8.7.1. Declaration of Enumerated Types
Enum types are created using the CREATE TYPE command, for example: 

CREATE TYPE mood AS ENUM ('sad', 'ok', 'happy');
Once created, the enum type can be used in table and function definitions much like any other type: 

Example 8.3. Basic Enum Usage

CREATE TYPE mood AS ENUM ('sad', 'ok', 'happy');
CREATE TABLE person (
    name text,
    current_mood mood
);
INSERT INTO person VALUES ('Moe', 'happy');
SELECT * FROM person WHERE current_mood = 'happy';
 name | current_mood 
------+--------------
 Moe  | happy
(1 row)

id | servername    | host  | user  | isDefault
1  | server 1      | tyr1  | u1    | 0
2  | server 2      | tyr2  | u2    | 0
3  | server 3      | tyr3  | u3    | 1
4  | server 4      | tyr4  | u4    | 0
5  | server 5      | tyr 5 | u5    | 0