Mysql Select query with double JOIN statement - mysql

Question

Hy guys. I need to select the customer_id who is on 'base' table, where the created date is the current date and where this customer dont have a budget_item executed on the current date. My query brings up an incorrect result. It show the customer_id of all budget_id that are not on that date..
What is wrong in my stetement?
PS.: I cannot consolidate the tables.
SELECT base.customer_id
FROM base
LEFT JOIN budget ON base.customer_id = budget.customer_id
LEFT JOIN budget_item ON budget.budget_id = budget_item.budget_id
WHERE
CAST(base.created as Date) = CURDATE()
AND budget_item.execution_date <> CURDATE();

Answer 1

Left join budget/budget_item specifically looking for items with the current date and then exclude them in WHERE by checking that some non-nullable column of budget_item is NULL (indicating no record was joined):
SELECT base.customer_id
FROM base
LEFT JOIN budget ON base.customer_id = budget.customer_id
LEFT JOIN budget_item ON budget.budget_id = budget_item.budget_id AND budget_item.execution_date = CURDATE()
WHERE
CAST(base.created as Date) = CURDATE()
AND budget_item.budget_id IS NULL;
Some prefer using NOT EXISTS for this, but the result and efficiency should be the same:
SELECT base.customer_id
FROM base
WHERE
CAST(base.created as Date) = CURDATE()
AND NOT EXISTS (
SELECT 1
FROM budget
JOIN budget_item ON budget.budget_id = budget_item.budget_id AND budget_item.execution_date = CURDATE()
WHERE budget.customer_id = base.customer_id
);
fiddle

Answer 2

Use aggregation:
SELECT base.customer_id
FROM base LEFT JOIN
budget bu
ON base.customer_id = bu.customer_id LEFT JOIN
budget_item bi
ON bu.budget_id = bi.budget_id
WHERE CAST(base.created as Date) = CURDATE()
GROUP BY base.customer_id
HAVING SUM(bi.execution_date = CURDATE()) = 0;