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使用remove_constants工具查看Oracle是否使用绑定变量
https://asktom.oracle.com/pls/asktom/f?p=100:11:::::P11_QUESTION_ID:1163635055580
http://blog.csdn.net/zq9017197/article/details/7690061
1、首先创建一个表,用于存放整理过的数据:
create table t1 as select sql_text from v$sqlarea;
2、给表增加一个字段:
alter table t1 add sql_text_wo_constants varchar2(1000);
3、创建函数remove_constants:
create or replace function
remove_constants( p_query in varchar2 ) return varchar2
as
l_query long;
l_char varchar2(1);
l_in_quotes boolean default FALSE;
begin
for i in 1 .. length( p_query )
loop
l_char := substr(p_query,i,1);
if ( l_char = ‘‘‘‘ and l_in_quotes )
then
l_in_quotes := FALSE;
elsif ( l_char = ‘‘‘‘ and NOT l_in_quotes )
then
l_in_quotes := TRUE;
l_query := l_query || ‘‘‘#‘;
end if;
if ( NOT l_in_quotes ) then
l_query := l_query || l_char;
end if;
end loop;
l_query := translate( l_query, ‘0123456789‘, ‘@@@@@@@@@@‘ );
for i in 0 .. 8 loop
l_query := replace( l_query, lpad(‘@‘,10-i,‘@‘), ‘@‘ );
l_query := replace( l_query, lpad(‘ ‘,10-i,‘ ‘), ‘ ‘ );
end loop;
return upper(l_query);
end;
/
4、将v$sql视图中的字段:sql_text的数据用remove_constants处理后,来更新t1表
update t1 set sql_text_wo_constants = remove_constants(sql_text);
5、查出除了谓词条件不同的SQL语句和它们的执行次数,这里是查询SQL没有重用超过100次的SQL语句:
select sql_text_wo_constants, count(*)
from t1
group by sql_text_wo_constants
having count(*) > 100
order by 2
/
使用remove_constants工具查看Oracle是否使用绑定变量