Subject: Re: PostgreSQL CHARACTER VARYING vs CHARACTER VARYING (Length)
To: pgsql-admin@lists.postgresql.org
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From: Holger Jakobs <holger@jakobs.com>
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Date: Tue, 28 Apr 2020 17:10:31 +0200
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Truncation will NEVER happen. PostgreSQL throws an ERROR on any attempt 
of saving more characters (not bytes!) into a VARCHAR(50) column.

There is some other well-known system which silently truncates, but we 
all know why we would never use that.

Am 28.04.20 um 13:46 schrieb Ashutosh Bapat:
> On Tue, Apr 28, 2020 at 2:53 PM Rajin Raj <rajin.raj@opsveda.com> wrote:
>> Is there any impact of using the character varying without providing the length while creating tables?
>> I have created two tables and inserted 1M records. But I don't see any difference in pg_class. (size, relpage)
>>
>> create table test_1(name varchar);
>> create table test_2(name varchar(50));
> I don't think there's a difference in the way these two are stored
> on-disk. But if you know that your strings will be at most 50
> characters long, better set that limit so that server takes
> appropriate action (i.e. truncates the strings to 50).
>
-- 
Holger Jakobs, Bergisch Gladbach, Tel. +49-178-9759012