Oracle SQL Performance Analyzer的使用
通过 SPA，您可以根据各种更改类型（如初始化参数更改、优化器统计刷新和数据库升级）播放特定的 SQL 或整个 SQL 负载，然后生成比较报告，帮助您评估它们的影响。
在 Oracle Database 11g 之前的版本中，我必须捕获所有 SQL 语句，通过跟踪运行这些语句， 然后得到执行计划 — 这是一项极其耗时又极易出错的任务。新版本中，我们不需要再那样做了， 我改用非常简单而有效的 SQL Performance Analyzer。
update t1 set sname='苏州' where sid=500001;
update t1 set sname='南京' where sid=600001;
---3.收集统计信息
exec dbms_stats.gather_table_stats(USER,'T1',CASCADE=>TRUE)
alter system flush shared_pool;
---4.执行查询
select count(*) from t1 where sid<=100;
select count(*) from t1 where sid<=500;
select count(*) from t1 where sid>50000;
---5.新建STS
BEGIN
DBMS_SQLTUNE.DROP_SQLSET(
sqlset_name => 'OCPYANG_STS'
);
END;
/
BEGIN
DBMS_SQLTUNE.CREATE_SQLSET(
sqlset_name => 'OCPYANG_STS',
sqlset_owner => 'SYS',
description => 'ocpyangtest');
END;
/
---6.加载sql优化集
set serveroutput on
DECLARE
cur01 dbms_sqltune.sqlset_cursor;
BEGIN
open cur01 for select value(a) from table(dbms_sqltune.select_cursor_cache
(
basic_filter => 'sql_text like ''%T1%'' and parsing_schema_name =''SYS''',
attribute_list => 'ALL'
)
) a;
dbms_sqltune.load_sqlset(
sqlset_name => 'OCPYANG_STS',
populate_cursor => cur01);
close cur01;
END;
/
/*********有两个参数值得特别说明：
1）SELECT_CURSOR_CACHE的第一个参数是basic_filter ，它可以取的值有：
sql_id VARCHAR(13),
force_matching_signature NUMBER,
sql_text CLOB,
object_list sql_objects,
bind_data RAW(2000),
parsing_schema_name VARCHAR2(30),
module VARCHAR2(48),
action VARCHAR2(32),
elapsed_time NUMBER,
cpu_time NUMBER,
buffer_gets NUMBER,
disk_reads NUMBER,
direct_writes NUMBER,
rows_processed NUMBER,
fetches NUMBER,
executions NUMBER,
end_of_fetch_count NUMBER,
optimizer_cost NUMBER,
optimizer_env RAW(1000),
priority NUMBER,
command_type NUMBER,
first_load_time VARCHAR2(19),
stat_period NUMBER,
active_stat_period NUMBER,
other CLOB,
plan_hash_value NUMBER,
sql_plan sql_plan_table_type,
bind_list sql_binds
2）SELECT_CURSOR_CACHE的最后一个参数是attribute_list
BASIC (default) -all attributes (such as execution statistics and binds) are returned except the plans The execution context is always part of the result.
TYPICAL - BASIC + SQL plan (without row source statistics) and without object reference list
ALL - return all attributes
Comma separated list of attribute names this allows to return only a subset of SQL attributes: EXECUTION_STATISTICS, BIND_LIST, OBJECT_LIST, SQL_PLAN,SQL_PLAN_STATISTICS: similar to SQL_PLAN + row source statistics
*********/