Daniel John Debrunner wrote:
Rick Hillegas wrote:
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?
That would be more flexible, but is it required? Is an order by that
spills to disk implemented using a BTREE?
No, order by that spills to disk is implemented by the sorter.
Thanks,
Dan.
