org.h2.index

Class ViewIndex

java.lang.Object

org.h2.engine.DbObjectBase

org.h2.schema.SchemaObjectBase

org.h2.index.BaseIndex

org.h2.index.ViewIndex

All Implemented Interfaces:

DbObject, Index, SpatialIndex, SchemaObject

public class ViewIndex
extends BaseIndex
implements SpatialIndex

This object represents a virtual index for a query. Actually it only represents a prepared SELECT statement.

Field Summary

Fields inherited from class org.h2.index.BaseIndex

columnIds, columns, indexColumns, indexType, isMultiVersion, table

Fields inherited from class org.h2.engine.DbObjectBase

comment, database, trace

Fields inherited from interface org.h2.engine.DbObject

AGGREGATE, COMMENT, CONSTANT, CONSTRAINT, FUNCTION_ALIAS, INDEX, RIGHT, ROLE, SCHEMA, SEQUENCE, SETTING, SYNONYM, TABLE_OR_VIEW, TRIGGER, USER, USER_DATATYPE

Constructor Summary

Constructors

Constructor and Description
ViewIndex(TableView view, java.lang.String querySQL, java.util.ArrayList<Parameter> originalParameters, boolean recursive) Constructor for the original index in TableView.
ViewIndex(TableView view, ViewIndex index, Session session, int[] masks, TableFilter[] filters, int filter, SortOrder sortOrder) Constructor for plan item generation.

Method Summary

Modifier and Type	Method and Description
void	add(Session session, Row row) Add a row to the index.
boolean	canGetFirstOrLast() Check if the index can directly look up the lowest or highest value of a column.
void	checkRename() Check if this object can be renamed.
void	close(Session session) Close this index.
IndexLookupBatch	createLookupBatch(TableFilter[] filters, int filter) Creates new lookup batch.
Cursor	find(Session session, SearchRow first, SearchRow last) Find a row or a list of rows and create a cursor to iterate over the result.
Cursor	findByGeometry(TableFilter filter, SearchRow first, SearchRow last, SearchRow intersection) Find a row or a list of rows and create a cursor to iterate over the result.
Cursor	findFirstOrLast(Session session, boolean first) Find the first (or last) value of this index.
double	getCost(Session session, int[] masks, TableFilter[] filters, int filter, SortOrder sortOrder, java.util.HashSet<Column> allColumnsSet) Estimate the cost to search for rows given the search mask.
long	getDiskSpaceUsed() Get the used disk space for this index.
java.lang.String	getPlanSQL() Get the message to show in a EXPLAIN statement.
Query	getQuery()
long	getRowCount(Session session) Get the row count of this table, for the given session.
long	getRowCountApproximation() Get the approximated row count for this table.
Session	getSession()
boolean	isExpired()
boolean	isRecursive()
boolean	needRebuild() Check if the index needs to be rebuilt.
void	remove(Session session) Remove the index.
void	remove(Session session, Row row) Remove a row from the index.
void	setRecursive(boolean value)
void	setupQueryParameters(Session session, SearchRow first, SearchRow last, SearchRow intersection) Set the query parameters.
void	truncate(Session session) Remove all rows from the index.

Methods inherited from class org.h2.index.BaseIndex

canFindNext, canScan, checkIndexColumnTypes, commit, compareRows, find, findNext, getColumnIndex, getColumns, getCostRangeIndex, getCreateSQL, getCreateSQLForCopy, getDropSQL, getDuplicateKeyException, getIndexColumns, getIndexType, getRow, getTable, getType, initBaseIndex, isFindUsingFullTableScan, isFirstColumn, isHidden, isRowIdIndex, mayHaveNullDuplicates, removeChildrenAndResources, setSortedInsertMode

Methods inherited from class org.h2.schema.SchemaObjectBase

getSchema, getSQL, initSchemaObjectBase

Methods inherited from class org.h2.engine.DbObjectBase

getChildren, getComment, getDatabase, getId, getModificationId, getName, initDbObjectBase, invalidate, isTemporary, isValid, rename, setComment, setModified, setObjectName, setTemporary, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.h2.index.Index

canFindNext, canScan, commit, compareRows, find, findNext, getColumnIndex, getColumns, getIndexColumns, getIndexType, getRow, getTable, isFindUsingFullTableScan, isFirstColumn, isRowIdIndex, setSortedInsertMode

Methods inherited from interface org.h2.schema.SchemaObject

getSchema, isHidden

Methods inherited from interface org.h2.engine.DbObject

getChildren, getComment, getCreateSQL, getCreateSQLForCopy, getDatabase, getDropSQL, getId, getName, getSQL, getType, isTemporary, removeChildrenAndResources, rename, setComment, setTemporary

Constructor Detail

ViewIndex

public ViewIndex(TableView view,
                 java.lang.String querySQL,
                 java.util.ArrayList<Parameter> originalParameters,
                 boolean recursive)

Constructor for the original index in TableView.

Parameters:

view - the table view

querySQL - the query SQL

originalParameters - the original parameters

recursive - if the view is recursive

ViewIndex

public ViewIndex(TableView view,
                 ViewIndex index,
                 Session session,
                 int[] masks,
                 TableFilter[] filters,
                 int filter,
                 SortOrder sortOrder)

Constructor for plan item generation. Over this index the query will be executed.

Parameters:

view - the table view

index - the view index

session - the session

masks - the masks

filters - table filters

filter - current filter

sortOrder - sort order

Method Detail

createLookupBatch

public IndexLookupBatch createLookupBatch(TableFilter[] filters,
                                          int filter)

Description copied from interface: Index

Creates new lookup batch. Note that returned IndexLookupBatch instance can be used multiple times.

Specified by:

createLookupBatch in interface Index

Overrides:

createLookupBatch in class BaseIndex

Parameters:

filters - the table filters

filter - the filter index (0, 1,...)

Returns:

created batch or null if batched lookup is not supported by this index.

getSession

public Session getSession()

isExpired

public boolean isExpired()

getPlanSQL

public java.lang.String getPlanSQL()

Description copied from interface: Index

Get the message to show in a EXPLAIN statement.

Specified by:

getPlanSQL in interface Index

Overrides:

getPlanSQL in class BaseIndex

Returns:

the plan

close

public void close(Session session)

Description copied from interface: Index

Close this index.

Specified by:

close in interface Index

Parameters:

session - the session used to write data

add

public void add(Session session,
                Row row)

Description copied from interface: Index

Add a row to the index.

Specified by:

add in interface Index

Parameters:

session - the session to use

row - the row to add

remove

public void remove(Session session,
                   Row row)

Description copied from interface: Index

Remove a row from the index.

Specified by:

remove in interface Index

Parameters:

session - the session

row - the row

getCost

public double getCost(Session session,
                      int[] masks,
                      TableFilter[] filters,
                      int filter,
                      SortOrder sortOrder,
                      java.util.HashSet<Column> allColumnsSet)

Description copied from interface: Index

Estimate the cost to search for rows given the search mask. There is one element per column in the search mask. For possible search masks, see IndexCondition.

Specified by:

getCost in interface Index

Parameters:

session - the session

masks - per-column comparison bit masks, null means 'always false', see constants in IndexCondition

filters - all joined table filters

filter - the current table filter index

sortOrder - the sort order

allColumnsSet - the set of all columns

Returns:

the estimated cost

find

public Cursor find(Session session,
                   SearchRow first,
                   SearchRow last)

Description copied from interface: Index

Find a row or a list of rows and create a cursor to iterate over the result.

Specified by:

find in interface Index

Parameters:

session - the session

first - the first row, or null for no limit

last - the last row, or null for no limit

Returns:

the cursor to iterate over the results

findByGeometry

public Cursor findByGeometry(TableFilter filter,
                             SearchRow first,
                             SearchRow last,
                             SearchRow intersection)

Description copied from interface: SpatialIndex

Find a row or a list of rows and create a cursor to iterate over the result.

Specified by:

findByGeometry in interface SpatialIndex

Parameters:

filter - the table filter (which possibly knows about additional conditions)

first - the lower bound

last - the upper bound

intersection - the geometry which values should intersect with, or null for anything

Returns:

the cursor to iterate over the results

setupQueryParameters

public void setupQueryParameters(Session session,
                                 SearchRow first,
                                 SearchRow last,
                                 SearchRow intersection)

Set the query parameters.

Parameters:

session - the session

first - the lower bound

last - the upper bound

intersection - the intersection

getQuery

public Query getQuery()

remove

public void remove(Session session)

Description copied from interface: Index

Remove the index.

Specified by:

remove in interface Index

Parameters:

session - the session

truncate

public void truncate(Session session)

Description copied from interface: Index

Remove all rows from the index.

Specified by:

truncate in interface Index

Parameters:

session - the session

checkRename

public void checkRename()

Description copied from class: DbObjectBase

Check if this object can be renamed. System objects may not be renamed.

Specified by:

checkRename in interface DbObject

Specified by:

checkRename in class DbObjectBase

needRebuild

public boolean needRebuild()

Description copied from interface: Index

Check if the index needs to be rebuilt. This method is called after opening an index.

Specified by:

needRebuild in interface Index

Returns:

true if a rebuild is required.

canGetFirstOrLast

public boolean canGetFirstOrLast()

Description copied from interface: Index

Check if the index can directly look up the lowest or highest value of a column.

Specified by:

canGetFirstOrLast in interface Index

Returns:

true if it can

findFirstOrLast

public Cursor findFirstOrLast(Session session,
                              boolean first)

Description copied from interface: Index

Find the first (or last) value of this index. The cursor returned is positioned on the correct row, or on null if no row has been found.

Specified by:

findFirstOrLast in interface Index

Parameters:

session - the session

first - true if the first (lowest for ascending indexes) or last value should be returned

Returns:

a cursor (never null)

setRecursive

public void setRecursive(boolean value)

getRowCount

public long getRowCount(Session session)

Description copied from interface: Index

Get the row count of this table, for the given session.

Specified by:

getRowCount in interface Index

Parameters:

session - the session

Returns:

the row count

getRowCountApproximation

public long getRowCountApproximation()

Description copied from interface: Index

Get the approximated row count for this table.

Specified by:

getRowCountApproximation in interface Index

Returns:

the approximated row count

getDiskSpaceUsed

public long getDiskSpaceUsed()

Description copied from interface: Index

Get the used disk space for this index.

Specified by:

getDiskSpaceUsed in interface Index

Returns:

the estimated number of bytes

isRecursive

public boolean isRecursive()