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CREATE TYPE mood AS ENUM ('sad', 'ok', 'happy');
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INSERT INTO person VALUES ('Larry', 'sad'); INSERT INTO person VALUES ('Curly', 'ok'); SELECT * FROM person WHERE current_mood > 'sad'; name | current_mood -------+-------------- Moe | happy Curly | ok (2 rows) SELECT * FROM person WHERE current_mood > 'sad' ORDER BY current_mood; name | current_mood -------+-------------- Curly | ok Moe | happy (2 rows) SELECT name FROM person WHERE current_mood = (SELECT MIN(current_mood) FROM person); name ------- Larry (1 row)
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例 8-5. ���㥹�Ȥη���
CREATE TYPE happiness AS ENUM ('happy', 'very happy', 'ecstatic'); CREATE TABLE holidays ( num_weeks int, happiness happiness ); INSERT INTO holidays(num_weeks,happiness) VALUES (4, 'happy'); INSERT INTO holidays(num_weeks,happiness) VALUES (6, 'very happy'); INSERT INTO holidays(num_weeks,happiness) VALUES (8, 'ecstatic'); INSERT INTO holidays(num_weeks,happiness) VALUES (2, 'sad'); ERROR: invalid input value for enum happiness: "sad" SELECT person.name, holidays.num_weeks FROM person, holidays WHERE person.current_mood = holidays.happiness; ERROR: operator does not exist: mood = happiness
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��Υ�٥�Ǥ���ʸ����ʸ������̤��ޤ��� ���Τ���'happy'��'HAPPY'��Ʊ���ǤϤ���ޤ��� ��٥���ζ���ʸ�����̣������ޤ���