Class Operation0

    • Constructor Detail

      • Operation0

        protected Operation0()
    • Method Detail

      • mapColumns

        public void mapColumns​(ColumnResolver resolver,
                               int level,
                               int state)
        Description copied from class: Expression
        Map the columns of the resolver to expression columns.
        Specified by:
        mapColumns in class Expression
        Parameters:
        resolver - the column resolver
        level - the subquery nesting level
        state - current state for nesting checks, initial value is Expression.MAP_INITIAL
      • optimize

        public Expression optimize​(SessionLocal session)
        Description copied from class: Expression
        Try to optimize the expression.
        Specified by:
        optimize in class Expression
        Parameters:
        session - the session
        Returns:
        the optimized expression
      • setEvaluatable

        public void setEvaluatable​(TableFilter tableFilter,
                                   boolean value)
        Description copied from class: Expression
        Tell the expression columns whether the table filter can return values now. This is used when optimizing the query.
        Specified by:
        setEvaluatable in class Expression
        Parameters:
        tableFilter - the table filter
        value - true if the table filter can return value
      • updateAggregate

        public void updateAggregate​(SessionLocal session,
                                    int stage)
        Description copied from class: Expression
        Update an aggregate value. This method is called at statement execution time. It is usually called once for each row, but if the expression is used multiple times (for example in the column list, and as part of the HAVING expression) it is called multiple times - the row counter needs to be used to make sure the internal state is only updated once.
        Specified by:
        updateAggregate in class Expression
        Parameters:
        session - the session
        stage - select stage