Re: MV Keys
From: Marshall Spight <marshall.spight_at_gmail.com>
Date: 2 Mar 2006 23:59:41 -0800
Message-ID: <1141372781.078243.197630_at_e56g2000cwe.googlegroups.com>
> As long as the type of a bunch of values is well-defined, there is
> indeed no problem---indeed, that makes the two alternatives I outlined
> equivalent. However, if any attribute is a set (or list), you probably
> want (for convenience) to treat it as a single value of its constituent
> type when it contains only one value, I.e. "Jon" = { "Jon" }. A language
> that does this may exhibit undesirable behaviour in other places; I
> believe SQL has trouble with table literals because of this.
Date: 2 Mar 2006 23:59:41 -0800
Message-ID: <1141372781.078243.197630_at_e56g2000cwe.googlegroups.com>
Jon Heggland wrote:
>
> As long as the type of a bunch of values is well-defined, there is
> indeed no problem---indeed, that makes the two alternatives I outlined
> equivalent. However, if any attribute is a set (or list), you probably
> want (for convenience) to treat it as a single value of its constituent
> type when it contains only one value, I.e. "Jon" = { "Jon" }. A language
> that does this may exhibit undesirable behaviour in other places; I
> believe SQL has trouble with table literals because of this.
Can you say more about this? What kind of trouble?
Marshall Received on Fri Mar 03 2006 - 08:59:41 CET