在客户现场查看文档，照着命令敲，其实是很LOW的一件事，问题是很多时候，现场不允许带着你的笔记本和手机，你怎么办。很多常用的命令需要我们记住，随手捏来，每天花费半个小时边敲边理解是很好学习方式。
十载的西工网站建设经验，针对设计、前端、开发、售后、文案、推广等六对一服务，响应快，48小时及时工作处理。全网整合营销推广的优势是能够根据用户设备显示端的尺寸不同，自动调整西工建站的显示方式，使网站能够适用不同显示终端，在浏览器中调整网站的宽度，无论在任何一种浏览器上浏览网站，都能展现优雅布局与设计，从而大程度地提升浏览体验。创新互联建站从事“西工网站设计”,“西工网站推广”以来，每个客户项目都认真落实执行。
下面的诊断命令你能在理解的基础上盲敲下来么？？？
[root@11g-ocp ~]# date
Mon Dec 24 06:40:05 CST 2018
[root@11g-ocp ~]# su - oracle
<11g-ocp:orcl:/home/oracle>$sqlplus / as sysdba
SQL*Plus: Release 11.2.0.4.0 Production on Mon Dec 24 06:40:12 2018
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, Automatic Storage Management, OLAP and Real Application Testing options
SQL> select sysdate from dual;
SYSDATE
-----------------------
24-DEC-2018 06:40:18
SQL> oradebug setmypid;
Statement processed.
SQL> oradebug event 10046 trace name context forever,level 12;
Statement processed.
SQL> select count(*) from t;
COUNT(*)
----------
1
SQL> oradebug event 10046 trace name context off;
Statement processed.
SQL> oradebug tracefile_name;
/u01/app/oracle/diag/rdbms/orcl/orcl/trace/orcl_ora_2761.trc
SQL> !tkprof /u01/app/oracle/diag/rdbms/orcl/orcl/trace/orcl_ora_2761.trc ./1224.trc
TKPROF: Release 11.2.0.4.0 - Development on Mon Dec 24 06:41:30 2018
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
SQL> !more ./1224.trc
TKPROF: Release 11.2.0.4.0 - Development on Mon Dec 24 06:41:30 2018
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
Trace file: /u01/app/oracle/diag/rdbms/orcl/orcl/trace/orcl_ora_2761.trc
Sort options: default
********************************************************************************
count = number of times OCI procedure was executed
cpu = cpu time in seconds executing
elapsed = elapsed time in seconds executing
disk = number of physical reads of buffers from disk
query = number of buffers gotten for consistent read
current = number of buffers gotten in current mode (usually for update)
rows = number of rows processed by the fetch or execute call
********************************************************************************
SQL ID: cyzznbykb509s Plan Hash: 2966233522
select count(*)
from
t
call count cpu elapsed disk query current rows
------- ------ -------- ---------- ---------- ---------- ---------- ----------
Parse 1 0.00 0.00 0 0 0 0
Execute 1 0.00 0.00 0 0 0 0
Fetch 2 0.00 0.00 0 2 0 1
------- ------ -------- ---------- ---------- ---------- ---------- ----------
total 4 0.00 0.00 0 2 0 1
Misses in library cache during parse: 0
Optimizer mode: ALL_ROWS
Parsing user id: SYS
Number of plan statistics captured: 1
Rows (1st) Rows (avg) Rows (max) Row Source Operation
---------- ---------- ---------- ---------------------------------------------------
1 1 1 SORT AGGREGATE (cr=2 pr=0 pw=0 time=65 us)
1 1 1 TABLE ACCESS FULL T (cr=2 pr=0 pw=0 time=37 us cost=2 size=0 card=1)
Elapsed times include waiting on following events:
Event waited on Times Max. Wait Total Waited
---------------------------------------- Waited ---------- ------------
SQL*Net message to client 2 0.00 0.00
SQL*Net message from client 2 10.31 10.31
********************************************************************************
OVERALL TOTALS FOR ALL NON-RECURSIVE STATEMENTS
call count cpu elapsed disk query current rows
------- ------ -------- ---------- ---------- ---------- ---------- ----------
Parse 1 0.00 0.00 0 0 0 0
Execute 1 0.00 0.00 0 0 0 0
Fetch 2 0.00 0.00 0 2 0 1
------- ------ -------- ---------- ---------- ---------- ---------- ----------
total 4 0.00 0.00 0 2 0 1
Misses in library cache during parse: 0
Elapsed times include waiting on following events:
Event waited on Times Max. Wait Total Waited
---------------------------------------- Waited ---------- ------------
SQL*Net message to client 3 0.00 0.00
SQL*Net message from client 3 10.31 15.89
OVERALL TOTALS FOR ALL RECURSIVE STATEMENTS
call count cpu elapsed disk query current rows
------- ------ -------- ---------- ---------- ---------- ---------- ----------
Parse 0 0.00 0.00 0 0 0 0
Execute 0 0.00 0.00 0 0 0 0
Fetch 0 0.00 0.00 0 0 0 0
------- ------ -------- ---------- ---------- ---------- ---------- ----------
total 0 0.00 0.00 0 0 0 0
Misses in library cache during parse: 0
1 user SQL statements in session.
0 internal SQL statements in session.
1 SQL statements in session.
********************************************************************************
Trace file: /u01/app/oracle/diag/rdbms/orcl/orcl/trace/orcl_ora_2761.trc
Trace file compatibility: 11.1.0.7
Sort options: default
1 session in tracefile.
1 user SQL statements in trace file.
0 internal SQL statements in trace file.
1 SQL statements in trace file.
1 unique SQL statements in trace file.
62 lines in trace file.
0 elapsed seconds in trace file.
SQL>