Package org.h2.table

Class Table

java.lang.Object
org.h2.engine.DbObject
org.h2.schema.SchemaObject
org.h2.table.Table
All Implemented Interfaces:
HasSQL
Direct Known Subclasses:
MaterializedView, MetaTable, QueryExpressionTable, TableBase, TableLink, VirtualTable
public abstract class Table extends SchemaObject
This is the base class for most tables. A table contains a list of columns and a list of rows.

  • Field Details

    • TYPE_CACHED

      public static final int TYPE_CACHED
      The table type that means this table is a regular persistent table.
      See Also:

    • TYPE_MEMORY

      public static final int TYPE_MEMORY
      The table type that means this table is a regular persistent table.
      See Also:

    • READ_LOCK

      public static final int READ_LOCK
      Read lock.
      See Also:

    • WRITE_LOCK

      public static final int WRITE_LOCK
      Write lock.
      See Also:

    • EXCLUSIVE_LOCK

      public static final int EXCLUSIVE_LOCK
      Exclusive lock.
      See Also:

    • columns

      protected Column[] columns
      The columns of this table.

    • compareMode

      protected CompareMode compareMode
      The compare mode used for this table.

  • Constructor Details

    • Table

      protected Table(Schema schema, int id, String name, boolean persistIndexes, boolean persistData)

  • Method Details

    • rename

      public void rename(String newName)
      Description copied from class: DbObject
      Rename the object.
      Overrides:
      rename in class DbObject
      Parameters:
      newName - the new name

    • isView

      public boolean isView()

    • lock

      public boolean lock(SessionLocal session, int lockType)
      Lock the table for the given session. This method waits until the lock is granted.
      Parameters:
      session - the session
      lockType - the type of lock
      Returns:
      true if the table was already exclusively locked by this session.
      Throws:
      DbException - if a lock timeout occurred

    • close

      public abstract void close(SessionLocal session)
      Close the table object and flush changes.
      Parameters:
      session - the session

    • unlock

      public void unlock(SessionLocal s)
      Release the lock for this session.
      Parameters:
      s - the session

    • addIndex

      public abstract Index addIndex(SessionLocal session, String indexName, int indexId, IndexColumn[] cols, int uniqueColumnCount, IndexType indexType, boolean create, 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
      uniqueColumnCount - the count of unique columns
      indexType - the index type
      create - whether this is a new index
      indexComment - the comment
      Returns:
      the index

    • getRow

      public Row getRow(SessionLocal session, long key)
      Get the given row.
      Parameters:
      session - the session
      key - the primary key
      Returns:
      the row

    • isInsertable

      public boolean isInsertable()
      Returns whether this table is insertable.
      Returns:
      whether this table is insertable

    • removeRow

      public abstract void removeRow(SessionLocal session, Row row)
      Remove a row from the table and all indexes.
      Parameters:
      session - the session
      row - the row

    • lockRow

      public Row lockRow(SessionLocal session, Row row, int timeoutMillis)
      Locks row, preventing any updated to it, except from the session specified.
      Parameters:
      session - the session
      row - to lock
      timeoutMillis - timeout in milliseconds, -1 for default, -2 to skip locking if row is already locked by another session
      Returns:
      locked row, or null if row does not exist anymore or if it was skipped

    • truncate

      public abstract long truncate(SessionLocal session)
      Remove all rows from the table and indexes.
      Parameters:
      session - the session
      Returns:
      number of removed rows, possibly including uncommitted rows

    • addRow

      public abstract void addRow(SessionLocal session, Row row)
      Add a row to the table and all indexes.
      Parameters:
      session - the session
      row - the row
      Throws:
      DbException - if a constraint was violated

    • updateRow

      public void updateRow(SessionLocal session, Row oldRow, Row newRow)
      Update a row to the table and all indexes.
      Parameters:
      session - the session
      oldRow - the row to update
      newRow - the row with updated values (_rowid_ suppose to be the same)
      Throws:
      DbException - if a constraint was violated

    • checkSupportAlter

      public abstract void checkSupportAlter()
      Check if this table supports ALTER TABLE.
      Throws:
      DbException - if it is not supported

    • getTableType

      public abstract TableType getTableType()
      Get the table type name
      Returns:
      the table type name

    • getSQLTableType

      public String getSQLTableType()
      Return SQL table type for INFORMATION_SCHEMA.
      Returns:
      SQL table type for INFORMATION_SCHEMA

    • getScanIndex

      public abstract Index getScanIndex(SessionLocal session)
      Get the scan index to iterate through all rows.
      Parameters:
      session - the session
      Returns:
      the index

    • getScanIndex

      public Index getScanIndex(SessionLocal session, int[] masks, TableFilter[] filters, int filter, SortOrder sortOrder, AllColumnsForPlan allColumnsSet)
      Get the scan index for this table.
      Parameters:
      session - the session
      masks - the search mask
      filters - the table filters
      filter - the filter index
      sortOrder - the sort order
      allColumnsSet - all columns
      Returns:
      the scan index

    • getIndexes

      public abstract ArrayList<Index> getIndexes()
      Get all indexes for this table.
      Returns:
      the list of indexes

    • getIndex

      public Index getIndex(String indexName)
      Get an index by name.
      Parameters:
      indexName - the index name to search for
      Returns:
      the found index

    • isLockedExclusively

      public 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(SessionLocal session)
      Check if the row count can be retrieved quickly.
      Parameters:
      session - the session
      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

    • getRowCount

      public abstract long getRowCount(SessionLocal session)
      Get the row count for this table.
      Parameters:
      session - the session
      Returns:
      the row count

    • getRowCountApproximation

      public abstract long getRowCountApproximation(SessionLocal session)
      Get the approximated row count for this table.
      Parameters:
      session - the session
      Returns:
      the approximated row count

    • getDiskSpaceUsed

      public long getDiskSpaceUsed(boolean total, boolean approximate)

    • getRowIdColumn

      public Column getRowIdColumn()
      Get the row id column if this table has one.
      Returns:
      the row id column, or null

    • isQueryComparable

      public boolean isQueryComparable()
      Check whether the table (or view) contains no columns that prevent index conditions to be used. For example, a view that contains the ROWNUM() pseudo-column prevents this.
      Returns:
      true if the table contains no query-comparable column

    • addDependencies

      public void addDependencies(HashSet<DbObject> dependencies)
      Add all objects that this table depends on to the hash set.
      Parameters:
      dependencies - the current set of dependencies

    • getChildren

      public ArrayList<DbObject> getChildren()
      Description copied from class: DbObject
      Get the list of dependent children (for tables, this includes indexes and so on).
      Overrides:
      getChildren in class DbObject
      Returns:
      the list of children, or null

    • setColumns

      protected void setColumns(Column[] columns)

    • renameColumn

      public void renameColumn(Column column, String newName)
      Rename a column of this table.
      Parameters:
      column - the column to rename
      newName - the new column name

    • isLockedExclusivelyBy

      public boolean isLockedExclusivelyBy(SessionLocal 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, SessionLocal session, LocalResult 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,...

    • getDependentViews

      public CopyOnWriteArrayList<TableView> getDependentViews()

    • getDependentMaterializedViews

      public CopyOnWriteArrayList<MaterializedView> getDependentMaterializedViews()

    • removeChildrenAndResources

      public void removeChildrenAndResources(SessionLocal session)
      Description copied from class: DbObject
      Delete all dependent children objects and resources of this object.
      Specified by:
      removeChildrenAndResources in class DbObject
      Parameters:
      session - the session

    • dropMultipleColumnsConstraintsAndIndexes

      public void dropMultipleColumnsConstraintsAndIndexes(SessionLocal session, ArrayList<Column> columnsToDrop)
      Check that these columns are 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
      columnsToDrop - the columns to drop
      Throws:
      DbException - if the column is referenced by multi-column constraints or indexes

    • getRowFactory

      public RowFactory getRowFactory()

    • createRow

      public Row createRow(Value[] data, int memory)
      Create a new row for this table.
      Parameters:
      data - the values
      memory - the estimated memory usage in bytes
      Returns:
      the created row

    • 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

    • getNullRow

      public Row getNullRow()

    • getColumns

      public final Column[] getColumns()

    • getVisibleColumns

      public final Column[] getVisibleColumns()

    • getType

      public int getType()
      Description copied from class: DbObject
      Get the object type.
      Specified by:
      getType in class DbObject
      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(String columnName)
      Get the column with the given name.
      Parameters:
      columnName - the column name
      Returns:
      the column
      Throws:
      DbException - if the column was not found

    • getColumn

      public Column getColumn(String columnName, boolean ifExists)
      Get the column with the given name.
      Parameters:
      columnName - the column name
      ifExists - if true return null if column does not exist
      Returns:
      the column
      Throws:
      DbException - if the column was not found

    • findColumn

      public Column findColumn(String columnName)
      Get the column with the given name if it exists.
      Parameters:
      columnName - the column name, or null
      Returns:
      the column

    • doesColumnExist

      public boolean doesColumnExist(String columnName)
      Does the column with the given name exist?
      Parameters:
      columnName - the column name
      Returns:
      true if the column exists

    • getIdentityColumn

      public Column getIdentityColumn()
      Returns first identity column, or null.
      Returns:
      first identity column, or null

    • getBestPlanItem

      public PlanItem getBestPlanItem(SessionLocal session, int[] masks, TableFilter[] filters, int filter, SortOrder sortOrder, AllColumnsForPlan allColumnsSet)
      Get the best plan for the given search mask.
      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 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()

    • convertInsertRow

      public void convertInsertRow(SessionLocal session, Row row, Boolean overridingSystem)
      Prepares the specified row for INSERT operation. Identity, default, and generated values are evaluated, all values are converted to target data types and validated. Base value of identity column is updated when required by compatibility mode.
      Parameters:
      session - the session
      overridingSystem - Boolean.TRUE for OVERRIDING SYSTEM VALUES, Boolean.FALSE for OVERRIDING USER VALUES, null if override clause is not specified
      row - the row

    • convertUpdateRow

      public void convertUpdateRow(SessionLocal session, Row row, boolean fromTrigger)
      Prepares the specified row for UPDATE operation. Default and generated values are evaluated, all values are converted to target data types and validated. Base value of identity column is updated when required by compatibility mode.
      Parameters:
      session - the session
      row - the row
      fromTrigger - true if row was modified by INSERT or UPDATE trigger

    • removeIndex

      public void removeIndex(Index index)
      Remove the given index from the list.
      Parameters:
      index - the index to remove

    • removeDependentView

      public void removeDependentView(TableView view)
      Remove the given view from the dependent views list.
      Parameters:
      view - the view to remove

    • removeDependentMaterializedView

      public void removeDependentMaterializedView(MaterializedView view)
      Remove the given view from the dependent views list.
      Parameters:
      view - the view to remove

    • removeSynonym

      public void removeSynonym(TableSynonym synonym)
      Remove the given view from the list.
      Parameters:
      synonym - the synonym to remove

    • removeConstraint

      public void removeConstraint(Constraint constraint)
      Remove the given constraint from the list.
      Parameters:
      constraint - the constraint to remove

    • removeSequence

      public final void removeSequence(Sequence sequence)
      Remove a sequence from the table. Sequences are used as identity columns.
      Parameters:
      sequence - the sequence to remove

    • removeTrigger

      public void removeTrigger(TriggerObject trigger)
      Remove the given trigger from the list.
      Parameters:
      trigger - the trigger to remove

    • addDependentView

      public void addDependentView(TableView view)
      Add a view to this table.
      Parameters:
      view - the view to add

    • addDependentMaterializedView

      public void addDependentMaterializedView(MaterializedView view)
      Add a materialized view to this table.
      Parameters:
      view - the view to add

    • addSynonym

      public void addSynonym(TableSynonym synonym)
      Add a synonym to this table.
      Parameters:
      synonym - the synonym to add

    • addConstraint

      public void addConstraint(Constraint constraint)
      Add a constraint to the table.
      Parameters:
      constraint - the constraint to add

    • getConstraints

      public 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(SessionLocal 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(SessionLocal 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(SessionLocal 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(SessionLocal 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()
      Returns:
      is foreign key constraint checking enabled for this table.

    • getIndexForColumn

      public Index getIndexForColumn(Column column, boolean needGetFirstOrLast, boolean needFindNext)
      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
      needGetFirstOrLast - if the returned index must be able to do Index.canGetFirstOrLast()
      needFindNext - if the returned index must be able to do Index.findNext(SessionLocal, SearchRow, SearchRow)
      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(SessionLocal 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

    • removeColumnExpressionsDependencies

      public void removeColumnExpressionsDependencies(SessionLocal session)
      Removes dependencies of column expressions, used for tables with circular dependencies.
      Parameters:
      session - the session

    • checkDeadlock

      public ArrayList<SessionLocal> checkDeadlock(SessionLocal session, SessionLocal clash, Set<SessionLocal> 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()

    • compareValues

      public int compareValues(CastDataProvider provider, Value a, Value b)
      Compare two values with the current comparison mode. The values may be of different type.
      Parameters:
      provider - the cast information provider
      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.

    • isRowLockable

      public boolean isRowLockable()
      Views, function tables, links, etc. do not support locks
      Returns:
      true if table supports row-level locks

    • getTriggers

      public ArrayList<TriggerObject> getTriggers()
      Return list of triggers.
      Returns:
      list of triggers

    • getMainIndexColumn

      public int getMainIndexColumn()
      Returns ID of main index column, or SearchRow.ROWID_INDEX.
      Returns:
      ID of main index column, or SearchRow.ROWID_INDEX