Re: Re: Re: Re (tilly) 4: How NOT to do it

It's that queries cannot be recursive. Of course, there have been a number of papers popping up here and there about Turing-complete SQL extensions.

I can see how recursive queries could get rediculous, but why prevent that ability? Is it dangerous? Does it violate DB 'best practices'?

I don't know much of anything about DB internals, or even the interfaces, so I'm groping here.

*sigh* I just used a PHBism. Where's that lobotamy brochure?

Perl programming and scheduling in the corporate world, as explained by dragonchild:

"Uhh ... that'll take me three weeks, broken down as follows: 1 day for coding, the rest for meetings to explain why I only need 1 day for coding."

Comment on Re: Re: Re: Re (tilly) 4: How NOT to do it

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Re: Re: Re: Re: Re (tilly) 4: How NOT to do it by antirice (Priest) on Sep 11, 2003 at 06:19 UTC
The reason is pretty simple: a database is a place to store and retrieve data. Creation of data is not up to the database. The database stores data and you ask it to present a relational view of the data stored based upon certain parameters. Regardless of how you relate the tables in your sql statement, you will get a finite amount of data back. Just for a wonderful nightmare, imagine a select statement that recursively inserted into the same table that it was selecting from. Of course, the fact that the database will return a finite amount of data is somewhat nice in my opinion. Hope this helps. If I made no sense, it's because I've been up for more than 24 hours :-/ antirice The first rule of Perl club is - use Perl The ith rule of Perl club is - follow rule i - 1 for i > 1	[reply]

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Re: Re: Re: Re: Re (tilly) 4: How NOT to do it
by antirice (Priest) on Sep 11, 2003 at 06:19 UTC

The reason is pretty simple: a database is a place to store and retrieve data. Creation of data is not up to the database. The database stores data and you ask it to present a relational view of the data stored based upon certain parameters. Regardless of how you relate the tables in your sql statement, you will get a finite amount of data back. Just for a wonderful nightmare, imagine a select statement that recursively inserted into the same table that it was selecting from. Of course, the fact that the database will return a finite amount of data is somewhat nice in my opinion.

Hope this helps. If I made no sense, it's because I've been up for more than 24 hours :-/

antirice
The first rule of Perl club is - use Perl
The ith rule of Perl club is - follow rule i - 1 for i > 1

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