Re: Converting char to varchar automatically

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От Jim Nasby
Тема Re: Converting char to varchar automatically
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Msg-id 54331525.5000708@BlueTreble.com
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Ответ на Re: Converting char to varchar automatically  (hari.fuchs@gmail.com)
Ответы Re: Converting char to varchar automatically  (Melvin Davidson <melvin6925@gmail.com>)
Re: Converting char to varchar automatically  (Tom Lane <tgl@sss.pgh.pa.us>)
Список pgsql-general
On 10/6/14, 12:41 PM, hari.fuchs@gmail.com wrote:
> Melvin Davidson <melvin6925@gmail.com> writes:
>
>> This query might work for you, but double check all result statements first.
>>
>> SELECT 'ALTER TABLE ' || quote_ident(n.nspname) || '.' ||
>> quote_ident(c.relname)
>>         || ' ALTER COLUMN ' || quote_ident(a.attname) || ' TYPE varchar;'
>>    FROM pg_class c
>>    JOIN pg_namespace n ON n.oid = c.relnamespace
>>    JOIN pg_attribute a ON a.attrelid = c.oid
>>    JOIN pg_type t ON t.oid = a.atttypid
>>   WHERE t.typname = 'char'
>>     AND n.nspname <> 'pg_catalog';
> Make that "t.typname = 'bpchar'".
>
Just a heads-up: each of those ALTER's will rewrite the table, so unless your database is tiny this will be a slow
process.There's ways to work around that, but they're significantly more complicated. 

--
Jim Nasby, Data Architect, Blue Treble
Data in Trouble? Get it in Treble! http://BlueTreble.com



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