mysql去重后保存

-- 创建示例表
CREATE TABLE users (
    id INT AUTO_INCREMENT PRIMARY KEY,
    name VARCHAR(100),
    email VARCHAR(100)
);

-- 插入示例数据
INSERT INTO users (name, email) VALUES
('Alice', 'alice@example.com'),
('Bob', 'bob@example.com'),
('Alice', 'alice@example.com'),
('Charlie', 'charlie@example.com');

-- 单列去重
SELECT DISTINCT email FROM users;

-- 多列去重并保存到新表
CREATE TABLE unique_users AS
SELECT DISTINCT name, email FROM users;

-- 备份原始数据
CREATE TABLE users_backup AS SELECT * FROM users;

-- 进行去重操作
CREATE TABLE unique_users AS
SELECT DISTINCT name, email FROM users;

-- 确保所有相关列都被考虑
CREATE TABLE unique_users AS
SELECT DISTINCT name, email FROM users;