Package org.h2.index

Class MetaIndex

  • All Implemented Interfaces:
    HasSQL

    public class MetaIndex
    extends Index
    The index implementation for meta data tables.
    • Field Detail

      • scan

        private final boolean scan
    • Method Detail

      • close

        public void close​(SessionLocal session)
        Description copied from class: Index
        Close this index.
        Specified by:
        close in class Index
        Parameters:
        session - the session used to write data
      • add

        public void add​(SessionLocal session,
                        Row row)
        Description copied from class: Index
        Add a row to the index.
        Specified by:
        add in class Index
        Parameters:
        session - the session to use
        row - the row to add
      • remove

        public void remove​(SessionLocal session,
                           Row row)
        Description copied from class: Index
        Remove a row from the index.
        Specified by:
        remove in class Index
        Parameters:
        session - the session
        row - the row
      • find

        public Cursor find​(SessionLocal session,
                           SearchRow first,
                           SearchRow last)
        Description copied from class: Index
        Find a row or a list of rows and create a cursor to iterate over the result.
        Specified by:
        find in class 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
      • getCost

        public double getCost​(SessionLocal session,
                              int[] masks,
                              TableFilter[] filters,
                              int filter,
                              SortOrder sortOrder,
                              AllColumnsForPlan allColumnsSet)
        Description copied from class: 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 class 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
      • truncate

        public void truncate​(SessionLocal session)
        Description copied from class: Index
        Remove all rows from the index.
        Specified by:
        truncate in class Index
        Parameters:
        session - the session
      • remove

        public void remove​(SessionLocal session)
        Description copied from class: Index
        Remove the index.
        Specified by:
        remove in class Index
        Parameters:
        session - the session
      • getColumnIndex

        public int getColumnIndex​(Column col)
        Description copied from class: Index
        Get the index of a column in the list of index columns
        Overrides:
        getColumnIndex in class Index
        Parameters:
        col - the column
        Returns:
        the index (0 meaning first column)
      • isFirstColumn

        public boolean isFirstColumn​(Column column)
        Description copied from class: Index
        Check if the given column is the first for this index
        Overrides:
        isFirstColumn in class Index
        Parameters:
        column - the column
        Returns:
        true if the given columns is the first
      • checkRename

        public void checkRename()
        Description copied from class: DbObject
        Check if renaming is allowed. Does nothing when allowed.
        Overrides:
        checkRename in class DbObject
      • needRebuild

        public boolean needRebuild()
        Description copied from class: Index
        Check if the index needs to be rebuilt. This method is called after opening an index.
        Specified by:
        needRebuild in class Index
        Returns:
        true if a rebuild is required.
      • getCreateSQL

        public java.lang.String getCreateSQL()
        Description copied from class: DbObject
        Construct the CREATE ... SQL statement for this object.
        Overrides:
        getCreateSQL in class Index
        Returns:
        the SQL statement
      • getRowCount

        public long getRowCount​(SessionLocal session)
        Description copied from class: Index
        Get the row count of this table, for the given session.
        Specified by:
        getRowCount in class Index
        Parameters:
        session - the session
        Returns:
        the row count
      • getRowCountApproximation

        public long getRowCountApproximation​(SessionLocal session)
        Description copied from class: Index
        Get the approximated row count for this table.
        Specified by:
        getRowCountApproximation in class Index
        Parameters:
        session - the session
        Returns:
        the approximated row count
      • getDiskSpaceUsed

        public long getDiskSpaceUsed()
        Description copied from class: Index
        Get the used disk space for this index.
        Overrides:
        getDiskSpaceUsed in class Index
        Returns:
        the estimated number of bytes
      • getPlanSQL

        public java.lang.String getPlanSQL()
        Description copied from class: Index
        Get the message to show in a EXPLAIN statement.
        Overrides:
        getPlanSQL in class Index
        Returns:
        the plan