WITH "SubQueryNum_Expression_0_3279ed4e-7dbc-4f0f-9507-72a421b44449"

Question

WITH "SubQueryNum_Expression_0_3279ed4e-7dbc-4f0f-9507-72a421b44449"

AS (SELECT SUM("innerModelQuery"."Num") AS "Num_Expression_0_3279ed4e-7dbc-4f0f-9507-72a421b44449"
FROM (SELECT * FROM "fa2a3d48_datasource_191"."dataset_4548") AS "innerModelQuery"
WHERE (("innerModelQuery"."Section" IN ('left')))),
"SubQueryNum_Expression_0_514e3a3c-3846-4ca4-a6a7-d3e8140e9c44"
AS (SELECT SUM("innerModelQuery"."Num") AS "Num_Expression_0_514e3a3c-3846-4ca4-a6a7-d3e8140e9c44"
FROM (SELECT * FROM "fa2a3d48_datasource_191"."dataset_4548") AS "innerModelQuery"
WHERE (("innerModelQuery"."Section" IN ('right'))))
SELECT COALESCE(
"SubQueryNum_Expression_0_3279ed4e-7dbc-4f0f-9507-72a421b44449"."Num_Expression_0_3279ed4e-7dbc-4f0f-9507-72a421b44449",
0) AS "А",
COALESCE(
"SubQueryNum_Expression_0_514e3a3c-3846-4ca4-a6a7-d3e8140e9c44"."Num_Expression_0_514e3a3c-3846-4ca4-a6a7-d3e8140e9c44",
10) AS "B"
FROM "SubQueryNum_Expression_0_3279ed4e-7dbc-4f0f-9507-72a421b44449"
LEFT JOIN "SubQueryNum_Expression_0_514e3a3c-3846-4ca4-a6a7-d3e8140e9c44" ON 1 = 1
WHERE true

Вот этот запрос вернет для первого 8, для второго 10
Если убрать WHERE true то для первого 8, а для второго -9

Почему WHERE true как будто обращает в нулл значение из COALESCE “B” ?