[20181105]再论12c set feedback only.txt

[20181105]再论12c set feedback only.txt

--//前一阵子的测试,链接:http://blog.itpub.net/267265/viewspace-2216290/
--//12cr2 ,增强了set feedback功能,加入only选项可以禁止输出信息显示,仅仅显示返回几行,有利于dba集中精力调试
--//sql语句,18c还增加返回执行语句的sql_id的功能,简单测试.

--//我一直以为这种功能是针对特定版本的比如仅仅对12c有效,实际上如果你使用12c的客户端连接11g,执行set feedback only应该不支持.
--//通过测试说明问题.

1.环境:
d:\temp>sqlplus scott/book@78
sql*plus: release 12.2.0.1.0 production on 星期一 11月 5 10:47:35 2018
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
copyright (c) 1982, 2016, oracle.  all rights reserved.
连接到:
oracle database 11g enterprise edition release 11.2.0.4.0 - 64bit production
with the partitioning, olap, data mining and real application testing options

scott@78> @ ver1
port_string                    version        banner
------------------------------ -------------- --------------------------------------------------------------------------------
x86_64/linux 2.4.xx            11.2.0.4.0     oracle database 11g enterprise edition release 11.2.0.4.0 - 64bit production

--//我刚刚在办法环境重新安装12cr2版本.使用sqlplus连接11g.

scott@78> set feedback only
scott@78> select * from emp;
     empno ename      job              mgr hiredate                   sal       comm     deptno
---------- ---------- --------- ---------- ------------------- ---------- ---------- ----------

已选择 14 行。
--//没有多余的显示.

scott@78> set feedback 6
scott@78> @ dpc '' ''
plan_table_output
-------------------------------------
sql_id  a2dk8bdn0ujx7, child number 0
-------------------------------------
select * from emp
plan hash value: 3956160932
---------------------------------------------------------------------------
| id  | operation         | name | e-rows |e-bytes| cost (%cpu)| e-time   |
---------------------------------------------------------------------------
|   0 | select statement  |      |        |       |     3 (100)|          |
|   1 |  table access full| emp  |     14 |   532 |     3   (0)| 00:00:01 |
---------------------------------------------------------------------------
query block name / object alias (identified by operation id):
-------------------------------------------------------------
   1 - sel$1 / emp@sel$1

2.补充测试连接的http://blog.itpub.net/267265/viewspace-2216326/特性是否有效:
scott@78> set history 10
scott@78> select sysdate from dual ;
sysdate
-------------------
2018-11-05 10:51:00

scott@78> select user from dual ;
user
------------------------------
scott

scott@78> history
  1  select sysdate from dual ;
  2  select user from dual ;

--//可以发现一样有效.

scott@78> variable b number = 20;
scott@78> select * from dept where deptno = :b ;
    deptno dname          loc
---------- -------------- -------------
        20 research       dallas

--//这样定义变量也没有问题.

3.最后测试statement caching:
--//statement caching有点像软软解析.

scott@78> @ spid
       sid    serial# process                  server    spid       pid  p_serial# c50
---------- ---------- ------------------------ --------- ------ ------- ---------- ----------------------------------------------
        41          7 5512:516                 dedicated 62921       27          3 alter system kill session '41,7' immediate;
variable b number = 20;
select * from dept where deptno = :b ;
select * from dept where deptno = :b ;

--//通过查询执行计划,确定sql_id=2b073tss4h1f3.

scott@78> select sql_id,executions,parse_calls,sql_text from v$sql where sql_id='2b073tss4h1f3';
sql_id        executions parse_calls sql_text
------------- ---------- ----------- ------------------------------------------------------------
2b073tss4h1f3          2           2 select * from dept where deptno = :b

--//执行2次,分析2次.
--//如果采用statement caching
--//sesson 1:

set statementcache 100
variable c number = 10;
select * from dept where deptno = :c ;
select * from dept where deptno = :c ;
select sysdate from dual;
--//通过查询执行计划,确定sql_id='abzxwsyzmsu8h',另外打开会话:

--//sesson 2:
sys@book> select sql_id,executions,parse_calls,sql_text from v$sql where sql_id='abzxwsyzmsu8h';
sql_id        executions parse_calls sql_text
------------- ---------- ----------- ------------------------------------------------------------
abzxwsyzmsu8h          2           1 select * from dept where deptno = :c
--//执行2次,分析1次.

sys@book> @ sharepool/shp4 abzxwsyzmsu8h 0
text           kglhdadr         kglhdpar         c40                                        kglhdlmd   kglhdpmd   kglhdivc kglobhd0         kglobhd6           kglobhs0   kglobhs6   kglobt16   n0_6_16        n20   kglnahsh kglobt03        kglobt09
-------------- ---------------- ---------------- ---------------------------------------- ---------- ---------- ---------- ---------------- ---------------- ---------- ---------- ---------- --------- ---------- ---------- ------------- ----------
子游标句柄地址 000000007e344808 000000007e0f7020 select * from dept where deptno = :c              1          0          0 000000007e373578 000000007c5d06c8       8600      12144       3086     23830      23830 3208407312 abzxwsyzmsu8h          0
父游标句柄地址 000000007e0f7020 000000007e0f7020 select * from dept where deptno = :c              1          0          0 000000007e33c8a8 00                     4720          0          0      4720       4720 3208407312 abzxwsyzmsu8h      65535

--//kglhdlmd=1.session 1最后执行的是select sysdate from dual;

sys@book> select * from v$open_cursor where sql_id='abzxwsyzmsu8h';
saddr            sid user_name address          hash_value sql_id        sql_text                             last_sql_active_tim sql_exec_id cursor_type
---------------- --- --------- ---------------- ---------- ------------- ------------------------------------ ------------------- ----------- -----------
000000008631ddf0  41 scott     000000007e0f7020 3208407312 abzxwsyzmsu8h select * from dept where deptno = :c                                 open
--//可以发现光标状态已经是open,仅仅执行2次.

--//session 1:
scott@78> variable c number = 30;
scott@78> select * from dept where deptno = :c ;
    deptno dname          loc
---------- -------------- -------------
        30 sales          chicago

scott@book> select sql_id,executions,parse_calls,sql_text from v$sql where sql_id='abzxwsyzmsu8h';
sql_id        executions parse_calls sql_text
------------- ---------- ----------- ------------------------------------------------------------
abzxwsyzmsu8h          3           1 select * from dept where deptno = :c
--//执行3次,分析1次.

4.支持csv数据格式显示:
scott@78> set markup csv on
scott@78> select * from emp ;
"empno","ename","job","mgr","hiredate","sal","comm","deptno"
7369,"smith","clerk",7902,"1980-12-17 00:00:00",800,,20
7499,"allen","salesman",7698,"1981-02-20 00:00:00",1600,300,30
7521,"ward","salesman",7698,"1981-02-22 00:00:00",1250,500,30
7566,"jones","manager",7839,"1981-04-02 00:00:00",2975,,20
7654,"martin","salesman",7698,"1981-09-28 00:00:00",1250,1400,30
7698,"blake","manager",7839,"1981-05-01 00:00:00",2850,,30
7782,"clark","manager",7839,"1981-06-09 00:00:00",2450,,10
7788,"scott","analyst",7566,"1987-04-19 00:00:00",3000,,20
7839,"king","president",,"1981-11-17 00:00:00",5000,,10
7844,"turner","salesman",7698,"1981-09-08 00:00:00",1500,0,30
7876,"adams","clerk",7788,"1987-05-23 00:00:00",1100,,20
7900,"james","clerk",7698,"1981-12-03 00:00:00",950,,30
7902,"ford","analyst",7566,"1981-12-03 00:00:00",3000,,20
7934,"miller","clerk",7782,"1982-01-23 00:00:00",1300,,10
已选择 14 行。

--//ok.剩下的不在测试了,剩下大家自行测试.

set markup csv on delimiter '|'
select * from dept;

set markup csv on delimiter '|' quote off
select * from dept;

set markup csv off
select * from dept;

5.看来自己以前感觉错误,sqlplus的特性与oracle版本无关,你只要安装12cr2版本的client端,就可以使用新版本的sqlplus的特性.
  也说明一点,做事情不能评感觉,还是以测试为准,当然理论的理解也很重要.