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create table toast (
description text,
data text
);
insert into toast values ('short inline', 'xxx');
insert into toast values ('long inline uncompressed', repeat('x', 200));
alter table toast alter column data set storage external;
insert into toast values ('external uncompressed', repeat('0123456789 8< ', 200));
alter table toast alter column data set storage extended;
insert into toast values ('inline compressed pglz', repeat('0123456789 8< ', 200));
insert into toast values ('extended compressed pglz', repeat('0123456789 8< ', 20000));
alter table toast alter column data set compression lz4;
insert into toast values ('inline compressed lz4', repeat('0123456789 8< ', 200));
insert into toast values ('extended compressed lz4', repeat('0123456789 8< ', 50000));
select description, pg_column_size(data), substring(data, 1, 50) as data from toast;
delete from toast;
-- toasted values are uncompressed after pg_dirtyread
select description, pg_column_size(data), substring(data, 1, 50) as data from pg_dirtyread('toast') as (description text, data text);
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