MySQL 复制表概述之结构、数据及索引的完整复制

-- 步骤1：获取原表结构
mysql> SHOW CREATE TABLE employees \G;
*************************** 1. row ***************************
       Table: employees
Create Table: CREATE TABLE `employees` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(50) NOT NULL,
  `department` varchar(30) DEFAULT NULL,
  `salary` decimal(10,2) DEFAULT NULL,
  PRIMARY KEY (`id`),
  KEY `idx_department` (`department`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4

-- 步骤2：创建新表结构
CREATE TABLE employees_copy (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(50) NOT NULL,
  `department` varchar(30) DEFAULT NULL,
  `salary` decimal(10,2) DEFAULT NULL,
  PRIMARY KEY (`id`),
  KEY `idx_department` (`department`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- 步骤3：复制数据
INSERT INTO employees_copy 
SELECT * FROM employees;

CREATE TABLE new_table LIKE original_table;

CREATE TABLE employees_clone LIKE employees;
INSERT INTO employees_clone SELECT * FROM employees;

mysqldump -u username -p database_name original_table > table_dump.sql

mysql -u username -p database_name < table_dump.sql

-- 复制特定列
CREATE TABLE partial_copy AS
SELECT id, name FROM employees WHERE department = 'IT';

-- 复制满足条件的行
INSERT INTO employees_copy
SELECT * FROM employees WHERE salary > 5000;

-- 在同一MySQL实例中
CREATE TABLE database2.new_table LIKE database1.original_table;
INSERT INTO database2.new_table SELECT * FROM database1.original_table;

-- 不同MySQL实例间
# 导出
mysqldump -u user1 -p db1 table1 > table1_dump.sql
# 导入
mysql -u user2 -p db2 < table1_dump.sql

-- 复制表但修改某些列
CREATE TABLE modified_copy (
  id INT PRIMARY KEY AUTO_INCREMENT,
  full_name VARCHAR(100) NOT NULL COMMENT '将first+last合并',
  department VARCHAR(50),
  monthly_salary DECIMAL(10,2),
  INDEX idx_dept (department)
) AS
SELECT 
  id, 
  CONCAT(first_name, ' ', last_name) AS full_name,
  department,
  salary/12 AS monthly_salary
FROM employees;

-- 方法1：分批插入
INSERT INTO large_table_copy 
SELECT * FROM large_table LIMIT 0, 10000;
INSERT INTO large_table_copy 
SELECT * FROM large_table LIMIT 10000, 10000;
-- 重复直到所有数据复制完成

-- 方法2：禁用索引优化
ALTER TABLE large_table_copy DISABLE KEYS;
INSERT INTO large_table_copy SELECT * FROM large_table;
ALTER TABLE large_table_copy ENABLE KEYS;

-- 方法3：使用临时文件
SELECT * FROM large_table INTO OUTFILE '/tmp/large_table_data.csv';
LOAD DATA INFILE '/tmp/large_table_data.csv' INTO TABLE large_table_copy;

-- 保留原自增ID
CREATE TABLE new_table LIKE original_table;
INSERT INTO new_table SELECT * FROM original_table;

-- 重置自增ID
CREATE TABLE new_table LIKE original_table;
ALTER TABLE new_table AUTO_INCREMENT=1;
INSERT INTO new_table (col1, col2) SELECT col1, col2 FROM original_table;

-- 方法1
CREATE TABLE new_table LIKE original_table;

-- 方法2
CREATE TABLE new_table AS SELECT * FROM original_table WHERE 1=0;

-- 方法3（使用mysqldump）
mysqldump -d -u username -p dbname original_table > table_structure.sql
mysql -u username -p dbname < table_structure.sql

-- 使用事务分批提交
START TRANSACTION;
INSERT INTO new_table SELECT * FROM original_table WHERE id BETWEEN 1 AND 10000;
COMMIT;

START TRANSACTION;
INSERT INTO new_table SELECT * FROM original_table WHERE id BETWEEN 10001 AND 20000;
COMMIT;
-- 继续直到完成