Metadata
Create Table
create table employee (
person_name char(10),
street char(10),
city char(10),
salary real
);
Add Primary Key
alter table employee add primary key(person_name);
Add New Column
alter table employee add column salary real;
Delete Column
alter table employee drop city;
Drop Table
drop table employee;
Show table
desc employee;
Data
Show all data
select * from employee;
Add data
insert into employee values ('han mei', 'dagong rd', 'dalian', 6000), ('Li Lei', 'Hollywood Rd', 'LA');
Select data
find names of employees who live in Dalian
select person_name from employee where city = 'dalian';
select person_name from employee where street like 'Dagong rd';
select person_name from employee where salary > 10000;
Delete Data
delete from employee where street = 'Dagong rd';
Table with Foreign key
Cross-product
