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drop table ͪߩѦ���;
ERROR: table "ͪߩѦ���" does not exist
create table ͪߩѦ��� (��� text, ���ڵ� varchar, ���1A�� char(16));
create index ͪߩѦ���index1 on ͪߩѦ��� using btree (���);
create index ͪߩѦ���index2 on ͪߩѦ��� using hash (���ڵ�);
WARNING: hash indexes are not WAL-logged and their use is discouraged
insert into ͪߩѦ��� values('��ǻ�͵��÷���', 'ѦA01߾');
insert into ͪߩѦ��� values('��ǻ�ͱ��Ƚ�', '��B10��');
insert into ͪߩѦ��� values('��ǻ�����α���', '��Z01��');
vacuum ͪߩѦ���;
select * from ͪߩѦ���;
��� | ���ڵ� | ���1a��
------------------+----------+------------
��ǻ�͵��÷��� | ѦA01߾ |
��ǻ�ͱ��Ƚ� | ��B10�� |
��ǻ�����α��� | ��Z01�� |
(3 rows)
select * from ͪߩѦ��� where ���ڵ� = '��Z01��';
��� | ���ڵ� | ���1a��
------------------+----------+------------
��ǻ�����α��� | ��Z01�� |
(1 row)
select * from ͪߩѦ��� where ���ڵ� ~* '��z01��';
��� | ���ڵ� | ���1a��
------------------+----------+------------
��ǻ�����α��� | ��Z01�� |
(1 row)
select * from ͪߩѦ��� where ���ڵ� like '_Z01_';
��� | ���ڵ� | ���1a��
------------------+----------+------------
��ǻ�����α��� | ��Z01�� |
(1 row)
select * from ͪߩѦ��� where ���ڵ� like '_Z%';
��� | ���ڵ� | ���1a��
------------------+----------+------------
��ǻ�����α��� | ��Z01�� |
(1 row)
select * from ͪߩѦ��� where ��� ~ '��ǻ��[���]';
��� | ���ڵ� | ���1a��
------------------+----------+------------
��ǻ�͵��÷��� | ѦA01߾ |
��ǻ�ͱ��Ƚ� | ��B10�� |
(2 rows)
select * from ͪߩѦ��� where ��� ~* '��ǻ��[���]';
��� | ���ڵ� | ���1a��
------------------+----------+------------
��ǻ�͵��÷��� | ѦA01߾ |
��ǻ�ͱ��Ƚ� | ��B10�� |
(2 rows)
select *,character_length(���) from ͪߩѦ���;
��� | ���ڵ� | ���1a�� | character_length
------------------+----------+------------+------------------
��ǻ�͵��÷��� | ѦA01߾ | | 8
��ǻ�ͱ��Ƚ� | ��B10�� | | 7
��ǻ�����α��� | ��Z01�� | | 8
(3 rows)
select *,octet_length(���) from ͪߩѦ���;
��� | ���ڵ� | ���1a�� | octet_length
------------------+----------+------------+--------------
��ǻ�͵��÷��� | ѦA01߾ | | 16
��ǻ�ͱ��Ƚ� | ��B10�� | | 14
��ǻ�����α��� | ��Z01�� | | 16
(3 rows)
select *,position('��' in ���) from ͪߩѦ���;
��� | ���ڵ� | ���1a�� | position
------------------+----------+------------+----------
��ǻ�͵��÷��� | ѦA01߾ | | 4
��ǻ�ͱ��Ƚ� | ��B10�� | | 0
��ǻ�����α��� | ��Z01�� | | 0
(3 rows)
select *,substring(��� from 3 for 4) from ͪߩѦ���;
��� | ���ڵ� | ���1a�� | substring
------------------+----------+------------+-----------
��ǻ�͵��÷��� | ѦA01߾ | | �͵���
��ǻ�ͱ��Ƚ� | ��B10�� | | �ͱ���
��ǻ�����α��� | ��Z01�� | | �����α�
(3 rows)
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