookup failed for compression options 16419
>>
>> That suggests no recompression happened.
>
> I will check that. Is your extension published somewhere?
>

No, it was just an experiment, so I've only attached it to the initial
review. Attached is an updated version, with a fix or two.

regards

--
Tomas Vondra http://www.2ndQuadrant.com
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