public class RewriteGBUsingIndex extends java.lang.Object implements Transform
select count(key)
from table
group by key;
to
select sum(_count_of_key)
from idx_table
group by key;
The rewrite supports following queries:
Constructor and Description |
---|
RewriteGBUsingIndex() |
Modifier and Type | Method and Description |
---|---|
ParseContext |
transform(ParseContext pctx)
All transformation steps implement this interface.
|
public ParseContext transform(ParseContext pctx) throws SemanticException
Transform
transform
in interface Transform
pctx
- input parse contextSemanticException
Copyright © 2012 The Apache Software Foundation