[
https://issues.apache.org/jira/browse/PHOENIX-1211?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14122215#comment-14122215
]
James Taylor commented on PHOENIX-1211:
---------------------------------------
Yep, you're right. The places where we increment the position array needs to
take into account the slotSpan array instead of assuming the increment is
always +1. You'd increment by slotSpan[i]+1 instead:
{code}
private int nextPosition(int i) {
while (i >= 0 && slots.get(i).get(position[i]).isSingleKey() &&
(position[i] = (position[i] + 1) % slots.get(i).size()) == 0) {
i--; // TODO: use slotSpan to decrement
}
return i;
}
{code}
{code}
private int previousPosition(int i) {
while (i >= 0 && --position[i] < 0) {
position[i] = slots.get(i).size()-1;
i--; // TODO: use slotSpan to decrement
}
return i;
}
{code}
In navigate:
{code}
// If we're positioned at a single key, no need to copy the
current key and get the next key .
// Instead, just increment to the next key and continue.
boolean incremented = false;
while (j >= 0 && slots.get(j).get(position[j]).isSingleKey() &&
(incremented=true) && (position[j] = (position[j] + 1) % slots.get(j).size())
== 0) {
j--; // TODO: use slotSpan to decrement
incremented = false;
}
{code}
And yes, it'd be nice to have a single nextPosition() and previousPosition()
method, but it's tough b/c we depend on some extra state sometimes. Maybe see
if the above fixes the current issue and if so, think about this one to see
what you can come up with?
> Use skip scan when row value constructor uses leading row key columns
> ----------------------------------------------------------------------
>
> Key: PHOENIX-1211
> URL: https://issues.apache.org/jira/browse/PHOENIX-1211
> Project: Phoenix
> Issue Type: Bug
> Reporter: James Taylor
> Assignee: Kyle Buzsaki
> Attachments: PHOENIX-1211-diff.patch
>
>
> We currently only use a skip scan for a row value constructor equality or in
> list expression is fully qualified. We can fairly easily use it when only
> some of the leading pk columns are used.
> For example:
> {code}
> WHERE (a,b) IN ((1,2),(3,4))
> {code}
> If the PK is (a,b,c), we can still use a skip scan. We need to pass through
> the slotSpan array in this case too, to the SkipScanFilter.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
