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5.2. ��

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tgl=> SELECT text 'Origin' AS "Label", point '(0,0)' AS "Value";
 Label  | Value
--------+-------
 Origin | (0,0)
(1 row)

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PostgreSQL�Υѡ��ˤϡ��̤η��Ѵ��롼�뤬ɬ�פ�4�Ĥδ��Ū��SQL��Ǥ��ޤ��

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�ؿ��ƤӽФ�: PostgreSQL�η��ƥ��¿��ϡ�¿��δؿ��ν��äƹ��ۤ��Ƥ��ޤ��䤤��碌�ˤ��ؿ��ƤӽФ��ϰ��1�İʾ��ƥ५��ǻ��Ѳ�ǽ�Ȥ��Ƥ��ؿ��˰��פ��Ƥ��ʤ��Ф��ޤ�� PostgreSQL�ϴؿ��Υ��С��ɤ��Ĥ��Τǡ��ؿ�̾�ΤߤǤϸƤӽФ��ؿ��դ˼��̤��ޤ��󡣥ѡ��Ϳ��Υǡ��˴�Ť��ؿ��򤷤ʤ��Ф��ޤ��
�䤤��碌��о�: SQL��INSERT�� UPDATEʸ�ϼ��η�̤�ơ��֥��˳�Ǽ��ޤ��䤤��碌��μ��оݤȤʤ륫��η��˰��פ��롢�ޤ��ϡ��Ѵ��Ǥ��ΤǤ��ɬ�פ��ޤ��
UNION ��Ǥ� CASE ��: UNION��SELECTʸ��̤Ϥ��٤ơ��1�Ĥ��󽸹�˸��ʤ��Ф��ޤ��Τǡ��SELECT��η��줵�줿��˰��פ��Ѵ��Ǥ��ɬ�פ��ޤ��Ʊ�ͤˡ�CASE��ΤȤ��ƴ��Τν��Ϸ��Ĥ褦�ˤʤ뤿��ˡ�CASE��Ǥη�̼��϶��̤η��ɬ�פ��ޤ��

��Ū�ʷ��Ѵ��롼��¿��ϡ�PostgreSQL�ؿ��ȱ黻�ҤΥ��ƥ�ơ��֥��Ȥ߹��ޤ�Ƥ��ñ�ʵ��Ѥ��ޤ�� smallint��integer��real�Ȥ��ä�� SQLɸ��˸�ͭ�η��Ѥε��ꤦ�ޤ��ݡ��Ȥ��뤿��ˡ��Ѵ��롼��ˤ��̤��Ѱդ��줿��Τ⤢��ޤ��

PostgreSQL�ѡ��ϡ��٤Ƥη��Ѵ��ؿ��Ѵ��Ȥʤ뷿�ΰ��1�ĤȤꡢ�оݤȤ��뷿��Ʊ��̾��δؿ�̾�ȤʤäƤ��Ȥ��Ѥ��Ƥ��ޤ��δ��˽��ؿ��Ϥ��٤ơ�ͭ��Ѵ��ؿ��Ȥߤʤ��졢�ѡ��ˤ�ä��Ѵ��ؿ��Ȥ��ƻ��Ѥ��ǽ��ޤ��δ�ñ�ʲ��ˤ�äơ��ѡ��ϡ�ľ�ܥ��˵��Ҥ��뤳�Ȥʤ��Ѵ��ɽ��Ǥ��ޤ��Ǥ��顢��ĥ��줿�桼��Ϥ��ε�ǽ��Ʃ��Ū�˻��ѤǤ��櫓�Ǥ��

��ˡ�SQLɸ�෿�Ѥ�Ŭ�ڤ�ư��򤦤ޤ��¬�Ǥ��褦�ˤ��뤿��ȯ��Ū��ˡ��ѡ��󶡤��Ƥ��ޤ��Ū�� ��ƥ���ϡ��֡�������� ʸ�����ӥå�ʸ�������� ������إǡ�����ͥåȥ���� �桼����ޤ��桼��ƥ��ƥ��ϡ��ޤ��ͥ��Ū��򤵤����ޤ����ޤ��桼��ƥ��Ǥϡ��줾��η��Ϥ��켫�Ȥι��ޤ��Ǥ��ޤ��ʼ��ʣ��β��Ϸ�̸��Ĥ�Ρˤϡ�ʣ��β�ǽ��Ȥ߹��߷��ä��Ȥ��Ƥ⤷�Ф��в��Ǥ��ޤ��ʣ��Υ桼��褬��ˤϥ��顼��ȯ��ޤ��

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5.2. ����

5.2. ��