Oracle9i, 10g 優化分析統計(dbms_stats)指令碼

 

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Oracle9i (未開啟table monitoring時) 
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索引全分析
表分兩種，大表10%，小表100%

 

#start
$ORACLE_HOME/bin/sqlplus /nolog <connect user/xxxx
prompt "analyze start,please wait......"
set serveroutput on size 100000
declare
  v_per   number(3);
  v_start number := dbms_utility.get_time;
  v_time  number;
begin

for rec in (select segment_name,segment_type,ceil(sum(bytes)/1024/1024) segment_size
  from user_segments
  where segment_type like 'TABLE%' or segment_type like 'INDEX%'
  group by segment_name,segment_type)
loop
    --start analyze
    if rec.segment_type = 'INDEX' then
         dbms_stats.gather_index_stats(ownname => 'USER',
                                       indname => rec.segment_name,
                                       degree  => 8
                                      );
    elsif rec.segment_type = 'INDEX PARTITION' then
         dbms_stats.gather_index_stats(ownname => 'USER',
                                       indname => rec.segment_name,
                                       degree  => 8
                                      );
    elsif rec.segment_type = 'TABLE' then
        case when rec.segment_size < 100 then
            v_per := 100;
        else
            v_per := 10;
        end case;
             dbms_stats.gather_table_stats(ownname          => 'USER',
                                           tabname          => rec.segment_name,
                                           estimate_percent => v_per,
                                           method_opt       => 'FOR ALL COLUMNS SIZE 1',       -- SIZE 1 不收集直方圖資訊
                                           degree           => 8);
    elsif rec.segment_type = 'TABLE PARTITION' then
             v_per := 10;
             dbms_stats.gather_table_stats(ownname          => 'USER',
                                           tabname          => rec.segment_name,
                                           estimate_percent => v_per,
                                           method_opt       => 'FOR ALL COLUMNS SIZE 1',
                                           degree           => 8);
    end if;
   v_time  := ceil((dbms_utility.get_time - v_start)/100);
   dbms_output.put_line(rpad(rec.segment_name||'('||rec.segment_size||'M)',40,'.')||'elaped time '||v_time||'s');
   v_start := dbms_utility.get_time;
end loop;
end;
/
prompt "analyze end"
exit
EOF
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--------------------------------------------------------------
Oracle9i,10g (開啟table monitoring時) 
--------------------------------------------------------------

都採用auto方式。

SQL> being
 dbms_stats.gather_schema_stats(
 ownname => 'USER',
 estimate_percent => dbms_stats.auto_sample_size,    -- Oracle根據表的大小和列值分佈在5％到20％間取值
 method_opt => 'for all columns size auto',        
 cascade=>TRUE,
 degree => 8 );
     end;
     /

 

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