I am not going to post how to convert to extended data type since there are many blogs on that already.
Just a reminder, there’s no going back; hence have backup and possibly minimize changes during testing to be able to restore (which is ideal and may not be feasible).
Before reverting to MAX_STRING_SIZE=STANDARD, columns affected by extended data type need to be identified.
From Oracle documentation, MAX_STRING_SIZE controls the maximum size of VARCHAR2, NVARCHAR2, (more...)
Recently, there has been discussion about using rlwrap for Goldengate on Twitter feed.
Truthfully, I did not know there was RPM for this and I did not even know it was already installed.
It just worked, when I had set it up.
A very nice cheat sheet for using yum.
Yum Command Cheat Sheet for Red Hat Enterprise Linux
I started to investigate how was rlwrap installed on the system.
$ cat /etc/issue
I was working on configuring multiple local listeners and having difficulties setting local_listener using full address list.
How would you set up local_listeners?
There are 4 listeners, 1-4.
$ lsnrctl status listener1
LSNRCTL for Linux: Version 18.104.22.168.0 - Production on 17-AUG-2016 21:34:31
Copyright (c) 1991, 2013, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1551)))
STATUS of the LISTENER
Version TNSLSNR for Linux: Version 22.214.171.124.0 (more...)
Due to security hardening, telnet is not available.
$ rpm -q --whatprovides nc
$ yum list nc
Loaded plugins: refresh-packagekit, security
epel/metalink | 11 kB 00:00
epel | 4.3 kB 00:00
epel/primary_db | 5.9 MB 00:03
public_ol6_UEKR3_latest | 1.2 kB 00:00
public_ol6_latest | 1.4 kB 00:00
nc.x86_64 1.84-24.el6 @public_ol6_latest
$ nc -v -z -w 3 stackoverflow.com 80; echo $?
Connection to stackoverflow.com 80 port [tcp/http] succeeded!
Session 1 starts UPDATE and nothing else.
02:53:39 ARROW:(MDINH@leo):PRIMARY> update t set object_id=100;
1 row updated.
02:53:50 ARROW:(SYSTEM@leo):PRIMARY> update mdinh.t set object_id=2;
02:53:58 ARROW:(DEMO@leo):PRIMARY> update mdinh.t set object_id=200;
Monitor blocking locks
$ sysdba @b.sql
SQL*Plus: Release 126.96.36.199.0 Production on Sat Aug 6 02:55:03 2016
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Oracle Database (more...)
Confession: I have not been using OEM for decades since there was never a real need for it and it’s starting to take its toll on me.
Throughout the day, I keep getting paged from OEM – Message=Number of failed login attempts exceeds threshold value.
The information provided is utterly useless, e.g. what is the threshold value and what’s the error code.
What would be useful is to provide the SQL used for the (more...)
I don’t know but best to have one.
With multi-tenant database, I would use OMF to keep it simple and to avoid having to remember about FILE_NAME_CONVERT.
When creating PDB, there may be specification for ADMIN USER as show below:
CREATE PLUGGABLE DATABASE april ADMIN USER april_admin IDENTIFIED BY oracle;
Here are some examples I have come across (Names and Blogs are not provided to protect the innocents):
create pluggable database PDB1 admin user pdb1_admin
There was an incident where /u01 was lost.
This means having to reinstall and patch software again.
When installing grid and I encountered:
CRS is already configured on this node for crshome=/u01/app/oracle/product/11.2.0/grid
Ah Crap! This is me being melodramatic.
The system was using Oracle Restart, it needs to be removed.
# /u01/app/oracle/product/11.2.0/grid/crs/install/roothas.pl -deconfig -force -verbose
In hindsight, it would have been much easier to delete from /etc/oracle.
Guess what? ASM will (more...)
The following ASM disks were created which does not follow convention:
ASM_REDO01_006, ASM_REDO01_007, ASM_REDO01_008, ASM_REDO01_009, and ASM_REDO01_010
It should be:
ASM_REDO01_001, ASM_REDO01_002, ASM_REDO01_003, ASM_REDO01_004, and ASM_REDO01_005
Hence, we will need to recreate them. Here’s the process for me to remember.
conn / as sysasm
drop diskgroup DATA01;
drop diskgroup REDO01;
SQL> show parameter disk
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
asm_diskstring string ORCL:*
# /etc/init.d/oracleasm querydisk -d ASM_DATA01_001
Disk "ASM_DATA01_001" is (more...)
1.8 Details of Support for Objects and Operations in Oracle DDL
The following tables are excluded by default.
"*.AQ$*", // advanced queues
"*.DR$*$*", // oracle text
"*.M*_*$$", // Spatial index
"*.MLOG$*", // materialized views
"*.OGG$*", // AQ OGG queue table
"*.ET$*", // Data Pump external tables
"*.RUPD$*", // materialized views
"*.SYS_C*", // constraints
"*.MDR*_*$", // Spatial Sequence and Table