MySQL Performance issue: select query takes forever - mysql

Question

This is vitally important query of the project that calculates statistic information for each user, generates almost 300k rows but it takes forever to get answer.
The problem is, this query is needed to be executed almost every 20-30 seconds and the row count always grows.
Despite the fact that the fields that used in join and where are indexed it takes around 2000 seconds to get the answer from query.
One another fact is, the tables used in this query are large. For example, IconKeyword holds almost 95M records.
Please take a look and tell me how can I optimize this query
SELECT
Icon.`user_id` AS user_id,
Keyword.`id` AS keyword_id,
Keyword.`title` AS keyword_title,
Keyword.`demand` AS keyword_demand,
count( IconKeyword.`iconID` ) AS ico_count,
Icon.`type` AS icon_type,
Keyword.`common` AS common
FROM
Icon
INNER JOIN IconKeyword ON IconKeyword.iconID = Icon.id
INNER JOIN Keyword ON Keyword.id = IconKeyword.keywordID
WHERE
Keyword.is_deleted = 0
AND
Keyword.restricted = 0
GROUP BY
Icon.`user_id`,
Icon.type,
Keyword.id;
And here is explain results:
Create tables:
CREATE TABLE `Icon` (
`id` int unsigned NOT NULL AUTO_INCREMENT,
`title` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`uri` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`description` text CHARACTER SET utf8 COLLATE utf8_general_ci,
`type` tinyint DEFAULT NULL,
`created_at` datetime DEFAULT NULL,
`updated_at` datetime DEFAULT NULL,
`user_id` int unsigned DEFAULT NULL,
`f_id` int unsigned DEFAULT NULL,
`color` tinyint unsigned DEFAULT '0',
`pack_id` int unsigned DEFAULT NULL,
`pack_bg` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`fi_url` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`is_deleted` tinyint unsigned DEFAULT '0',
`count_of_sets` int unsigned NOT NULL DEFAULT '0',
`p_hash` binary(64) DEFAULT NULL,
`hash_bit_count` int unsigned GENERATED ALWAYS AS (bit_count(`p_hash`)) STORED,
`checked` tinyint unsigned DEFAULT '0',
`md5` varchar(255) DEFAULT NULL,
PRIMARY KEY (`id`) USING BTREE,
UNIQUE KEY `f_id` (`f_id`) USING BTREE,
KEY `user_id` (`user_id`) USING BTREE,
KEY `id` (`id`,`type`,`user_id`) USING BTREE,
KEY `type` (`type`) USING BTREE,
KEY `uri` (`uri`) USING BTREE,
KEY `hash_bit_count` (`hash_bit_count`) USING BTREE,
KEY `is_deleted` (`is_deleted`),
KEY `checked` (`checked`),
KEY `user_id_2` (`user_id`,`type`) USING BTREE,
CONSTRAINT `Icon_ibfk_1` FOREIGN KEY (`user_id`) REFERENCES `User` (`id`) ON DELETE SET NULL ON UPDATE CASCADE
) ENGINE=InnoDB AUTO_INCREMENT=118691 DEFAULT CHARSET=utf8
CREATE TABLE `Keyword` (
`id` int unsigned NOT NULL AUTO_INCREMENT,
`title` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`slug` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`created_at` datetime DEFAULT CURRENT_TIMESTAMP,
`common` tinyint unsigned DEFAULT '0',
`demand` int DEFAULT '0',
`f_id` int unsigned DEFAULT NULL,
`is_deleted` tinyint unsigned DEFAULT '0',
`needs_review` tinyint unsigned DEFAULT '0',
`checked` tinyint unsigned DEFAULT '0',
`restricted` tinyint unsigned DEFAULT '0',
`word_checked` tinyint unsigned DEFAULT '0',
PRIMARY KEY (`id`) USING BTREE,
UNIQUE KEY `slug` (`slug`) USING BTREE,
KEY `title` (`title`) USING BTREE,
KEY `is_deleted` (`is_deleted`) USING BTREE,
KEY `restricted` (`restricted`) USING BTREE,
KEY `restricted_2` (`restricted`,`is_deleted`,`id`) USING BTREE
) ENGINE=InnoDB AUTO_INCREMENT=30000392 DEFAULT CHARSET=utf8
CREATE TABLE `IconKeyword` (
`iconID` int unsigned NOT NULL,
`keywordID` int unsigned NOT NULL,
PRIMARY KEY (`iconID`,`keywordID`) USING BTREE,
UNIQUE KEY `keywordID_2` (`keywordID`,`iconID`),
KEY `keywordID` (`keywordID`) USING BTREE,
KEY `iconID` (`iconID`) USING BTREE,
CONSTRAINT `ik_ibfk_1` FOREIGN KEY (`keywordID`) REFERENCES `Keyword` (`id`) ON DELETE CASCADE ON UPDATE CASCADE,
CONSTRAINT `ik_ibfk_2` FOREIGN KEY (`iconID`) REFERENCES `Icon` (`id`) ON DELETE CASCADE ON UPDATE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=utf8

Answer 1

For your query, you can try adding indexes on:
keyword(is_deleted, is_restricted, id)
IconKeyword(KeywordId, IconId)
Icon(id) (which should already exist because id is a primary key)
The query will still need to do a lot of work for the aggregation, but this might help.

Answer 2

I guess the number of records that have Keyword.is_deleted = 0 AND Keyword.restricted = 0 is quite large, so adding indexes here wouldn't help much.
What you can try is helping the aggregation works faster by adding a Multiple-Column Indexes, specifically (Icon.user_id, Icon.type) because it's what you're using in GROUP BY
Also, can you provide an EXPLAIN result of this query so we can better understand what is causing the performance problem.