Re: Need suggestion on how best to update 3 million rows

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On 09/06/07 04:20, Ow Mun Heng wrote:
> On Thu, 2007-09-06 at 04:07 -0500, Ron Johnson wrote:
>
>> On 09/06/07 01:13, Ow Mun Heng wrote:
>
>>> update org_column set number = foo.number where foo.unique_id =
>>> org_column=unique_id.
>> Number? Where does "number" come from? Unless you've got weird
>> field names, that doesn't sound like a very good name for a
>> VARCHAR(4) column.
>
> "number" is just a fictitious column name. I use sane column names of
> course :-)

OK.

Maybe there's an English language "issue", or maybe I'm just
excessively picky, but using "number" in this context is confusing.

In any event, it didn't stop the Earth from spinning or the sun from
shining, so it can't be that bad of a problem...

>>> The update is taking a few hours and still hasn't ended.
>>>
>
>> Is it only *some* tuples that have the "extra space" problem?
>
> Actually, it's all of it

Then I agree with Alban:
update table set number = trim(number);
or, if you need the leading spaces:
update table set number = rtrim(number)

Then:
update table set number = NULL where number = '';

- --
Ron Johnson, Jr.
Jefferson LA USA

Give a man a fish, and he eats for a day.
Hit him with a fish, and he goes away for good!

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