Package org.apache.derby.impl.sql.execute

Class IndexChanger

  • class IndexChanger
extends java.lang.Object
    Perform Index maintenance associated with DML operations for a single index.

    • Method Detail

      • setRowHolder

        void setRowHolder​(TemporaryRowHolderImpl rowHolder)
        Set the row holder for this changer to use. If the row holder is set, it wont bother saving copies of rows needed for deferred processing. Also, it will never close the passed in rowHolder.
        Parameters:
        rowHolder - the row holder

      • setBaseCC

        void setBaseCC​(ConglomerateController baseCC)
        Propagate the heap's ConglomerateController to this index changer.
        Parameters:
        baseCC - The heap's ConglomerateController.

      • setOurIndexRow

        private void setOurIndexRow​(ExecRow baseRow,
                            RowLocation baseRowLoc)
                     throws StandardException
        Set the column values for 'ourIndexRow' to refer to a base table row and location provided by the caller. The idea here is to
        Parameters:
        baseRow - a base table row.
        baseRowLoc - baseRowLoc baseRow's location
        Throws:
        StandardException - Thrown on error

      • setOurUpdatedIndexRow

        private void setOurUpdatedIndexRow​(ExecRow baseRow,
                                   RowLocation baseRowLoc)
                            throws StandardException
        Set the column values for 'ourUpdatedIndexRow' to refer to a base table row and location provided by the caller. The idea here is to
        Parameters:
        baseRow - a base table row.
        baseRowLoc - baseRowLoc baseRow's location
        Throws:
        StandardException - Thrown on error

      • indexRowChanged

        private boolean indexRowChanged()
                         throws StandardException
        Determine whether or not any columns in the current index row are being changed by the update. No need to update the index if no columns changed.
        Returns:
        Nothing.
        Throws:
        StandardException - Thrown on error

      • setScan

        private void setScan()
              throws StandardException
        Position our index scan to 'ourIndexRow'.

        This creates the scan the first time it is called.

        Throws:
        StandardException - Thrown on error

      • doDelete

        private void doDelete()
               throws StandardException
        Delete a row from our index. This assumes our index ScanController is positioned before the row by setScan if we own the SC, otherwise it is positioned on the row by the underlying index scan.

        This verifies the row exists and is unique.

        Throws:
        StandardException - Thrown on error

      • doInsert

        private void doInsert()
               throws StandardException
        Insert a row into our indes.

        This opens our index ConglomeratController the first time it is called.

        Throws:
        StandardException - Thrown on error

      • doDeferredInsert

        private void doDeferredInsert()
                       throws StandardException
        Insert a row into the temporary conglomerate

        This opens our deferred ConglomeratController the first time it is called.

        Throws:
        StandardException - Thrown on error

      • insertAndCheckDups

        private void insertAndCheckDups​(ExecIndexRow row)
                         throws StandardException
        Insert the given row into the given conglomerate and check for duplicate key error.
        Parameters:
        row - The row to insert
        Throws:
        StandardException - Thrown on duplicate key error unless we have a deferred constraint. In that index rows are saved for checking on commit.

      • delete

        void delete​(ExecRow baseRow,
            RowLocation baseRowLocation)
     throws StandardException
        Perform index maintenance to support a delete of a base table row.
        Parameters:
        baseRow - the base table row.
        baseRowLocation - the base table row's location.
        Throws:
        StandardException - Thrown on error

      • update

        void update​(ExecRow oldBaseRow,
            ExecRow newBaseRow,
            RowLocation baseRowLocation)
     throws StandardException
        Perform index maintenance to support an update of a base table row.
        Parameters:
        oldBaseRow - the old image of the base table row.
        newBaseRow - the new image of the base table row.
        baseRowLocation - the base table row's location.
        Throws:
        StandardException - Thrown on error

      • insert

        void insert​(ExecRow newRow,
            RowLocation baseRowLocation)
     throws StandardException
        Perform index maintenance to support an insert of a base table row.
        Parameters:
        newRow - the base table row.
        baseRowLocation - the base table row's location.
        Throws:
        StandardException - Thrown on error

      • insertForUpdate

        void insertForUpdate​(ExecRow newRow,
                     RowLocation baseRowLocation)
              throws StandardException
        If we're updating a unique index, the inserts have to be deferred. This is to avoid uniqueness violations that are only temporary. If we do all the deletes first, only "true" uniqueness violations can happen. We do this here, rather than in open(), because this is the only operation that requires deferred inserts, and we only want to create the conglomerate if necessary.
        Parameters:
        newRow - the base table row.
        baseRowLocation - the base table row's location.
        Throws:
        StandardException - Thrown on error

      • finish

        void finish()
     throws StandardException
        Finish doing the changes for this index. This is intended for deferred inserts for unique indexes. It has no effect unless we are doing an update of a unique index.
        Throws:
        StandardException - Thrown on error