MySQL 5.7

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-- структура 

CREATE TABLE `data` (
    `id` int(11) UNSIGNED NOT NULL AUTO_INCREMENT,
    `content` text NOT NULL,
        PRIMARY KEY (`id`)
) ENGINE = InnoDB;

CREATE TABLE `hub` (
`page` varchar(64) NOT NULL,
`section` int(11) UNSIGNED NULL DEFAULT NULL,
`data` int(11) UNSIGNED NULL,
    UNIQUE (`page`, `section`, `data`) USING BTREE,
    INDEX `page-I`(`page`) USING BTREE,
    INDEX `section-I`(`section`) USING BTREE,
    INDEX `data-I`(`data`) USING BTREE,
    CONSTRAINT `page-FK` FOREIGN KEY (`data`)
        REFERENCES `data` (`id`) ON DELETE CASCADE ON UPDATE RESTRICT               
) ENGINE = InnoDB;

CREATE TABLE `section` (
    `id` int(11) UNSIGNED NOT NULL AUTO_INCREMENT,
    `title` varchar(255) NOT NULL DEFAULT '',
        PRIMARY KEY (`id`)
) ENGINE = InnoDB;
ALTER TABLE hub 
    ADD FOREIGN KEY (section) REFERENCES section (id);

Records: 0  Duplicates: 0  Warnings: 0


-- исходные данные

INSERT INTO section VALUES
(1,	'foo'),
(2,	'bar'),
(3,	'baz');

INSERT INTO data VALUES
(1,	'some text - 1'),
(2,	'some text - 2'),
(3,	'some text - 3'),
(4,	'some text - 4'),
(5,	'some text - 5');

INSERT INTO hub (`page`, `data`, `section`) VALUES
('index',	1,	NULL),
('about',	2,	1),
('about',	3,	1),
('about',	4,	NULL),
('contacts',	5,	2),
('contacts',	NULL,	1);

Records: 3  Duplicates: 0  Warnings: 0



Records: 5  Duplicates: 0  Warnings: 0



Records: 6  Duplicates: 0  Warnings: 0


-- просмотр исходного состояния

SELECT * FROM section;
SELECT * FROM data;
SELECT * FROM hub;


id
title


1
foo

2
bar

3
baz




id
content


1
some text - 1

2
some text - 2

3
some text - 3

4
some text - 4

5
some text - 5




page
section
data


about
null
4

about
1
2

about
1
3

contacts
1
null

contacts
2
5

index
null
1


-- посмотрим, что собираемся удалять

SELECT * 
FROM data
LEFT JOIN hub ON data.id = hub.data
LEFT JOIN section ON section.id = hub.section
WHERE data.id IN(2,5)


id
content
page
section
data
id
title


2
some text - 2
about
1
2
1
foo

5
some text - 5
contacts
2
5
2
bar


-- удаляем

DELETE IGNORE data, hub, section
FROM data
LEFT JOIN hub ON data.id = hub.data
LEFT JOIN section ON section.id = hub.section
WHERE data.id IN(2,5)
-- смотрим, что осталось

SELECT * FROM section;
SELECT * FROM data;
SELECT * FROM hub;


id
title


1
foo

3
baz




id
content


1
some text - 1

3
some text - 3

4
some text - 4




page
section
data


about
null
4

about
1
3

contacts
1
null

index
null
1
id	content
1	some text - 1
2	some text - 2
3	some text - 3
4	some text - 4
5	some text - 5
page	section	data
about	null	4
about	1	2
about	1	3
contacts	1	null
contacts	2	5
index	null	1