Package org.h2.table

Class DualTable

java.lang.Object

org.h2.engine.DbObject

org.h2.schema.SchemaObject

org.h2.table.Table

org.h2.table.VirtualTable

org.h2.table.DualTable

All Implemented Interfaces:

HasSQL

public class DualTable
extends VirtualTable

The DUAL table for selects without a FROM clause.

Field Summary

Fields

Modifier and Type	Field	Description
static java.lang.String	NAME	The name of the range table.

Fields inherited from class org.h2.table.Table

columns, compareMode, EXCLUSIVE_LOCK, isHidden, READ_LOCK, TYPE_CACHED, TYPE_MEMORY, WRITE_LOCK

Fields inherited from class org.h2.engine.DbObject

AGGREGATE, comment, COMMENT, CONSTANT, CONSTRAINT, database, DOMAIN, FUNCTION_ALIAS, INDEX, RIGHT, ROLE, SCHEMA, SEQUENCE, SETTING, SYNONYM, TABLE_OR_VIEW, trace, TRIGGER, USER

Fields inherited from interface org.h2.util.HasSQL

ADD_PLAN_INFORMATION, DEFAULT_SQL_FLAGS, NO_CASTS, QUOTE_ONLY_WHEN_REQUIRED, REPLACE_LOBS_FOR_TRACE, TRACE_SQL_FLAGS

Constructor Summary

Constructors

Constructor	Description
DualTable(Database database)	Create a new range with the given start and end expressions.

Method Summary

Modifier and Type	Method	Description
boolean	canGetRowCount(SessionLocal session)	Check if the row count can be retrieved quickly.
long	getMaxDataModificationId()	Get the last data modification id.
long	getRowCount(SessionLocal session)	Get the row count for this table.
long	getRowCountApproximation(SessionLocal session)	Get the approximated row count for this table.
Index	getScanIndex(SessionLocal session)	Get the scan index to iterate through all rows.
java.lang.StringBuilder	getSQL(java.lang.StringBuilder builder, int sqlFlags)	Appends the SQL statement of this object to the specified builder.
TableType	getTableType()	Get the table type name
boolean	isDeterministic()	Check if the table is deterministic.

Methods inherited from class org.h2.table.VirtualTable

addIndex, addRow, canDrop, canReference, checkRename, checkSupportAlter, close, getCreateSQL, getIndexes, isInsertable, removeRow, truncate

Methods inherited from class org.h2.table.Table

addConstraint, addDependencies, addDependentView, addSequence, addSynonym, addTrigger, canTruncate, checkDeadlock, checkWritingAllowed, compareValues, convertInsertRow, convertUpdateRow, createRow, doesColumnExist, dropMultipleColumnsConstraintsAndIndexes, findColumn, findPrimaryKey, fire, fireAfterRow, fireBeforeRow, fireRow, getBestPlanItem, getCheckForeignKeyConstraints, getChildren, getColumn, getColumn, getColumn, getColumns, getCompareMode, getConstraints, getCreateSQLForCopy, getDependentViews, getDiskSpaceUsed, getIdentityColumn, getIndex, getIndexForColumn, getMainIndexColumn, getNullRow, getOnCommitDrop, getOnCommitTruncate, getPrimaryKey, getRow, getRowFactory, getRowIdColumn, getScanIndex, getSQLTableType, getTemplateRow, getTemplateSimpleRow, getTriggers, getType, hasSelectTrigger, isGlobalTemporary, isHidden, isLockedExclusively, isLockedExclusivelyBy, isPersistData, isPersistIndexes, isQueryComparable, isRowLockable, isTableExpression, isView, lock, lockRow, removeChildrenAndResources, removeColumnExpressionsDependencies, removeConstraint, removeDependentView, removeIndex, removeIndexOrTransferOwnership, removeSequence, removeSynonym, removeTrigger, rename, renameColumn, setCheckForeignKeyConstraints, setColumns, setHidden, setOnCommitDrop, setOnCommitTruncate, setTableExpression, unlock, updateRow, updateRows

Methods inherited from class org.h2.schema.SchemaObject

getSchema, getSQL

Methods inherited from class org.h2.engine.DbObject

getComment, getCreateSQLForMeta, getDatabase, getDropSQL, getId, getModificationId, getName, invalidate, isTemporary, isValid, 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.util.HasSQL

getTraceSQL

Field Detail

NAME

public static final java.lang.String NAME

The name of the range table.

See Also:

Constant Field Values

Constructor Detail

DualTable

public DualTable(Database database)

Create a new range with the given start and end expressions.

Parameters:

database - the database

Method Detail

getSQL

public java.lang.StringBuilder getSQL(java.lang.StringBuilder builder,
                                      int sqlFlags)

Description copied from interface: HasSQL

Appends the SQL statement of this object to the specified builder.

Specified by:

getSQL in interface HasSQL

Overrides:

getSQL in class SchemaObject

Parameters:

builder - string builder

sqlFlags - formatting flags

Returns:

the specified string builder

canGetRowCount

public boolean canGetRowCount(SessionLocal session)

Description copied from class: Table

Check if the row count can be retrieved quickly.

Specified by:

canGetRowCount in class Table

Parameters:

session - the session

Returns:

true if it can

getRowCount

public long getRowCount(SessionLocal session)

Description copied from class: Table

Get the row count for this table.

Specified by:

getRowCount in class Table

Parameters:

session - the session

Returns:

the row count

getTableType

public TableType getTableType()

Description copied from class: Table

Get the table type name

Overrides:

getTableType in class VirtualTable

Returns:

the table type name

getScanIndex

public Index getScanIndex(SessionLocal session)

Description copied from class: Table

Get the scan index to iterate through all rows.

Specified by:

getScanIndex in class Table

Parameters:

session - the session

Returns:

the index

getMaxDataModificationId

public long getMaxDataModificationId()

Description copied from class: Table

Get the last data modification id.

Specified by:

getMaxDataModificationId in class Table

Returns:

the modification id

getRowCountApproximation

public long getRowCountApproximation(SessionLocal session)

Description copied from class: Table

Get the approximated row count for this table.

Specified by:

getRowCountApproximation in class Table

Parameters:

session - the session

Returns:

the approximated row count

isDeterministic

public boolean isDeterministic()

Description copied from class: Table

Check if the table is deterministic.

Specified by:

isDeterministic in class Table

Returns:

true if it is