Create table with AUTO_INCREMENT as primary key
CREATE TABLE animals (
id MEDIUMINT NOT NULL AUTO_INCREMENT,
name CHAR(30) NOT NULL,
PRIMARY KEY (id)
);
Create table with Foreign Key
CREATE TABLE animals (
id MEDIUMINT NOT NULL AUTO_INCREMENT,
name CHAR(30) NOT NULL,
category int(11) NOT NULL,
PRIMARY KEY (id),
KEY fk_category (category),
CONSTRAINT fk_category FOREIGN KEY (category) REFERENCES category(id)
);
Alter table adding Foreign Key
ALTER TABLE animals CONSTRAINT fk_category FOREIGN KEY (category) REFERENCES category(id);
Alter column NOT NULL
ALTER TABLE animals MODIFY category int NOT NULL;
Alter column name from category to category
ALTER TABLE animals CHANGE category category int NOT NULL;
Reference:
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