org.tikv.common.expression

Class RangePartitionPruner

java.lang.Object

org.tikv.common.expression.RangePartitionPruner

public class RangePartitionPruner
extends Object

Method Summary

Modifier and Type	Method and Description
boolean	canBePruned(Expression filter) return false if table cannot be pruning or partition table is not enabled.
List<TiPartitionDef>	prune(List<Expression> filters) When table is a partition table and its type is range.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

prune

public List<TiPartitionDef> prune(List<Expression> filters)

When table is a partition table and its type is range. We use this method to do the pruning. Range partition has two types: 1. range 2. range column. If it is the first case, pruneRangeNormalPart will be called. Otherwise pruneRangeColPart will be called. For now, we simply skip range column partition case.

Parameters:

filters - is where condition belong to a select statement.

Returns:

a pruned partition for scanning.

canBePruned

public boolean canBePruned(Expression filter)

return false if table cannot be pruning or partition table is not enabled. Return true if partition pruning can be applied.

Parameters:

filter - is a where condition. It must be a cnf and does not contain not or isnull.

Returns:

true if partition pruning can apply on filter.