MySQL 8.0

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create table employee(
emp_id numeric(4),
fname varchar(10),
lname varchar(10),
mgr_id numeric(4),
hire_date date,
job_id numeric(2),
dept_id numeric(3)
);




show create table employee;


Table
Create Table


employee
CREATE TABLE `employee` (
  `emp_id` decimal(4,0) DEFAULT NULL,
  `fname` varchar(10) DEFAULT NULL,
  `lname` varchar(10) DEFAULT NULL,
  `mgr_id` decimal(4,0) DEFAULT NULL,
  `hire_date` date DEFAULT NULL,
  `job_id` decimal(2,0) DEFAULT NULL,
  `dept_id` decimal(3,0) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci


ALTER TABLE employee ALTER COLUMN dept_id set default 111;

Records: 0  Duplicates: 0  Warnings: 0


show create table employee;


Table
Create Table


employee
CREATE TABLE `employee` (
  `emp_id` decimal(4,0) DEFAULT NULL,
  `fname` varchar(10) DEFAULT NULL,
  `lname` varchar(10) DEFAULT NULL,
  `mgr_id` decimal(4,0) DEFAULT NULL,
  `hire_date` date DEFAULT NULL,
  `job_id` decimal(2,0) DEFAULT NULL,
  `dept_id` decimal(3,0) DEFAULT '111'
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci


ALTER TABLE employee MODIFY COLUMN dept_id  int(8);

Records: 0  Duplicates: 0  Warnings: 1


ALTER TABLE employee CHANGE dept_id dept_id  int(5);

Records: 0  Duplicates: 0  Warnings: 1


show create table employee;


Table
Create Table


employee
CREATE TABLE `employee` (
  `emp_id` decimal(4,0) DEFAULT NULL,
  `fname` varchar(10) DEFAULT NULL,
  `lname` varchar(10) DEFAULT NULL,
  `mgr_id` decimal(4,0) DEFAULT NULL,
  `hire_date` date DEFAULT NULL,
  `job_id` decimal(2,0) DEFAULT NULL,
  `dept_id` int DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci