Week 01 Lecture (18)

Data Definition

Relational data: relations/tables, tuples, values, types, e.g.

create domain WAMvalue float
   check (value between 0.0 and 100.0);

create table Students (
   id          integer,  -- e.g. 3123456
   familyName  text,     -- e.g. 'Smith'
   givenName   text,     -- e.g. 'John'
   birthDate   date,     -- e.g. '1-Mar-1984'
   wam         WAMvalue, -- e.g. 85.4
   primary key (id)
);

The above adds meta-data to the database.

DBMSs typically store meta-data as special tables (catalog).