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  • 统计sql

    查询统计信息

    select * from user_tab_statistics t
    where t.TABLE_NAME=upper('tablename');

    查询表基本信息

    select * from user_tab_statistics
    select table_name,num_rows,blocks,avg_row_len,sample_size,owner
    from all_tables/* where owner='NEO'*/
    where num_rows > 5000000

    执行统计函数
    exec dbms_stats.gather_table_stats(ownname=>'aneo_0905_3',tabname=>'chms_trade_cexecutions',cascade => true);

     查询索引状态

    select * from dba_indexes b

    1) create table ind (id int,name varchar2(100));

    2)

    SQL> begin
    2 for i in 1..10000 loop
    3 insert into ind values(i,to_char(i)||'aaa');
    4 end loop;
    5 commit;
    6 end;
    7 /

    3)create index ind_id_idx on ind(id);

    4)analyze index ind_id_idx validate structure;

    5)SELECT * from index_stats;

    6)

    SELECT name,del_lf_rows, lf_rows - del_lf_rows lf_rows_used,to_char(del_lf_rows / (lf_rows)*100,'999.99999') ibadness
     FROM index_stats where name = upper('&&index_name');

    analyze index ind_id_idx validate structure;
    select (del_lf_rows/lf_rows)*100 from index_stats ;
    alter index ind_id_idx coalesce;

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  • 原文地址:https://www.cnblogs.com/jjj250/p/9552248.html
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