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From:daniel Date:November 11 2002 1:51am
Subject:RE: MySql 4.1 Sub Selects
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will 4.1 hopefully have stored procedure functionality ?

>===== Original Message From "Greg Matthews" <greg55@stripped> =====
>With the efficiency comment below, I was using the strategy that I'd prefer
>to wait for 4.1's impending (?) release rather than rewrite SQL in a
>workaround way. It's a tradeoff based on our specific project and relating
>to time factors, etc, and the amount of SQL I'd have to rewrite.
>
>Yes i'm sure the hurdle could be overcome but I'd rather hold back on MySql
>support until subselect functionality is ready.
>
>
>Typically, database vendors seem to recommend using EXISTS because the query
>returns on finding the first row that meets whatever the subselect criteria
>is.
>
>Do those people working on 4.1 anticipate the performance of the MySql sub
>select functionality to be better than an equivalent query written as a
>join? I guess any answer to this should also include consideration of
>sometimes putting DISTINCT in the select statement.
>
>Thanks a lot,
>Greg.
>
>----- Original Message -----
>From: "Michael T. Babcock" <mbabcock@stripped>
>To: "Greg Matthews" <greg55@stripped>
>Cc: <mysql@stripped>
>Sent: Monday, November 11, 2002 11:16 AM
>Subject: Re: MySql 4.1 Sub Selects
>
>
>> Greg Matthews wrote:
>>
>> >clause) instead of EXISTS -- seems like a "tail wagging the dog"
>strategy.
>> >Isn't EXISTS a lot more efficient than an inner join?
>> >
>>
>> Well, its more efficient if it exists, I guess ... but if it doesn't
>> exist on your platform (MySQL), then its pretty inefficient, really.
>>
>> >We're going to offering the application on Oracle and so I wouldn't like
>to
>> >de-optimize the SQL just so it works on mysql 4.0 if 4.1 will be out
>within
>> >a few months.
>> >
>>
>> If you're writing OO code, you might be able to easily flag your objects
>> as to whether to use one or the other query based on the underlying
>> database system (queried at run-time).
>>
>> --
>> Michael T. Babcock
>> C.T.O., FibreSpeed Ltd.
>> http://www.fibrespeed.net/~mbabcock
>>
>>
>
>
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Thread
MySql 4.1 Sub SelectsGreg Matthews10 Nov
  • Re: MySql 4.1 Sub SelectsJeremy Zawodny10 Nov
  • Re: MySql 4.1 Sub SelectsGreg Matthews10 Nov
    • Re: MySql 4.1 Sub SelectsJeremy Zawodny10 Nov
  • Re: MySql 4.1 Sub SelectsJocelyn Fournier10 Nov
  • Re: MySql 4.1 Sub SelectsGreg Matthews10 Nov
    • Re: MySql 4.1 Sub SelectsJeremy Zawodny10 Nov
  • Re: MySql 4.1 Sub SelectsHarald Fuchs10 Nov
  • Re: MySql 4.1 Sub SelectsGreg Matthews10 Nov
  • Re: MySql 4.1 Sub SelectsMichael T. Babcock11 Nov
  • Re: MySql 4.1 Sub SelectsGreg Matthews11 Nov
RE: MySql 4.1 Sub Selectsdaniel11 Nov
  • re: RE: MySql 4.1 Sub SelectsVictoria Reznichenko11 Nov
    • RE: RE: MySql 4.1 Sub SelectsDan Rossi11 Nov
      • Re: RE: MySql 4.1 Sub Selects and not stored proceduresGreg Matthews11 Nov
        • RE: RE: MySql 4.1 Sub Selects and not stored proceduresArthur Fuller11 Nov
          • Re: RE: MySql 4.1 Sub Selects and not stored proceduresGreg Matthews11 Nov
        • Re: MySql 4.1 Sub Selects and not stored proceduresDan Nelson11 Nov
        • Re: RE: MySql 4.1 Sub Selects and not stored proceduresJohn Ragan11 Nov
      • Re: MySql 4.1 Sub SelectsMichael T. Babcock11 Nov
re[2]: MySql 4.1 Sub SelectsRichard Morton11 Nov
  • Re: re[2]: MySql 4.1 Sub SelectsLenz Grimmer11 Nov