Package org.h2.result

Class LocalResult

  • All Implemented Interfaces:
    java.lang.AutoCloseable, ResultInterface, ResultTarget
    public class LocalResult
extends java.lang.Object
implements ResultInterface, ResultTarget
    A local result set contains all row data of a result set. This is the object generated by engine, and it is also used directly by the ResultSet class in the embedded mode. If the result does not fit in memory, it is written to a temporary file.

    • Field Detail

      • maxMemoryRows

        private int maxMemoryRows

      • visibleColumnCount

        private int visibleColumnCount

      • resultColumnCount

        private int resultColumnCount

      • forDataChangeDeltaTable

        private boolean forDataChangeDeltaTable

      • rowId

        private long rowId

      • rowCount

        private long rowCount

      • rows

        private java.util.ArrayList<Value[]> rows

      • distinctRows

        private java.util.TreeMap<ValueRow,​Value[]> distinctRows

      • currentRow

        private Value[] currentRow

      • offset

        private long offset

      • limit

        private long limit

      • fetchPercent

        private boolean fetchPercent

      • withTiesSortOrder

        private SortOrder withTiesSortOrder

      • limitsWereApplied

        private boolean limitsWereApplied

      • distinct

        private boolean distinct

      • distinctIndexes

        private int[] distinctIndexes

      • closed

        private boolean closed

      • containsLobs

        private boolean containsLobs

      • containsNull

        private java.lang.Boolean containsNull

    • Constructor Detail

      • LocalResult

        public LocalResult()
        Construct a local result object.

      • LocalResult

        private LocalResult​(SessionLocal session)

      • LocalResult

        public LocalResult​(SessionLocal session,
                   Expression[] expressions,
                   int visibleColumnCount,
                   int resultColumnCount)
        Construct a local result object.
        Parameters:
        session - the session
        expressions - the expression array
        visibleColumnCount - the number of visible columns
        resultColumnCount - the number of columns including visible columns and additional virtual columns for ORDER BY and DISTINCT ON clauses

    • Method Detail

      • forTable

        public static LocalResult forTable​(SessionLocal session,
                                   Table table)
        Constructs a new local result object for the specified table.
        Parameters:
        session - the session
        table - the table
        Returns:
        the local result

      • isLazy

        public boolean isLazy()
        Description copied from interface: ResultInterface
        Check if this a lazy execution result.
        Specified by:
        isLazy in interface ResultInterface
        Returns:
        true if it is a lazy result

      • setMaxMemoryRows

        public void setMaxMemoryRows​(int maxValue)
        Redefine count of maximum rows holds in memory for the result.
        Parameters:
        maxValue - Maximum rows count in memory.
        See Also:
        SysProperties.MAX_MEMORY_ROWS

      • setForDataChangeDeltaTable

        public void setForDataChangeDeltaTable()
        Sets value collection mode for data change delta tables.

      • createShallowCopy

        public LocalResult createShallowCopy​(Session targetSession)
        Create a shallow copy of the result set. The data and a temporary table (if there is any) is not copied.
        Specified by:
        createShallowCopy in interface ResultInterface
        Parameters:
        targetSession - the session of the copy
        Returns:
        the copy if possible, or null if copying is not possible

      • setSortOrder

        public void setSortOrder​(SortOrder sort)
        Sets sort order to be used by this result. When rows are presorted by the query this method should not be used.
        Parameters:
        sort - the sort order

      • setDistinct

        public void setDistinct()
        Remove duplicate rows.

      • setDistinct

        public void setDistinct​(int[] distinctIndexes)
        Remove rows with duplicates in columns with specified indexes.
        Parameters:
        distinctIndexes - distinct indexes

      • isAnyDistinct

        private boolean isAnyDistinct()
        Returns:
        whether this result is a distinct result

      • containsDistinct

        public boolean containsDistinct​(Value[] values)
        Check if this result set contains the given row.
        Parameters:
        values - the row
        Returns:
        true if the row exists

      • containsNull

        public boolean containsNull()
        Check if this result set contains a NULL value. This method may reset this result.
        Returns:
        true if there is a NULL value

      • removeDistinct

        public void removeDistinct​(Value[] values)
        Remove the row from the result set if it exists.
        Parameters:
        values - the row

      • reset

        public void reset()
        Description copied from interface: ResultInterface
        Go to the beginning of the result, that means before the first row.
        Specified by:
        reset in interface ResultInterface

      • currentRowForTable

        public Row currentRowForTable()
        Retrieve the current row
        Returns:
        row

      • next

        public boolean next()
        Description copied from interface: ResultInterface
        Go to the next row.
        Specified by:
        next in interface ResultInterface
        Returns:
        true if a row exists

      • getRowId

        public long getRowId()
        Description copied from interface: ResultInterface
        Get the current row id, starting with 0. -1 is returned when next() was not called yet.
        Specified by:
        getRowId in interface ResultInterface
        Returns:
        the row id

      • isAfterLast

        public boolean isAfterLast()
        Description copied from interface: ResultInterface
        Check if the current position is after last row.
        Specified by:
        isAfterLast in interface ResultInterface
        Returns:
        true if after last

      • cloneLobs

        private void cloneLobs​(Value[] values)

      • getDistinctRow

        private ValueRow getDistinctRow​(Value[] values)

      • createExternalResult

        private void createExternalResult()

      • addRowForTable

        public void addRowForTable​(Row row)
        Add a row for a table.
        Parameters:
        row - the row to add

      • addRow

        public void addRow​(Value... values)
        Add a row to this object.
        Specified by:
        addRow in interface ResultTarget
        Parameters:
        values - the row to add

      • addRowInternal

        private void addRowInternal​(Value... values)

      • addRowsToDisk

        private void addRowsToDisk()

      • getVisibleColumnCount

        public int getVisibleColumnCount()
        Description copied from interface: ResultInterface
        Get the number of visible columns. More columns may exist internally for sorting or grouping.
        Specified by:
        getVisibleColumnCount in interface ResultInterface
        Returns:
        the number of columns

      • done

        public void done()
        This method is called after all rows have been added.

      • applyOffsetAndLimit

        private void applyOffsetAndLimit()

      • trimExternal

        private void trimExternal​(long offset,
                          long limit)

      • limitsWereApplied

        public void limitsWereApplied()
        Description copied from interface: ResultTarget
        A hint that sorting, offset and limit may be ignored by this result because they were applied during the query. This is useful for WITH TIES clause because result may contain tied rows above limit.
        Specified by:
        limitsWereApplied in interface ResultTarget

      • hasNext

        public boolean hasNext()
        Description copied from interface: ResultInterface
        Check if this result has more rows to fetch.
        Specified by:
        hasNext in interface ResultInterface
        Returns:
        true if it has

      • setLimit

        public void setLimit​(long limit)
        Set the number of rows that this result will return at the maximum.
        Parameters:
        limit - the limit (-1 means no limit, 0 means no rows)

      • setFetchPercent

        public void setFetchPercent​(boolean fetchPercent)
        Parameters:
        fetchPercent - whether limit expression specifies percentage of rows

      • setWithTies

        public void setWithTies​(SortOrder withTiesSortOrder)
        Enables inclusion of tied rows to result and sets the sort order for tied rows. The specified sort order must be the same as sort order if sort order was set. Passed value will be used if sort order was not set that is possible when rows are presorted.
        Parameters:
        withTiesSortOrder - the sort order for tied rows

      • needToClose

        public boolean needToClose()
        Description copied from interface: ResultInterface
        Check if this result set should be closed, for example because it is buffered using a temporary file.
        Specified by:
        needToClose in interface ResultInterface
        Returns:
        true if close should be called.

      • close

        public void close()
        Description copied from interface: ResultInterface
        Close the result and delete any temporary files
        Specified by:
        close in interface java.lang.AutoCloseable
        Specified by:
        close in interface ResultInterface

      • getAlias

        public java.lang.String getAlias​(int i)
        Description copied from interface: ResultInterface
        Get the column alias name for the column.
        Specified by:
        getAlias in interface ResultInterface
        Parameters:
        i - the column number (starting with 0)
        Returns:
        the alias name

      • getTableName

        public java.lang.String getTableName​(int i)
        Description copied from interface: ResultInterface
        Get the table name for the column, if one exists.
        Specified by:
        getTableName in interface ResultInterface
        Parameters:
        i - the column number (starting with 0)
        Returns:
        the table name or null

      • getSchemaName

        public java.lang.String getSchemaName​(int i)
        Description copied from interface: ResultInterface
        Get the schema name for the column, if one exists.
        Specified by:
        getSchemaName in interface ResultInterface
        Parameters:
        i - the column number (starting with 0)
        Returns:
        the schema name or null

      • getColumnName

        public java.lang.String getColumnName​(int i)
        Description copied from interface: ResultInterface
        Get the column name.
        Specified by:
        getColumnName in interface ResultInterface
        Parameters:
        i - the column number (starting with 0)
        Returns:
        the column name

      • getColumnType

        public TypeInfo getColumnType​(int i)
        Description copied from interface: ResultInterface
        Get the column data type.
        Specified by:
        getColumnType in interface ResultInterface
        Parameters:
        i - the column number (starting with 0)
        Returns:
        the column data type

      • getNullable

        public int getNullable​(int i)
        Description copied from interface: ResultInterface
        Check if this column is nullable.
        Specified by:
        getNullable in interface ResultInterface
        Parameters:
        i - the column number (starting with 0)
        Returns:
        Column.NULLABLE_*

      • isIdentity

        public boolean isIdentity​(int i)
        Description copied from interface: ResultInterface
        Check if this is an identity column.
        Specified by:
        isIdentity in interface ResultInterface
        Parameters:
        i - the column number (starting with 0)
        Returns:
        true for identity columns

      • setOffset

        public void setOffset​(long offset)
        Set the offset of the first row to return.
        Parameters:
        offset - the offset

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object

      • isClosed

        public boolean isClosed()
        Check if this result set is closed.
        Specified by:
        isClosed in interface ResultInterface
        Returns:
        true if it is

      • getFetchSize

        public int getFetchSize()
        Description copied from interface: ResultInterface
        Get the current fetch size for this result set.
        Specified by:
        getFetchSize in interface ResultInterface
        Returns:
        the fetch size

      • setFetchSize

        public void setFetchSize​(int fetchSize)
        Description copied from interface: ResultInterface
        Set the fetch size for this result set.
        Specified by:
        setFetchSize in interface ResultInterface
        Parameters:
        fetchSize - the new fetch size