有时候有这样的烦恼，由于dmp增量到数据库中，或是大批量数据操作后没有收集表的统计信息，导致数据库性能慢。要手工写脚本检查。

drop table gather_tcount;

create table gather_tcount

(

TABLE_NAME  VARCHAR2(30) not null,

gather_time date,

num_rows    number,

user_table_num_rows number

);

comment on table GATHER_TCOUNT

is '统计表的数据量，差距太大的需要收集统计信息';

alter table GATHER_TCOUNT

add constraint pk_gt_name_t primary key (TABLE_NAME, GATHER_TIME);

create or replace procedure p_gather_tcount

as

--统计实际表中数据量和统计信息表中数据量差异

--如果是重新统计，需要先清空gather_tcount的内容

--如果是断点续统计，不需要清空gather_tcount的内容

v_count number;

v_temp number;

v_tabname_temp varchar2(30);

begin

for c_rows in(select s.table_name,s.num_rows

from user_tables s  where s.table_name not like '%BAK%'

and s.table_name not like 'BK%' and

s.table_name not like '%TEMP')--过滤掉备份表

loop

v_tabname_temp := c_rows.table_name;

select count(1) into v_temp from gather_tcount where table_name = c_rows.table_name;

--如果是断点续统计，则不需要重新count表

if(v_temp =0) then

execute immediate 'select count(1) from '||c_rows.table_name into v_count;

execute immediate 'insert into gather_tcount(TABLE_NAME,gather_time,

num_rows,user_table_num_rows) values(:1,:2,:3,:4)'

using c_rows.table_name,sysdate,v_count,c_rows.num_rows;

commit;

end if;

end loop;

exception when others then

execute immediate 'insert into gather_tcount(TABLE_NAME,gather_time,

num_rows,user_table_num_rows) values(:1,:2,:3,:4)'

using v_tabname_temp,sysdate,sqlcode,sqlcode; --错误的先中断

commit;

end;

call p_gather_tcount(); select * from gather_tcount;