### Database Schema:
CREATE TABLE game_publisher (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	game_id	INTEGER	NULL	DEFAULT NULL,
	publisher_id	INTEGER	NULL	DEFAULT NULL,
	foreign key (publisher_id) references publisher (id),
	foreign key (game_id) references game (id)
);

CREATE TABLE game_platform (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	game_publisher_id	INTEGER	NULL	DEFAULT NULL,
	platform_id	INTEGER	NULL	DEFAULT NULL,
	release_year	INTEGER	NULL	DEFAULT NULL,
	foreign key (platform_id) references platform (id),
	foreign key (game_publisher_id) references game_publisher (id)
);

CREATE TABLE platform (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	platform_name	TEXT	NULL	DEFAULT NULL
);

CREATE TABLE game (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	genre_id	INTEGER	NULL	DEFAULT NULL,
	game_name	TEXT	NULL	DEFAULT NULL,
	foreign key (genre_id) references genre (id)
);

CREATE TABLE genre (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	genre_name	TEXT	NULL	DEFAULT NULL
);

CREATE TABLE region (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	region_name	TEXT	NULL	DEFAULT NULL
);

CREATE TABLE region_sales (
	region_id	INTEGER	NULL	DEFAULT NULL,
	game_platform_id	INTEGER	NULL	DEFAULT NULL,
	num_sales	REAL	NULL	DEFAULT NULL,
	foreign key (region_id) references region (id),
	foreign key (game_platform_id) references game_platform (id)
);

CREATE TABLE publisher (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	publisher_name	TEXT	NULL	DEFAULT NULL
);

### User's Query:
Which year has the most number of PC games releases?

### Extra Knowledge:
year refers to release_year; the most number of releases refers to max(count(game_id))
SELECT T.release_year FROM ( SELECT T2.release_year, COUNT(DISTINCT T3.game_id) FROM platform AS T1 INNER JOIN game_platform AS T2 ON T1.id = T2.platform_id INNER JOIN game_publisher AS T3 ON T2.game_publisher_id = T3.id WHERE T1.platform_name = 'PC' GROUP BY T2.release_year ORDER BY COUNT(DISTINCT T3.game_id) DESC LIMIT 1 ) t