oracle的转义字符是什么

update userinfo set pageurl='myjsp?page=1&pagesize=10' where id='test'

select * from ng_values where name like 'lady_%'

select ... from ... where ... like '/_%' escape '/';

insert into t(col) values(chr(ascii('&'))) ；

SQL> SHOW DEFINE
define "&" (hex 26) ? <--- DEFINE的default值是 ‘&’
SQL> SET DEFINE OFF
SQL> SHOW DEFINE
define OFF
SQL> INSERT INTO <table_name> VALUES (&#39;AT&T&#39;);

SQL> SHOW ESCAPE
escape OFF <--- ESCAPE的default值是 OFF
SQL> SET ESCAPE ON
SQL> SHOW ESCAPE
escape "\" (hex 5c)
SQL> INSERT INTO temp_table VALUES (&#39;select * from emp where ename =\&1&#39;);

SELECT 'myjsp?page=1&pagesize=10' FROM dual;
SELECT 'myjsp?page=1&pagesize=10' FROM dual;
SQL>   create   table   a  (b   varchar2(10));  
Table   created  
SQL>   insert   into   a  values('_a');

SQL>   select   B   from  A   where   instr(b,'_a')>0;  
B  
----------  
_a  
select   B   from   A  where   b   like   '%\_a%'  escape   '\'

select   B   from   A  where   b   like   '%\_a%'  escape   '\';
select   B   from   A  where   b   like   '%\_a%'  escape   '\';

Select 'abc' a,'' b, '''' c, ' '' ' d From Dual;

Select 'name' || '''''' a, 'name''''' b From Dual;
Output:name''　　name''

Select 'hh24"小时""mi""分"""ss"秒"' Results From Dual;
Output:hh24"小时""mi""分"""ss"秒"

Select Chr(38) a, 'Tom&&Jerry' b, 'Gun ''N Roses' c From Dual;
Output:&    Tom&Jerry    Gun 'N Roses

Select Table_Name From User_Tables Where Table_Name Like 'TB=_%=_%' Escape '=';
Output:TB_STUDENT_SCORE--筛选以TB开头,中间有两个_的表名