BOp
s using the UNION of JOINs. However, also note that
this is only used for TM and that the focus store is always local
for TM.public class AccessPathFusedView<E> extends Object implements IAccessPath<E>
IPredicate
constraint in two different databases (this is used for
truth maintenance when reading on the union of a focus store and the
database).
FIXME review impl and write tests.
FIXME Does not support IPredicate.Annotations#ACCESS_PATH_FILTER
Modifier and Type | Field and Description |
---|---|
protected static org.apache.log4j.Logger |
log
Deprecated.
|
Constructor and Description |
---|
AccessPathFusedView(AccessPath<E> path1,
AccessPath<E> path2)
Deprecated.
|
Modifier and Type | Method and Description |
---|---|
IIndex |
getIndex()
Deprecated.
The index selected for the access path.
|
IKeyOrder<E> |
getKeyOrder()
Deprecated.
The order in which the elements will be visited.
|
IPredicate<E> |
getPredicate()
Deprecated.
The constraints on the
IAccessPath . |
boolean |
isEmpty()
Deprecated.
True iff the access path is empty (there are no matches for the
IPredicate ) This is more conclusive than #rangeCount()
since you MAY have a non-zero range count when the key range is in fact
empty (there may be "deleted" index entries within the key range). |
IChunkedOrderedIterator<E> |
iterator()
Deprecated.
An iterator visiting elements using the natural order of the index
selected for the
IPredicate . |
IChunkedOrderedIterator<E> |
iterator(long offset,
long limit,
int capacity)
Deprecated.
FIXME write tests for optimizations for point tests and small limits.
|
long |
rangeCount(boolean exact)
Deprecated.
Return the maximum #of elements spanned by the
IPredicate . |
long |
removeAll()
Deprecated.
Remove all elements selected by the
IPredicate (optional
operation). |
public AccessPathFusedView(AccessPath<E> path1, AccessPath<E> path2)
public IPredicate<E> getPredicate()
IAbstractAccessPath
IAccessPath
.getPredicate
in interface IAbstractAccessPath<E>
public boolean isEmpty()
IAbstractAccessPath
IPredicate
) This is more conclusive than #rangeCount()
since you MAY have a non-zero range count when the key range is in fact
empty (there may be "deleted" index entries within the key range).isEmpty
in interface IAbstractAccessPath<E>
public long rangeCount(boolean exact)
IPredicate
.
Note: When there is an IFilter
on the IPredicate
the
exact range count MUST apply that IFilter
, which means that it
will be required to traverse the index counting tuples which pass the
IFilter
. However, IFilter
s are ignored for the fast
range count.
Note: You can not get an exact range count for a view.
rangeCount
in interface IAbstractAccessPath<E>
exact
- When true
, the result will be an exact count and
may require a key-range scan. When false
, the
result will be an upper bound IFF delete markers are
provisioned for the backing index (delete markers are required
for transactions and for scale-out indices).UnsupportedOperationException
- if exact == true
.IRangeQuery
public IIndex getIndex()
Note: The access path may incorporate additional constraints from the
specified IPredicate
that are not present on the IIndex
returned by this method.
getIndex
in interface IAccessPath<E>
UnsupportedOperationException
- always.public IChunkedOrderedIterator<E> iterator()
IAccessPath
IPredicate
. This is equivalent to
iterator(0L, 0L, 0)since an offset of ZERO (0L) means no offset, a limit of ZERO (0L) means no limit and a capacity of ZERO (0) means whatever is the default capacity.
Note: Filters should be specified when the IAccessPath
is
constructed so that they will be evaluated on the IDataService
rather than materializing the elements and then filtering then. This can
be accomplished by adding the filter as an IElementFilter
on the
IPredicate
when requesting IAccessPath
.
iterator
in interface IAccessPath<E>
IRelation.getAccessPath(IPredicate)
public IChunkedOrderedIterator<E> iterator(long offset, long limit, int capacity)
iterator
in interface IAccessPath<E>
offset
- The first element accepted by the iterator that it will visit
(materialize for the client). The offset must be non-negative.
This is ZERO (0L) to visit all accepted elements.limit
- The last element accepted by the iterator that it will visit
(materialize for the client). The limit must be non-negative.
This is ZERO (0L) to visit all accepted elements (the value
Long.MAX_VALUE
is interpreted exactly like ZERO(0L)).capacity
- The maximum capacity for the buffer used by the iterator. When
ZERO(0), a default capacity will be used. When a limit
is specified, the capacity will never exceed the limit.IAccessPath
. This way they
will be correctly applied when IAbstractAccessPath.isEmpty()
is implemented
using the IAccessPath.iterator()
to determine if any elements can be
visited.public long removeAll()
IAbstractAccessPath
IPredicate
(optional
operation).removeAll
in interface IAbstractAccessPath<E>
public IKeyOrder<E> getKeyOrder()
IAccessPath
getKeyOrder
in interface IAccessPath<E>
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