I MySQL view constraints, add constraints, delete constraints

• View field information for table: DESC table name;
• View all information about the table: Show create table table name;
• Add PRIMARY KEY constraint: ALTER TABLE name add constraint primary key (Shape: Pk_ table name) primary key table name (primary key field);
• Add FOREIGN KEY constraint: ALTER TABLE from TABLE ADD constraint foreign key (shape: Fk_ from Table _ Main Table) foreign key from table (foreign key field) references Main Table (primary key field);
• Delete PRIMARY KEY constraint: ALTER TABLE name drop PRIMARY key;
• Delete FOREIGN KEY constraint: ALTER TABLE name drop FOREIGN key foreign key (case sensitive);

I MySQL view constraints, add constraints, delete constraints