On Fri, 5 Jul 2024 at 17:07, Lok P <loknath...@gmail.com> wrote:
> Also I understand the technical limitation of the max number of columns per
> table is ~1600. But should you advise to restrict/stop us to some low number
> long before reaching that limit , such that we will not face any anomalies
> when we grow in future. And if we should maintain any specific order in the
> columns from start to end column in the specific table?
Something else you may wish to consider, depending on the column types
of your 900+ columns is the possibility that some INSERTs may fail due
to row length while others with shorter variable length values may be
ok.
Here's a quick example with psql:
select 'create table a (' || string_agg('a'||x||' text not null
default $$$$',',') || ')' from generate_series(1,1000)x;
\gexec
insert into a default values;
INSERT 0 1
again but with a larger DEFAULT to make the tuple larger.
select 'create table b (' || string_agg('a'||x||' text not null
default $$hello world$$',',') || ')' from generate_series(1,1000)x;
\gexec
insert into b default values;
ERROR: row is too big: size 12024, maximum size 8160
There is a paragraph at the bottom of [1] with some warnings about
things relating to this.
The tuple length would be fixed for fixed-length types defined as NOT
NULL. So, if you have that, there should be no such surprises.
David
[1] https://www.postgresql.org/docs/current/limits.html
