MySQL: NOT LIKE
Solution 1:
categories_posts
and categories_news
start with substring 'categories_' then it is enough to check that developer_configurations_cms.cfg_name_unique
starts with 'categories' instead of check if it contains the given substring. Translating all that into a query:
SELECT *
FROM developer_configurations_cms
WHERE developer_configurations_cms.cat_id = '1'
AND developer_configurations_cms.cfg_variables LIKE '%parent_id=2%'
AND developer_configurations_cms.cfg_name_unique NOT LIKE 'categories%'
Solution 2:
I don't know why
cfg_name_unique NOT LIKE '%categories%'
still returns those two values, but maybe exclude them explicit:
SELECT *
FROM developer_configurations_cms
WHERE developer_configurations_cms.cat_id = '1'
AND developer_configurations_cms.cfg_variables LIKE '%parent_id=2%'
AND developer_configurations_cms.cfg_name_unique NOT LIKE '%categories%'
AND developer_configurations_cms.cfg_name_unique NOT IN ('categories_posts', 'categories_news')