org.h2.table
Class Table

java.lang.Object
  org.h2.engine.DbObjectBase
      org.h2.schema.SchemaObjectBase
          org.h2.table.Table

All Implemented Interfaces:

DbObject, SchemaObject

Direct Known Subclasses:

FunctionTable, MetaTable, RangeTable, TableBase, TableLink, TableView

public abstract class Table
extends SchemaObjectBase

This is the base class for most tables. A table contains a list of columns and a list of rows.

Field Summary

protected Column[]	columns The columns of this table.
protected CompareMode	compareMode The compare mode used for this table.
static java.lang.String	EXTERNAL_TABLE_ENGINE The table type name for external table engines.
protected boolean	isHidden Protected tables are not listed in the meta data and are excluded when using the SCRIPT command.
static java.lang.String	SYSTEM_TABLE The table type name for system tables.
static java.lang.String	TABLE The table type name for regular data tables.
static java.lang.String	TABLE_LINK The table type name for linked tables.
static int	TYPE_CACHED The table type that means this table is a regular persistent table.
static int	TYPE_MEMORY The table type that means this table is a regular persistent table.
static java.lang.String	VIEW The table type name for views.

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, TABLE_OR_VIEW, TRIGGER, USER, USER_DATATYPE

Constructor Summary

Table(Schema schema, int id, java.lang.String name, boolean persistIndexes, boolean persistData)

Method Summary

void	addConstraint(Constraint constraint) Add a constraint to the table.
void	addDependencies(java.util.HashSet<DbObject> dependencies) Add all objects that this table depends on to the hash set.
abstract Index	addIndex(Session session, java.lang.String indexName, int indexId, IndexColumn[] cols, IndexType indexType, boolean create, java.lang.String indexComment) Create an index for this table
abstract void	addRow(Session session, Row row) Add a row to the table and all indexes.
void	addSequence(Sequence sequence) Add a sequence to this table.
void	addTrigger(TriggerObject trigger) Add a trigger to this table.
void	addView(TableView view) Add a view to this table.
abstract boolean	canDrop() Check if this table can be dropped.
abstract boolean	canGetRowCount() Check if the row count can be retrieved quickly.
boolean	canReference() Check if this table can be referenced.
boolean	canTruncate() Check if this table can be truncated.
java.util.ArrayList<Session>	checkDeadlock(Session session, Session clash, java.util.Set<Session> visited) Check if a deadlock occurred.
abstract void	checkSupportAlter() Check if this table supports ALTER TABLE.
void	checkWritingAllowed() Tests if the table can be written.
abstract void	close(Session session) Close the table object and flush changes.
void	commit(short operation, Row row) Commit an operation (when using multi-version concurrency).
int	compareTypeSave(Value a, Value b) Compare two values with the current comparison mode.
void	dropSingleColumnConstraintsAndIndexes(Session session, Column col) Check that this column is not referenced by a multi-column constraint or multi-column index.
Index	findPrimaryKey() Get the primary key index if there is one, or null if there is none.
void	fire(Session session, int type, boolean beforeAction) Fire the triggers for this table.
void	fireAfterRow(Session session, Row oldRow, Row newRow, boolean rollback) Fire all triggers that need to be called after a row is updated.
boolean	fireBeforeRow(Session session, Row oldRow, Row newRow) Fire all triggers that need to be called before a row is updated.
boolean	fireRow() Check if row based triggers or constraints are defined.
PlanItem	getBestPlanItem(Session session, int[] masks) Get the best plan for the given search mask.
boolean	getCheckForeignKeyConstraints()
java.util.ArrayList<DbObject>	getChildren() Get the list of dependent children (for tables, this includes indexes and so on).
Column	getColumn(int index) Get the column at the given index.
Column	getColumn(java.lang.String columnName) Get the column with the given name.
Column[]	getColumns()
CompareMode	getCompareMode()
java.util.ArrayList<Constraint>	getConstraints()
java.lang.String	getCreateSQLForCopy(Table table, java.lang.String quotedName) Build a SQL statement to re-create the object, or to create a copy of the object with a different name or referencing a different table
Value	getDefaultValue(Session session, Column column) Get or generate a default value for the given column.
abstract java.util.ArrayList<Index>	getIndexes() Get all indexes for this table.
Index	getIndexForColumn(Column column, boolean first) Get the index that has the given column as the first element.
abstract long	getMaxDataModificationId() Get the last data modification id.
boolean	getOnCommitDrop()
boolean	getOnCommitTruncate()
Index	getPrimaryKey()
abstract long	getRowCount(Session session) Get the row count for this table.
abstract long	getRowCountApproximation() Get the approximated row count for this table.
abstract Index	getScanIndex(Session session) Get the scan index to iterate through all rows.
abstract java.lang.String	getTableType() Get the table type name
Row	getTemplateRow()
SearchRow	getTemplateSimpleRow(boolean singleColumn) Get a new simple row object.
int	getType() Get the object type.
abstract Index	getUniqueIndex() Get any unique index for this table if one exists.
java.util.ArrayList<TableView>	getViews()
abstract boolean	hasRowIdColumn() Check if this table has a row id column.
boolean	hasSelectTrigger() Check whether this table has a select trigger.
abstract boolean	isDeterministic() Check if the table is deterministic.
boolean	isGlobalTemporary()
boolean	isHidden() Check whether this is a hidden object that doesn't appear in the meta data and in the script, and is not dropped on DROP ALL OBJECTS.
abstract boolean	isLockedExclusively() Check if this table is locked exclusively.
boolean	isLockedExclusivelyBy(Session session) Check if the table is exclusively locked by this session.
boolean	isPersistData()
boolean	isPersistIndexes()
abstract void	lock(Session session, boolean exclusive, boolean force) Lock the table for the given session.
void	removeChildrenAndResources(Session session) Remove all dependent objects and free all resources (files, blocks in files) of this object.
void	removeConstraint(Constraint constraint) Remove the given constraint from the list.
void	removeIndex(Index index) Remove the given index from the list.
void	removeIndexOrTransferOwnership(Session session, Index index) If the index is still required by a constraint, transfer the ownership to it.
abstract void	removeRow(Session session, Row row) Remove a row from the table and all indexes.
void	removeSequence(Session session, Sequence sequence) Remove a sequence from the table.
void	removeTrigger(TriggerObject trigger) Remove the given trigger from the list.
void	rename(java.lang.String newName) Rename the object.
void	renameColumn(Column column, java.lang.String newName) Rename a column of this table.
void	setCheckForeignKeyConstraints(Session session, boolean enabled, boolean checkExisting) Enable or disable foreign key constraint checking for this table.
protected void	setColumns(Column[] columns)
void	setOnCommitDrop(boolean onCommitDrop)
void	setOnCommitTruncate(boolean onCommitTruncate)
abstract void	truncate(Session session) Remove all rows from the table and indexes.
abstract void	unlock(Session s) Release the lock for this session.
void	updateRows(Prepared prepared, Session session, RowList rows) Update a list of rows in this table.
void	validateConvertUpdateSequence(Session session, Row row) Validate all values in this row, convert the values if required, and update the sequence values if required.

Methods inherited from class org.h2.schema.SchemaObjectBase

getSchema, getSQL, initSchemaObjectBase

Methods inherited from class org.h2.engine.DbObjectBase

checkRename, getComment, getCreateSQL, getDatabase, getDropSQL, getId, getModificationId, getName, initDbObjectBase, invalidate, isTemporary, 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.engine.DbObject

checkRename, getComment, getCreateSQL, getDatabase, getDropSQL, getId, getModificationId, getName, isTemporary, setComment, setModified, setTemporary

Field Detail

TYPE_CACHED

public static final int TYPE_CACHED

The table type that means this table is a regular persistent table.

See Also:

Constant Field Values

TYPE_MEMORY

public static final int TYPE_MEMORY

The table type that means this table is a regular persistent table.

See Also:

Constant Field Values

TABLE_LINK

public static final java.lang.String TABLE_LINK

The table type name for linked tables.

See Also:

Constant Field Values

SYSTEM_TABLE

public static final java.lang.String SYSTEM_TABLE

The table type name for system tables.

See Also:

Constant Field Values

TABLE

public static final java.lang.String TABLE

The table type name for regular data tables.

See Also:

Constant Field Values

VIEW

public static final java.lang.String VIEW

The table type name for views.

See Also:

Constant Field Values

EXTERNAL_TABLE_ENGINE

public static final java.lang.String EXTERNAL_TABLE_ENGINE

The table type name for external table engines.

See Also:

Constant Field Values

columns

protected Column[] columns

The columns of this table.

compareMode

protected CompareMode compareMode

The compare mode used for this table.

isHidden

protected boolean isHidden

Protected tables are not listed in the meta data and are excluded when using the SCRIPT command.

Constructor Detail

Table

public Table(Schema schema,
             int id,
             java.lang.String name,
             boolean persistIndexes,
             boolean persistData)

Method Detail

rename

public void rename(java.lang.String newName)

Description copied from interface: DbObject

Rename the object.

Specified by:

rename in interface DbObject

Overrides:

rename in class DbObjectBase

Parameters:

newName - the new name

lock

public abstract void lock(Session session,
                          boolean exclusive,
                          boolean force)

Lock the table for the given session. This method waits until the lock is granted.

Parameters:

session - the session

exclusive - true for write locks, false for read locks

force - lock even in the MVCC mode

Throws:

SQLException - if a lock timeout occurred

close

public abstract void close(Session session)

Close the table object and flush changes.

Parameters:

session - the session

unlock

public abstract void unlock(Session s)

Release the lock for this session.

Parameters:

s - the session

addIndex

public abstract Index addIndex(Session session,
                               java.lang.String indexName,
                               int indexId,
                               IndexColumn[] cols,
                               IndexType indexType,
                               boolean create,
                               java.lang.String indexComment)

Create an index for this table

Parameters:

session - the session

indexName - the name of the index

indexId - the id

cols - the index columns

indexType - the index type

create - whether this is a new index

indexComment - the comment

Returns:

the index

removeRow

public abstract void removeRow(Session session,
                               Row row)

Remove a row from the table and all indexes.

Parameters:

session - the session

row - the row

truncate

public abstract void truncate(Session session)

Remove all rows from the table and indexes.

Parameters:

session - the session

addRow

public abstract void addRow(Session session,
                            Row row)

Add a row to the table and all indexes.

Parameters:

session - the session

row - the row

Throws:

SQLException - if a constraint was violated

commit

public void commit(short operation,
                   Row row)

Commit an operation (when using multi-version concurrency).

Parameters:

operation - the operation

row - the row

checkSupportAlter

public abstract void checkSupportAlter()

Check if this table supports ALTER TABLE.

Throws:

SQLException - if it is not supported

getTableType

public abstract java.lang.String getTableType()

Get the table type name

Returns:

the table type name

getScanIndex

public abstract Index getScanIndex(Session session)

Get the scan index to iterate through all rows.

Parameters:

session - the session

Returns:

the index

getUniqueIndex

public abstract Index getUniqueIndex()

Get any unique index for this table if one exists.

Returns:

a unique index

getIndexes

public abstract java.util.ArrayList<Index> getIndexes()

Get all indexes for this table.

Returns:

the list of indexes

isLockedExclusively

public abstract boolean isLockedExclusively()

Check if this table is locked exclusively.

Returns:

true if it is.

getMaxDataModificationId

public abstract long getMaxDataModificationId()

Get the last data modification id.

Returns:

the modification id

isDeterministic

public abstract boolean isDeterministic()

Check if the table is deterministic.

Returns:

true if it is

canGetRowCount

public abstract boolean canGetRowCount()

Check if the row count can be retrieved quickly.

Returns:

true if it can

canReference

public boolean canReference()

Check if this table can be referenced.

Returns:

true if it can

canDrop

public abstract boolean canDrop()

Check if this table can be dropped.

Returns:

true if it can

hasRowIdColumn

public abstract boolean hasRowIdColumn()

Check if this table has a row id column.

Returns:

true if it has

getRowCount

public abstract long getRowCount(Session session)

Get the row count for this table.

Parameters:

session - the session

Returns:

the row count

getRowCountApproximation

public abstract long getRowCountApproximation()

Get the approximated row count for this table.

Returns:

the approximated row count

getCreateSQLForCopy

public java.lang.String getCreateSQLForCopy(Table table,
                                            java.lang.String quotedName)

Description copied from class: DbObjectBase

Build a SQL statement to re-create the object, or to create a copy of the object with a different name or referencing a different table

Specified by:

getCreateSQLForCopy in interface DbObject

Specified by:

getCreateSQLForCopy in class DbObjectBase

Parameters:

table - the new table name

quotedName - the new quoted name

Returns:

the SQL statement

addDependencies

public void addDependencies(java.util.HashSet<DbObject> dependencies)

Add all objects that this table depends on to the hash set.

Parameters:

dependencies - the current set of dependencies

getChildren

public java.util.ArrayList<DbObject> getChildren()

Description copied from interface: DbObject

Get the list of dependent children (for tables, this includes indexes and so on).

Specified by:

getChildren in interface DbObject

Overrides:

getChildren in class DbObjectBase

Returns:

the list of children

setColumns

protected void setColumns(Column[] columns)

renameColumn

public void renameColumn(Column column,
                         java.lang.String newName)

Rename a column of this table.

Parameters:

column - the column to rename

newName - the new column name

isLockedExclusivelyBy

public boolean isLockedExclusivelyBy(Session session)

Check if the table is exclusively locked by this session.

Parameters:

session - the session

Returns:

true if it is

updateRows

public void updateRows(Prepared prepared,
                       Session session,
                       RowList rows)

Update a list of rows in this table.

Parameters:

prepared - the prepared statement

session - the session

rows - a list of row pairs of the form old row, new row, old row, new row,...

getViews

public java.util.ArrayList<TableView> getViews()

removeChildrenAndResources

public void removeChildrenAndResources(Session session)

Description copied from class: DbObjectBase

Remove all dependent objects and free all resources (files, blocks in files) of this object.

Specified by:

removeChildrenAndResources in interface DbObject

Specified by:

removeChildrenAndResources in class DbObjectBase

Parameters:

session - the session

dropSingleColumnConstraintsAndIndexes

public void dropSingleColumnConstraintsAndIndexes(Session session,
                                                  Column col)

Check that this column is not referenced by a multi-column constraint or multi-column index. If it is, an exception is thrown. Single-column references and indexes are dropped.

Parameters:

session - the session

col - the column

Throws:

SQLException - if the column is referenced by multi-column constraints or indexes

getTemplateRow

public Row getTemplateRow()

getTemplateSimpleRow

public SearchRow getTemplateSimpleRow(boolean singleColumn)

Get a new simple row object.

Parameters:

singleColumn - if only one value need to be stored

Returns:

the simple row object

getColumns

public Column[] getColumns()

getType

public int getType()

Description copied from class: DbObjectBase

Get the object type.

Specified by:

getType in interface DbObject

Specified by:

getType in class DbObjectBase

Returns:

the object type

getColumn

public Column getColumn(int index)

Get the column at the given index.

Parameters:

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

Returns:

the column

getColumn

public Column getColumn(java.lang.String columnName)

Get the column with the given name.

Parameters:

columnName - the column name

Returns:

the column

Throws:

SQLException - if the column was not found

getBestPlanItem

public PlanItem getBestPlanItem(Session session,
                                int[] masks)

Get the best plan for the given search mask.

Parameters:

session - the session

masks - null means 'always false'

Returns:

the plan item

findPrimaryKey

public Index findPrimaryKey()

Get the primary key index if there is one, or null if there is none.

Returns:

the primary key index or null

getPrimaryKey

public Index getPrimaryKey()

validateConvertUpdateSequence

public void validateConvertUpdateSequence(Session session,
                                          Row row)

Validate all values in this row, convert the values if required, and update the sequence values if required. This call will also set the default values if required and set the computed column if there are any.

Parameters:

session - the session

row - the row

removeIndex

public void removeIndex(Index index)

Remove the given index from the list.

Parameters:

index - the index to remove

removeConstraint

public void removeConstraint(Constraint constraint)

Remove the given constraint from the list.

Parameters:

constraint - the constraint to remove

removeSequence

public void removeSequence(Session session,
                           Sequence sequence)

Remove a sequence from the table. Sequences are used as identity columns.

Parameters:

session - the session

sequence - the sequence to remove

removeTrigger

public void removeTrigger(TriggerObject trigger)

Remove the given trigger from the list.

Parameters:

trigger - the trigger to remove

addView

public void addView(TableView view)

Add a view to this table.

Parameters:

view - the view to add

addConstraint

public void addConstraint(Constraint constraint)

Add a constraint to the table.

Parameters:

constraint - the constraint to add

getConstraints

public java.util.ArrayList<Constraint> getConstraints()

addSequence

public void addSequence(Sequence sequence)

Add a sequence to this table.

Parameters:

sequence - the sequence to add

addTrigger

public void addTrigger(TriggerObject trigger)

Add a trigger to this table.

Parameters:

trigger - the trigger to add

fire

public void fire(Session session,
                 int type,
                 boolean beforeAction)

Fire the triggers for this table.

Parameters:

session - the session

type - the trigger type

beforeAction - whether 'before' triggers should be called

hasSelectTrigger

public boolean hasSelectTrigger()

Check whether this table has a select trigger.

Returns:

true if it has

fireRow

public boolean fireRow()

Check if row based triggers or constraints are defined. In this case the fire after and before row methods need to be called.

Returns:

if there are any triggers or rows defined

fireBeforeRow

public boolean fireBeforeRow(Session session,
                             Row oldRow,
                             Row newRow)

Fire all triggers that need to be called before a row is updated.

Parameters:

session - the session

oldRow - the old data or null for an insert

newRow - the new data or null for a delete

Returns:

true if no further action is required (for 'instead of' triggers)

fireAfterRow

public void fireAfterRow(Session session,
                         Row oldRow,
                         Row newRow,
                         boolean rollback)

Fire all triggers that need to be called after a row is updated.

Parameters:

session - the session

oldRow - the old data or null for an insert

newRow - the new data or null for a delete

rollback - when the operation occurred within a rollback

isGlobalTemporary

public boolean isGlobalTemporary()

canTruncate

public boolean canTruncate()

Check if this table can be truncated.

Returns:

true if it can

setCheckForeignKeyConstraints

public void setCheckForeignKeyConstraints(Session session,
                                          boolean enabled,
                                          boolean checkExisting)

Enable or disable foreign key constraint checking for this table.

Parameters:

session - the session

enabled - true if checking should be enabled

checkExisting - true if existing rows must be checked during this call

getCheckForeignKeyConstraints

public boolean getCheckForeignKeyConstraints()

getIndexForColumn

public Index getIndexForColumn(Column column,
                               boolean first)

Get the index that has the given column as the first element. This method returns null if no matching index is found.

Parameters:

column - the column

first - if the min value should be returned

Returns:

the index or null

getOnCommitDrop

public boolean getOnCommitDrop()

setOnCommitDrop

public void setOnCommitDrop(boolean onCommitDrop)

getOnCommitTruncate

public boolean getOnCommitTruncate()

setOnCommitTruncate

public void setOnCommitTruncate(boolean onCommitTruncate)

removeIndexOrTransferOwnership

public void removeIndexOrTransferOwnership(Session session,
                                           Index index)

If the index is still required by a constraint, transfer the ownership to it. Otherwise, the index is removed.

Parameters:

session - the session

index - the index that is no longer required

checkDeadlock

public java.util.ArrayList<Session> checkDeadlock(Session session,
                                                  Session clash,
                                                  java.util.Set<Session> visited)

Check if a deadlock occurred. This method is called recursively. There is a circle if the session to be tested has already being visited. If this session is part of the circle (if it is the clash session), the method must return an empty object array. Once a deadlock has been detected, the methods must add the session to the list. If this session is not part of the circle, or if no deadlock is detected, this method returns null.

Parameters:

session - the session to be tested for

clash - set with sessions already visited, and null when starting verification

visited - set with sessions already visited, and null when starting verification

Returns:

an object array with the sessions involved in the deadlock, or null

isPersistIndexes

public boolean isPersistIndexes()

isPersistData

public boolean isPersistData()

compareTypeSave

public int compareTypeSave(Value a,
                           Value b)

Compare two values with the current comparison mode. The values may be of different type.

Parameters:

a - the first value

b - the second value

Returns:

0 if both values are equal, -1 if the first value is smaller, and 1 otherwise

getCompareMode

public CompareMode getCompareMode()

checkWritingAllowed

public void checkWritingAllowed()

Tests if the table can be written. Usually, this depends on the database.checkWritingAllowed method, but some tables (eg. TableLink) overwrite this default behaviour.

getDefaultValue

public Value getDefaultValue(Session session,
                             Column column)

Get or generate a default value for the given column.

Parameters:

session - the session

column - the column

Returns:

the value

isHidden

public boolean isHidden()

Description copied from interface: SchemaObject

Check whether this is a hidden object that doesn't appear in the meta data and in the script, and is not dropped on DROP ALL OBJECTS.

Specified by:

isHidden in interface SchemaObject

Overrides:

isHidden in class SchemaObjectBase

Returns:

true if it is hidden