Re: Checking for username...

Ivan Omelchenko 608308824 wrote:

> Kenneth Downs ?????:
>> Domestos wrote:
>>
>>
>>>Hi all,
>>>
>>>How do I check in a mySQL table called 'Users' on column user_name when
>>>registering a new user_name to make sure the new 'user_name' does not
>>>already exist in that column?
>>>
>>>TIA
>>
>>
>> The database can do this by implementing a unique constraint on the
>> column
>> user_name. After issuing the INSERT, (or any SQL command), check for an
>> error, and report it. This then solves your general problem of enforcing
>> data integrity and reporting errors.
> checking for the SQL error is not a good idea, actually.
> Well known programing prupose to use select before insert.

Well known on what planet?

The Server maintains integrity, that's why they were invented. This
protects the database against a buggy or intentionally misbehaving
application. Not surprisingly, it is also much faster.

--
Kenneth Downs
Secure Data Software, Inc.
(Ken)nneth@(Sec)ure(Dat)a(.com)
.

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