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From Rick Hillegas <Richard.Hille...@Sun.COM>
Subject Re: Collation implementation WAS Re: Should COLLATION attribute related code go in BasicDatabase?
Date Thu, 15 Mar 2007 15:50:44 GMT
Daniel John Debrunner wrote:
> ...
>
> - The collation type (the integer) is written into the meta-data for 
> an index just as ascending/descending is today (including the btree 
> control row, thus making the information available for recovery). 
> Collation type applies to all character columns in the index.
>
This suggests that all of the columns in the index must have the same 
collation? I don't think that is powerful enough to support the 
full-blown SQL collation language, which allows you to mix differently 
collated columns in an ORDER BY clause. Why can't the collation type be 
an array of ints just as the sort direction is an array of booleans in 
IndexDescriptor?



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