Arrays and "goodness" in RDBMSs (was Re: join of array)
От | Ron Johnson |
---|---|
Тема | Arrays and "goodness" in RDBMSs (was Re: join of array) |
Дата | |
Msg-id | 1060971232.4580.379.camel@haggis обсуждение исходный текст |
Ответ на | Re: join of array (Joe Conway <mail@joeconway.com>) |
Ответы |
Re: Arrays and "goodness" in RDBMSs (was Re: join of array)
Re: Arrays and "goodness" in RDBMSs (was Re: join of array) |
Список | pgsql-general |
On Fri, 2003-08-15 at 12:41, Joe Conway wrote: > Tom Lane wrote: > > That's about as clear as mud :-( ... but I found a clearer statement > > in SQL99 6.31: > > > > 2) If <array concatenation> is specified, then: > > > > a) Let AV1 be the value of <array value expression 1> and let AV2 be > > the value of <array value expression 2>. > > > > b) If either AV1 or AV2 is the null value, then the result of the > > <array concatenate function> is the null value. > > > > c) Otherwise, the result is the array comprising every element of AV1 > > followed by every element of AV2. > > > > (c) seems to be pretty clearly what Pavel wants for the 1-D case, but > > it's not immediately clear how to apply it to multidimensional > > arrays. > > > > Thanks -- I found the corresponding paragraph in SQL200x (6.35) and it > pretty much reads the same. Why are arrays even mentioned in the the same breath wrt relations DBMSs? Aren't they an anathema to all we know and love? -- +---------------------------------------------------------------+ | Ron Johnson, Jr. Home: ron.l.johnson@cox.net | | Jefferson, LA USA | | | | "Man, I'm pretty. Hoo Hah!" | | Johnny Bravo | +---------------------------------------------------------------+
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