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–explain 查看 SQL 执行打算
EXPLAIN PLAN FOR select count(*) from steven.AWEN_OGG_TEST;
select * from table(dbms_xplan.display());
– 查看 AWR 和 CURSOR 中的执行打算
select * from table(dbms_xplan.display_awr(‘&sqlid’));
select * from table(dbms_xplan.display_cursor(‘&sqlid’));
– 查看游戏代理中内存中的执行打算
select ‘| Operation |Object Name | Rows | Bytes| Cost |’
as “Explain Plan in library cache:” from dual
union all
select rpad(‘| ‘||substr(lpad(‘ ‘,1*(depth-1))||operation||
decode(options, null,”,’ ‘||options), 1, 35), 36, ‘ ‘)||’|’||
rpad(decode(id, 0, ‘—————————-‘,
substr(decode(substr(object_name, 1, 7), ‘SYS_LE_’, null, object_name)
||’ ‘,1, 30)), 31, ‘ ‘)||’|’|| lpad(decode(cardinality,null,’ ‘,
decode(sign(cardinality-1000), -1, cardinality||’ ‘,
decode(sign(cardinality-1000000), -1, trunc(cardinality/1000)||’K’,
decode(sign(cardinality-1000000000), -1, trunc(cardinality/1000000)||’M’,
trunc(cardinality/1000000000)||’G’)))), 7, ‘ ‘) || ‘|’ ||
lpad(decode(bytes,null,’ ‘,
decode(sign(bytes-1024), -1, bytes||’ ‘,
decode(sign(bytes-1048576), -1, trunc(bytes/1024)||’K’,
decode(sign(bytes-1073741824), -1, trunc(bytes/1048576)||’M’,
trunc(bytes/1073741824)||’G’)))), 6, ‘ ‘) || ‘|’ ||
lpad(decode(cost,null,’ ‘, decodewww.walajiao.com(sign(cost-10000000), -1, cost||’ ‘,
decode(sign(cost-1000000000), -1, trunc(cost/1000000)||’M’,
trunc(cost/1000000000)||’G’))), 8, ‘ ‘) || ‘|’ as “Explain plan”
from v$sql_plan sp
where sp.hash_value=&hash_value or sp.sql_id=’&sqlid’;
– 查看历史执行打算
select distinct SQL_ID,PLAN_HASH_VALUE,to_char(TIMESTAMP,’yyyymmdd hh24:mi:ss’) TIMESTAMP
from dba_hist_sql_plan
where SQL_ID=’&sqlid’ order by TIMESTAMP;