fix(planner): consider NULL for binary op in type checker

[xudong963]

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Summary

As the title

Changelog

• Bug Fix

Related Issues

Fixes #6038

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1 Ignored Deployment

Name	Status	Preview	Updated
databend	⬜️ Ignored (Inspect)		Jun 18, 2022 at 2:26AM (UTC)

[mergify]

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[sundy-li]

A test to cover :

set enable_planner_v2 = 1;
create table n( a int null, b int null) ;
insert into n select  if (number % 3, null, number), if (number % 2, null, number) from numbers(10);

select a + b, a and b, a - b, a or b from n;

set enable_planner_v2 = 0;
 select a + b, a and b, a - b, a or b  from n;

[xudong963]

All binary operators need to consider NULL, such as BinaryOperator::Plus, BinaryOperator::Minus, and so on. But part of them will be converted to function, so functions also need to consider NULL.
Updated: I noticed Function have processed NULL case 👍