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ŷ�����饹�� ɸ��δط�����ȼͱƤ��䤤��碌���䤤��碌�뤳�Ȥ��Ǥ��ޤ��� �����Ԥ��ˤ� SQL �� select ʸ��Ȥ��ޤ��� ʸ�ϥ������åȥꥹ��(�֤����°����ꥹ�ȥ��åפ��Ƥ���Ȥ���)�� �����(���¤���ꤷ�Ƥ���Ȥ���)��ʬ����ޤ��� ��Ȥ��ơ�ŷ���Τ��٤ƤιԤ���Ф��ˤϼ��Τ褦�˥����פ��ޤ�:

SELECT * FROM ŷ��;
�����ƽ��Ϥϼ��Τ褦�ˤʤ�ޤ�:
+-----------------+----------+----------+--------+------------+
|��               | ���㵤�� | �ǹⵤ�� | �߿��� | ����       |
+-----------------+----------+----------+--------+------------+
|����ե�󥷥��� | 46       | 50       | 0.25   | 11-27-1994 |
+-----------------+----------+----------+--------+------------+
|����ե�󥷥��� | 43       | 57       | 0      | 11-29-1994 |
+-----------------+----------+----------+--------+------------+
|�إ����       | 37       | 54       |        | 11-29-1994 |
+-----------------+----------+----------+--------+------------+
Ǥ�դμ��򥿡����åȥꥹ�Ȥ˻��ꤹ�뤳�Ȥ�Ǥ��ޤ��� �㤨�м��Τ褦�ˤǤ��ޤ�:
SELECT ��, (�ǹⵤ��+���㵤��)/2 AS ʿ�ѵ���, ���� FROM ŷ��;

Ǥ�դΥ֡��뷿�黻�� (and��or��not) ���䤤��碌�������˵�����Ƥ��ޤ��� �㤨�м��Τ褦�ˤʤ�ޤ�:

SELECT * FROM ŷ��
    WHERE �� = '����ե�󥷥���'
    AND �߿��� > 0.0;

+-----------------+----------+----------+--------+------------+
|��               | ���㵤�� | �ǹⵤ�� | �߿��� | ����       |
+-----------------+----------+----------+--------+------------+
|����ե�󥷥��� | 46       | 50       | 0.25   | 11-27-1994 |
+-----------------+----------+----------+--------+------------+

�Ǹ������Ȥ��ơ�����η�̤� ���֤��¤٤��� �⤷������ʣ�������󥹥����������� �褦�˻��ꤹ�뤳�Ȥ��Ǥ��ޤ���

SELECT DISTINCT ��
    FROM ŷ��
    ORDER BY ��;


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