Lock by DBLink – How to locate the remote session?

And if you identify a lock or other unwanted operation by a DBLink session, how to identify the original session in remote database (origin dabatase)?
The one million answer is simple: by process of v$session. By the way, looks like is easier than find the local process (spid)… Take a look in my example (scripts in the end of post):

dest> @sid
Sid:10035
Inst:1
SEQ# EVENT MODULE STATUS SID SERIAL# INST_ID
----- --------- ---------- ---------- ---------- ---------- ----------
29912 SQL*Net message from client oracle@origin2(TNS V1-V3) INACTIVE 10035 35 1
dest> @spid
SPID SID PID PROCESS_FOR_DB_LINK MACHINE LOGON_TIME
------ ---------- ---------- ----------- ----------- -----------
16188960 10035 882 17302472 origin2 24/08/2015 07:43:40

Now I know the sid 10035 refers to local process 16188960 and the process on origin database is 17302472. What I do what I want if this process:

root@origin2:/oracle/diag/rdbms/origin/origin2/trace>ps -ef |grep 17302472
grid 17302472 1 97 07:42:42 - 5:58 oracleorigin2 (LOCAL=NO)
root 24445782 36700580 0 08:05:45 pts/3 0:00 grep 17302472

What include to locae the session in the database by spid, see the sql, and etecetera:

origin> @spid2
Enter value for process: 17302472
SID SERIAL# USERNAME OSUSER PROGRAM STATUS
------- ---------- ----------- ----------- --------------- ----------
7951 41323 USER_XPTO scheduler_user sqlplus@scheduler_app.domain.net (TNS V1-V3) ACTIVE
database2> @sid
Sid:7951
Inst: 2
SQL_ID SEQ# EVENT MODULE STATUS SID SERIAL# INST_ID
---------- ----- --------- ------- --------- ----- ------ ----------
1w1wz2mdunya1 56778 db file sequential read REMOTE_LOAD ACTIVE 7951 41323 2

That’s OK?
Simple isn’t?

The used Scripts (except the “sid”, that is a simple SQL on gv$session):

Get SPID and PROCESS FOR DBLINK from a SID:

# spid:
col machine format a30
col process format 999999
select p.spid,b.sid, p.pid, b.process as process_for_db_link, machine, logon_time
from v$session b, v$process p
where b.paddr=p.addr
and sid=&sid
/

Get SID from SPID:

#spid2:
SELECT s.sid, s.serial#, s.username,
s.osuser, s.program, s.status,
FROM v$session s, v$process p
WHERE s.paddr = p.addr
AND p.spid IN (&process);
/

See ya!
Matheus.

Advertisements

Sqlplus: Connect without configure TNSNAMES

Okey, you must to know, but is always useful to remmember that… If you don’t want to configure your TNSNAMES, you can connect directly to description of your database. This way:

sqlplus> conn matheus_boesing@(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=mydb.domain.net)(PORT=1531)))(CONNECT_DATA=(service_name=mydb)))
Enter password: ********
Connected.
sqlplus>

Based on this, I made two scripts, to connect with the sid (c.sql) or with the service_name (s.sql) and make my life easier. Here the scripts:

sqlplus>get c
1 DEFINE VHOST = &1.
2 DEFINE VPORT = &2.
3 DEFINE VSID = &3.
4 DEFINE VDESC='(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=&VHOST)(PORT=&VPORT)))(CONNECT_DATA=(SID=&VSID)(server=dedicated)))'
5 disconnect
6 connect matheus_boesing@&&VDESC
7 set linesize 1000
8 set sqlprom '&&VSID> '
9 select instance_name, host_name
10 from v$instance;
11 exec dbms_application_info.SET_MODULE('MATHEUS_BOESING','DBA');
12 alter session set nls_date_format='DD/MM/YYYY HH24:MI:SS';
13 UNDEFINE VDESC
14 UNDEFINE 1
15 UNDEFINE 2
16* UNDEFINE 3
sqlplus>get s
1 DEFINE VHOST = &1.
2 DEFINE VPORT = &2.
3 DEFINE VSID = &3.
4 DEFINE VDESC='(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=&VHOST)(PORT=&VPORT)))(CONNECT_DATA=(SERVICE_NAME=&VSID)(server=dedicated)))'
5 prompt &VDESC
6 disconnect
7 connect matheus_boesing@&&VDESC
8 set linesize 1000
9 set sqlprom '&&VSID> '
10 select instance_name, host_name
11 from v$instance;
12 exec dbms_application_info.SET_MODULE('MATHEUS_BOESING','DBA');
13 alter session set nls_date_format='DD/MM/YYYY HH24:MI:SS';
14 UNDEFINE VDESC
15 UNDEFINE 1
16 UNDEFINE 2
17* UNDEFINE 3
sqlplus>

It can be used like this:

sqlplus>@s mydb.domain.net 1531 mydb
(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=mydb.domain.net)(PORT=1531)))(CONNECT_DATA=(SERVICE_NAME=mydb)(server=dedicated)))
Enter password: ********
Connected.

Ok, but, let’s suppose you are working in a cluster and wants to connect directly to the another instance. I made the script below (ci.sql). It’s not beautiful, but is a lot hopeful:

sqlplus> get ci
1 DEFINE VINT = &1.
2 undefine VHOST
3 undefine VSID
4 VARIABLE VCONN varchar2(100)
5 PRINT ret_val
6 BEGIN
7 SELECT '@c '||host_name||' 1521 '||INSTANCE_NAME
8 INTO :VCONN
9 FROM gv$instance where INSTANCE_NUMBER=&VINT;
10 END;
11 /
12 set head off;
13 spool auxcon.sql
14 prompt set head on;
15 print :VCONN
16 prompt set head on;
17 spool off;
18* @auxcon
sqlplus>

As you see, you inform the inst_id you want to connect. It can be used like:

mydb> @instance
INSTANCE_NAME
------------------------------
mydb_2
mydb> @instances
INST_NUMBER INST_NAME
----------- ---------------------------------------
1 db2srvr2p.sicredi.net:mydb_1
2 db1srvr1p.sicredi.net:mydb_2
mydb> @ci 1
@c db2srvr2p.sicredi.net 1521 mydb_1
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,
Data Mining and Real Application Testing options
Enter password: ********
Connected.
mydb_1> @instance
INSTANCE_NAME
------------------------------
mydb_1

That’s right?
The scripts a shared help me a lot every day, and it’s exclusive.
I not founded nothing like this. So, I made. 🙂

Matheus.

ASM: Disk Imbalance Query

It can be useful if you work frequently with OEM metrics…

# OEM Query

SELECT file_num, MAX(extent_count) max_disk_extents, MIN(extent_count)
min_disk_extents
, MAX(extent_count) - MIN(extent_count) disk_extents_imbalance
FROM (SELECT number_kffxp file_num, disk_kffxp disk_num, COUNT(xnum_kffxp)
extent_count
FROM x$kffxp
WHERE group_kffxp = 1
AND disk_kffxp != 65534
GROUP BY number_kffxp, disk_kffxp
ORDER BY number_kffxp, disk_kffxp)
GROUP BY file_num
HAVING MAX(extent_count) - MIN(extent_count) > 5
ORDER BY disk_extents_imbalance DESC;

# MatheusDBA Query

select max(free_mb) biggest, min(free_mb) lowest, avg(free_mb) AVG,
trunc(GREATEST ((avg(free_mb)*100/max(free_mb)),(min(free_mb)*100/avg(free_mb))),2)||'%' as balanced,
trunc(100-(GREATEST ((avg(free_mb)*100/max(free_mb)),(min(free_mb)*100/avg(free_mb)))),2)||'%' as inbalanced
from v$asm_disk
where group_number in
(select group_number from v$asm_diskgroup where name = upper('&DG'));

I made my own query for two reasons:
1) I didn’t have the OEM query in the time i made it.
2) My query measures the inbalance with the avg of the disks (if everydisk would balanced, how would be the difference), rather than the real/present difference between the disk with the maximum and the minimum usage…

So, you can chose the one you need… 🙂

Matheus.

Oracle Convert Number into Days, Hours, Minutes

There’s a little trick…
Today I had to convert a “number” of minutes into hours:minutes format. Something like convert 570 minutes in format hour:minutes. As you know, 570/60 is “9,5” and should be “9:30”.

Lets use 86399 seconds (23:59:59) as example:

I began testing “to_char(to_date)” functions:
boesing@db>select to_char(to_date(86399,'sssss'),'hh24:mi:ss') formated from dual;

FORMATED
——–
23:59:59

Ok, it works. But using “seconds past midnight” (sssss). By the way, it works between 0 and 86399 only:

boesing@db> select to_char(to_date(86400,'sssss'),'hh24:mi:ss') from dual;
select to_char(to_date(86400,'sssss'),'hh24:mi:ss') from dual
*
ERROR at line 1:
ORA-01853: seconds in day must be between 0 and 86399

The problem remains. How to use minutes in 3 digits (570 minutes -> 9:30), for example?
The best way I solve was:

--- Seconds in hours:minutes:seconds
--- If you comment the first "TO_CHAR" line, can be minutes in hours:minutes too..
select
TO_CHAR(TRUNC(vlr/3600),'FM9900') || ':' || -- hours
TO_CHAR(TRUNC(MOD(vlr,3600)/60),'FM00') || ':' || -- minutes
TO_CHAR(MOD(vlr,60),'FM00') -- second
from dual;

It always works. 🙂

boesing@db>select
2 TO_CHAR(TRUNC(86399/3600),'FM9900') || ':' || -- hours
3 TO_CHAR(TRUNC(MOD(86399,3600)/60),'FM00') || ':' || -- minutes
4 TO_CHAR(MOD(86399,60),'FM00') -- second
5 from dual;

TO_CHAR(TRUNC
————-
23:59:59

boesing@db>select
2 TO_CHAR(TRUNC(570/3600),’FM9900′) || ‘:’ || — hours
3 TO_CHAR(TRUNC(MOD(570,3600)/60),’FM00′) || ‘:’ || — minutes
4 TO_CHAR(MOD(570,60),’FM00′) — second
5 from dual;

TO_CHAR(TRUNC
————-
00:09:30

boesing@db>select
2 TO_CHAR(TRUNC(MOD(570,3600)/60),’FM00′) || ‘:’ || — hours
3 TO_CHAR(MOD(570,60),’FM00′) — minutes
4 from dual;

TO_CHAR
——-
09:30

Any better way? Leave a comment. Thanks!

Matheus.