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�);
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)