MySQL是一個開源的關系型數據庫管理系統，常用于Web應用程序的數據存儲和管理。為了提高MySQL的查詢效率，經常需要對數據進行分表。下面介紹三種常見的MySQL分表方案：

方案一：按時間或編號分表

CREATE TABLE mytable_202101 (
id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
name VARCHAR(50) NOT NULL,
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE mytable_202102 (
id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
name VARCHAR(50) NOT NULL,
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE mytable_202103 (
id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
name VARCHAR(50) NOT NULL,
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

方案二：按數據量分表

CREATE TABLE mytable_01 (
id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
name VARCHAR(50) NOT NULL,
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE mytable_02 (
id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
name VARCHAR(50) NOT NULL,
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE mytable_03 (
id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
name VARCHAR(50) NOT NULL,
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
ALTER TABLE mytable_02 ENGINE=InnoDB;
ALTER TABLE mytable_03 ENGINE=InnoDB;
INSERT INTO mytable_02 SELECT * FROM mytable WHERE id >100000 AND id< 200000;
INSERT INTO mytable_03 SELECT * FROM mytable WHERE id >= 200000;

方案三：按Hash值分表

CREATE TABLE mytable_0 (
id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
name VARCHAR(50) NOT NULL,
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE mytable_1 (
id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
name VARCHAR(50) NOT NULL,
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE mytable_2 (
id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
name VARCHAR(50) NOT NULL,
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE mytable_3 (
id BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
name VARCHAR(50) NOT NULL,
PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
INSERT INTO mytable_0 SELECT * FROM mytable WHERE MOD(ABS(MD5(id)), 4) = 0;
INSERT INTO mytable_1 SELECT * FROM mytable WHERE MOD(ABS(MD5(id)), 4) = 1;
INSERT INTO mytable_2 SELECT * FROM mytable WHERE MOD(ABS(MD5(id)), 4) = 2;
INSERT INTO mytable_3 SELECT * FROM mytable WHERE MOD(ABS(MD5(id)), 4) = 3;

三種方案各有優缺點，需要根據業務需求進行選擇。同時，分表也會增加系統的復雜性，需要在設計時仔細考慮。