Package org.h2.result

Class LazyResult

All Implemented Interfaces:
AutoCloseable, ResultInterface
Direct Known Subclasses:
Select.LazyResultSelect, SelectUnion.LazyResultUnion

public abstract class LazyResult extends FetchedResult
Lazy execution support for queries.
  • Field Details

    • session

      private final SessionLocal session
    • expressions

      private final Expression[] expressions
    • closed

      private boolean closed
    • limit

      private long limit
  • Constructor Details

  • Method Details

    • setLimit

      public void setLimit(long limit)
    • isLazy

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

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

      public boolean skip()
      Go to the next row and skip it.
      Returns:
      true if a row exists
    • hasNext

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

      protected abstract Value[] fetchNextRow()
      Fetch next row or null if none available.
      Returns:
      next row or null
    • skipNextRow

      protected boolean skipNextRow()
      Skip next row.
      Returns:
      true if next row was available
    • getRowCount

      public long getRowCount()
      Description copied from interface: ResultInterface
      Get the number of rows in this object.
      Returns:
      the number of rows
    • isClosed

      public boolean isClosed()
      Description copied from interface: ResultInterface
      Check if this result set is closed.
      Returns:
      true if it is
    • close

      public void close()
      Description copied from interface: ResultInterface
      Close the result and delete any temporary files
    • getAlias

      public String getAlias(int i)
      Description copied from interface: ResultInterface
      Get the column alias name for the column.
      Parameters:
      i - the column number (starting with 0)
      Returns:
      the alias name
    • getSchemaName

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

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

      public String getColumnName(int i)
      Description copied from interface: ResultInterface
      Get the column name.
      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.
      Parameters:
      i - the column number (starting with 0)
      Returns:
      the column data type
    • isIdentity

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

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

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

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