Class SimplePredicate

    • Field Detail

      • left

        Expression left
        The left hand side of the expression.
      • not

        final boolean not
        Whether it is a "not" condition (e.g. "is not null").
      • whenOperand

        final boolean whenOperand
        Where this is the when operand of the simple case.
    • Constructor Detail

      • SimplePredicate

        SimplePredicate​(Expression left,
                        boolean not,
                        boolean whenOperand)
    • Method Detail

      • 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 b)
        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
        b - true if the table filter can return value
      • needParentheses

        public final boolean needParentheses()
        Description copied from class: Expression
        Returns whether this expressions needs to be wrapped in parentheses when it is used as an argument of other expressions.
        Overrides:
        needParentheses in class Expression
        Returns:
        true if it is
      • 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
      • 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
      • isEverything

        public boolean isEverything​(ExpressionVisitor visitor)
        Description copied from class: Expression
        Check if this expression and all sub-expressions can fulfill a criteria. If any part returns false, the result is false.
        Specified by:
        isEverything in class Expression
        Parameters:
        visitor - the visitor
        Returns:
        if the criteria can be fulfilled
      • getCost

        public int getCost()
        Description copied from class: Expression
        Estimate the cost to process the expression. Used when optimizing the query, to calculate the query plan with the lowest estimated cost.
        Specified by:
        getCost in class Expression
        Returns:
        the estimated cost
      • getSubexpressionCount

        public int getSubexpressionCount()
        Description copied from class: Expression
        Returns count of subexpressions.
        Overrides:
        getSubexpressionCount in class Expression
        Returns:
        count of subexpressions
      • getSubexpression

        public Expression getSubexpression​(int index)
        Description copied from class: Expression
        Returns subexpression with specified index.
        Overrides:
        getSubexpression in class Expression
        Parameters:
        index - 0-based index
        Returns:
        subexpression with specified index, may be null
      • isWhenConditionOperand

        public final boolean isWhenConditionOperand()
        Description copied from class: Expression
        Returns whether this expression is a right side of condition in a when operand.
        Overrides:
        isWhenConditionOperand in class Expression
        Returns:
        true if it is, false otherwise