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
/

posted @ 2014-10-29 22:20  许志伟  阅读(436)  评论(0编辑  收藏  举报