Stop Migrating Databases to 12c!

If you are starting an upgrade plan, do it directly to 19c. Why?

Well, first let’s say that 19c is “equal” to 12.2.0.3 on previous version model, while 18c is 12.2.0.2, after latest 12.2.0.1. So, thinking reasonably, you would already plan for latest PSU on the future version, right? So this is 19c.

But not only this. It’s well known that Oracle’s Terminal Patchset is the Long Term Release for each version. And for 12.2 family this is 19c.

The image below (From Doc ID 742060.1) should help on clarifying this:

versions

In summary, since August 1st 2019:
– 11.2.0.4 is already on Extended Support (20% more expensive unless you have ULA)
– 12.1 family is already on Extended Support (20% more expensive unless you have ULA)

Which only leave us with 12.2 Family. Now I ask you, why jump to any “PSU” other than the final one?
Also, support on 12.2.0.1 goes only up to Nov 2020 and for 18c (12.2.0.2) only to Jun 2021, while 19c goes up to 2026 with ES/ULA!

I’m not even raising the great improvements we have on newer versions (if you are in 11.2, shame on you, you are basically 6 years behind the world technology wise).
Myself , I already migrated several databases on different clients to 19c and it’s running preeeetty fine. So trust on it!

Ok, so to migrate to 19c? (Some tips):
– To migrate directly to 19c you need to be on supported terminal patch set (11.2.0.4, 12.1.0.2) or on 12.2 family (12.2.0.1, 18c).
– Get in touch and use AutoUpgrade mechanism (you’ll love it!) – AutoUpgrade Tool (Doc ID 2485457.1)
– Check Upgrade Guide: https://docs.oracle.com/en/database/oracle/oracle-database/19/upgrd/index.html
– Have a look on Mike Dietrich blog for news: https://mikedietrichde.com/
– Test it before doing in prod.

Additional Reference:
Release Schedule of Current Database Releases (Doc ID 742060.1)
Very nice and complete post (in portuguese) on this topic from Ricardo Portilho.

I like very much the table below as well:

NewScreenshot 2019-08-13 às 15.11.34

See you!

Invalid system views after upgrading from 12c to 18c – X_$KGLOB and X_$KGLCURSOR

I was working on a client upgrade from 12c to 18c. The upgrade was done manually. After the dbupgrade 2 system views got invalid, X_$KGLCURSOR and X_$KGLOB

OWNER OBJECT_NAME OBJECT_TYPE STATUS
------------ -------------------------------------------------- ---------------------------------------- -------
SYS X_$KGLOB VIEW INVALID
SYS X_$KGLCURSOR VIEW INVALID

Man system objects invalid after an upgrade is never good.

Troubleshooting, I got the view text and tried to execute its sql

SQL> select TEXT from dba_Views where view_name = 'X_$KGLOB';

TEXT
------------------------------------------------------------------------------------------------------------------------------------------------------
SELECT "ADDR","INDX","INST_ID","CON_ID","KGLHDADR","KGLHDPAR","KGLHDCLT","KGLNAOWN","KGLNAOBJ","KGLFNOBJ","KGLNADLK","KGLNAHSH","KGLNAHSV","KGLNATIM",
"KGLNAPTM","KGLHDNSP","KGLHDNSD","KGLHDLMD","KGLHDPMD","KGLHDFLG","KGLHDOBJ","KGLHDLDC","KGLHDIVC","KGLHDEXC","KGLHDLKC","KGLHDKMK","KGLHDDMK","KGLHDA
MK","KGLOBFLG","KGLOBSTA","KGLOBTYP","KGLOBTYD","KGLOBHMK","KGLOBHS0","KGLOBHS1","KGLOBHS2","KGLOBHS3","KGLOBHS4","KGLOBHS5","KGLOBHS6","KGLOBHS7","KG
LOBHD0","KGLOBHD1","KGLOBHD2","KGLOBHD3","KGLOBHD4","KGLOBHD5","KGLOBHD6","KGLOBHD7","KGLOBPC0","KGLOBPC6","KGLOBTP0","KGLOBT00","KGLOBT01","KGLOBT02"
,"KGLOBT03","KGLOBT04","KGLOBT05","KGLOBT35","KGLOBT06","KGLOBT07","KGLOBT08","KGLOBT09","KGLOBT10","KGLOBT11","KGLOBT12","KGLOBT13","KGLOBT14","KGLOB
T15","KGLOBT16","KGLOBT17","KGLOBT18","KGLOBT19","KGLOBT20","KGLOBT21","KGLOBT22","KGLOBT23","KGLOBT24","KGLOBT25","KGLOBT26","KGLOBT28","KGLOBT29","K
GLOBT30","KGLOBT31","KGLOBT27","KGLOBT32","KGLOBT33","KGLOBWAP","KGLOBWCC","KGLOBWCL","KGLOBWUI","KGLOBWDW","KGLOBT42","KGLOBT43","KGLOBT44","KGLOBT45
","KGLOBT46","KGLOBT47","KGLOBT49","KGLOBT50","KGLOBT52","KGLOBT53","KGLOBTL0","KGLOBTL1","KGLOBTS0","KGLOBTS1","KGLOBTN0","KGLOBTN1","KGLOBTN2","KGLO
BTN3","KGLOBTN4","KGLOBTN5","KGLOBTS2","KGLOBTS3","KGLOBTS5","KGLOBTT0","KGLOBCCE","KGLOBCCEH","KGLOBCLA","KGLOBCLC","KGLOBCCC","KGLOBTS4","KGLOBCBCA"
,"KGLOBT48","KGLOBDSO","KGLOBDEX","KGLOBDPX","KGLOBDLD","KGLOBDIV","KGLOBDPS","KGLOBDDR","KGLOBDDW","KGLOBDBF","KGLOBDRO","KGLOBDCP","KGLOBDEL","KGLOB
DFT","KGLOBDEF","KGLOBDUI","KGLOBDCL","KGLOBDAP","KGLOBDCC","KGLOBDPL","KGLOBDJV","KGLOBACS","KGLOBTS6","KGLOBTS7","KGLOBT54","KGLOBT55","KGLOBT56","K
GLOBT57","KGLOBDCO","KGLOBDCI","KGLOBDRR","KGLOBDRB","KGLOBDWR","KGLOBDWB","KGLOBT58","KGLOBDOR","KGLHDMTX","KGLHDMVL","KGLHDMSP","KGLHDMGT","KGLHDDMT
X","KGLHDDVL","KGLHDDSP","KGLHDDGT","KGLHDBID","KGLHDBMTX","KGLHDBVL","KGLHDBSP","KGLHDBGT","KGLOBT59","KGLOBDCU","KGLOBPROP","KGLNACON","KGLNAO1N","K
GLHDMAR","KGLMPFLG","KGLOBAQP","KGLOBT60","KGLOBT61","KGLIMSCANS","KGLIMBYTESUNCOMP","KGLIMBYTESINMEM" FROM X$KGLOB


1 row selected.
SQL> SELECT "ADDR","INDX","INST_ID","CON_ID","KGLHDADR","KGLHDPAR","KGLHDCLT","KGLNAOWN","KGLNAOBJ","KGLFNOBJ","KGLNADLK","KGLNAHSH","KGLNAHSV","KGLNATIM","KGLNAPTM","KGLHDNSP","KGLHDNSD","KGLHDLMD","KGLHDPMD","KGLHDFLG","KGLHDOBJ","KGLHDLDC","KGLHDIVC","KGLHDEXC","KGLHDLKC","KGLHDKMK","KGLHDDMK","KGLHDAMK","KGLOBFLG","KGLOBSTA","KGLOBTYP","KGLOBTYD","KGLOBHMK","KGLOBHS0","KGLOBHS1","KGLOBHS2","KGLOBHS3","KGLOBHS4","KGLOBHS5","KGLOBHS6","KGLOBHS7","KGLOBHD0","KGLOBHD1","KGLOBHD2","KGLOBHD3","KGLOBHD4","KGLOBHD5","KGLOBHD6","KGLOBHD7","KGLOBPC0","KGLOBPC6","KGLOBTP0","KGLOBT00","KGLOBT01","KGLOBT02","KGLOBT03","KGLOBT04","KGLOBT05","KGLOBT35","KGLOBT06","KGLOBT07","KGLOBT08","KGLOBT09","KGLOBT10","KGLOBT11","KGLOBT12","KGLOBT13","KGLOBT14","KGLOBT15","KGLOBT16","KGLOBT17","KGLOBT18","KGLOBT19","KGLOBT20","KGLOBT21","KGLOBT22","KGLOBT23","KGLOBT24","KGLOBT25","KGLOBT26","KGLOBT28","KGLOBT29","KGLOBT30","KGLOBT31","KGLOBT27","KGLOBT32","KGLOBT33","KGLOBWAP","KGLOBWCC","KGLOBWCL","KGLOBWUI","KGLOBWDW","KGLOBT42","KGLOBT43","KGLOBT44","KGLOBT45","KGLOBT46","KGLOBT47","KGLOBT49","KGLOBT50","KGLOBT52","KGLOBT53","KGLOBTL0","KGLOBTL1","KGLOBTS0","KGLOBTS1","KGLOBTN0","KGLOBTN1","KGLOBTN2","KGLOBTN3","KGLOBTN4","KGLOBTN5","KGLOBTS2","KGLOBTS3","KGLOBTS5","KGLOBTT0","KGLOBCCE","KGLOBCCEH","KGLOBCLA","KGLOBCLC","KGLOBCCC","KGLOBTS4","KGLOBCBCA","KGLOBT48","KGLOBDSO","KGLOBDEX","KGLOBDPX","KGLOBDLD","KGLOBDIV","KGLOBDPS","KGLOBDDR","KGLOBDDW","KGLOBDBF","KGLOBDRO","KGLOBDCP","KGLOBDEL","KGLOBDFT","KGLOBDEF","KGLOBDUI","KGLOBDCL","KGLOBDAP","KGLOBDCC","KGLOBDPL","KGLOBDJV","KGLOBACS","KGLOBTS6","KGLOBTS7","KGLOBT54","KGLOBT55","KGLOBT56","KGLOBT57","KGLOBDCO","KGLOBDCI","KGLOBDRR","KGLOBDRB","KGLOBDWR","KGLOBDWB","KGLOBT58","KGLOBDOR","KGLHDMTX","KGLHDMVL","KGLHDMSP","KGLHDMGT","KGLHDDMTX","KGLHDDVL","KGLHDDSP","KGLHDDGT","KGLHDBID","KGLHDBMTX","KGLHDBVL","KGLHDBSP","KGLHDBGT","KGLOBT59","KGLOBDCU","KGLOBPROP","KGLNACON","KGLNAO1N","KGLHDMAR","KGLMPFLG","KGLOBAQP","KGLOBT60","KGLOBT61","KGLIMSCANS","KGLIMBYTESUNCOMP","KGLIMBYTESINMEM" FROM X$KGLOB;
SELECT "ADDR","INDX","INST_ID","CON_ID","KGLHDADR","KGLHDPAR","KGLHDCLT","KGLNAOWN","KGLNAOBJ","KGLFNOBJ","KGLNADLK","KGLNAHSH","KGLNAHSV","KGLNATIM","KGLNAPTM","KGLHDNSP","KGLHDNSD","KGLHDLMD","KGLHDPMD","KGLHDFLG","KGLHDOBJ","KGLHDLDC","KGLHDIVC","KGLHDEXC","KGLHDLKC","KGLHDKMK","KGLHDDMK","KGLHDAMK","KGLOBFLG","KGLOBSTA","KGLOBTYP","KGLOBTYD","KGLOBHMK","KGLOBHS0","KGLOBHS1","KGLOBHS2","KGLOBHS3","KGLOBHS4","KGLOBHS5","KGLOBHS6","KGLOBHS7","KGLOBHD0","KGLOBHD1","KGLOBHD2","KGLOBHD3","KGLOBHD4","KGLOBHD5","KGLOBHD6","KGLOBHD7","KGLOBPC0","KGLOBPC6","KGLOBTP0","KGLOBT00","KGLOBT01","KGLOBT02","KGLOBT03","KGLOBT04","KGLOBT05","KGLOBT35","KGLOBT06","KGLOBT07","KGLOBT08","KGLOBT09","KGLOBT10","KGLOBT11","KGLOBT12","KGLOBT13","KGLOBT14","KGLOBT15","KGLOBT16","KGLOBT17","KGLOBT18","KGLOBT19","KGLOBT20","KGLOBT21","KGLOBT22","KGLOBT23","KGLOBT24","KGLOBT25","KGLOBT26","KGLOBT28","KGLOBT29","KGLOBT30","KGLOBT31","KGLOBT27","KGLOBT32","KGLOBT33","KGLOBWAP","KGLOBWCC","KGLOBWCL","KGLOBWUI","KGLOBWDW","KGLOBT42","KGLOBT43","KGLOBT44","KGLOBT45","KGLOBT46","KGLOBT47","KGLOBT49","KGLOBT50","KGLOBT52","KGLOBT53","KGLOBTL0","KGLOBTL1","KGLOBTS0","KGLOBTS1","KGLOBTN0","KGLOBTN1","KGLOBTN2","KGLOBTN3","KGLOBTN4","KGLOBTN5","KGLOBTS2","KGLOBTS3","KGLOBTS5","KGLOBTT0","KGLOBCCE","KGLOBCCEH","KGLOBCLA","KGLOBCLC","KGLOBCCC","KGLOBTS4","KGLOBCBCA","KGLOBT48","KGLOBDSO","KGLOBDEX","KGLOBDPX","KGLOBDLD","KGLOBDIV","KGLOBDPS","KGLOBDDR","KGLOBDDW","KGLOBDBF","KGLOBDRO","KGLOBDCP","KGLOBDEL","KGLOBDFT","KGLOBDEF","KGLOBDUI","KGLOBDCL","KGLOBDAP","KGLOBDCC","KGLOBDPL","KGLOBDJV","KGLOBACS","KGLOBTS6","KGLOBTS7","KGLOBT54","KGLOBT55","KGLOBT56","KGLOBT57","KGLOBDCO","KGLOBDCI","KGLOBDRR","KGLOBDRB","KGLOBDWR","KGLOBDWB","KGLOBT58","KGLOBDOR","KGLHDMTX","KGLHDMVL","KGLHDMSP","KGLHDMGT","KGLHDDMTX","KGLHDDVL","KGLHDDSP","KGLHDDGT","KGLHDBID","KGLHDBMTX","KGLHDBVL","KGLHDBSP","KGLHDBGT","KGLOBT59","KGLOBDCU","KGLOBPROP","KGLNACON","KGLNAO1N","KGLHDMAR","KGLMPFLG","KGLOBAQP","KGLOBT60","KGLOBT61","KGLIMSCANS","KGLIMBYTESUNCOMP","KGLIMBYTESINMEM" FROM X$KGLOB
*
ERROR at line 1:
ORA-00904: "KGLOBT24": invalid identifier
SQL> select TEXT from dba_Views where view_name = 'X_$KGLCURSOR'

TEXT
------------------------------------------------------------------------------------------------------------------------------------------------------
SELECT "ADDR","INDX","INST_ID","CON_ID","KGLHDADR","KGLHDPAR","KGLHDCLT","KGLNAOWN","KGLNAOBJ","KGLFNOBJ","KGLNADLK","KGLNAHSH","KGLNAHSV","KGLNATIM",
"KGLNAPTM","KGLHDNSP","KGLHDNSD","KGLHDLMD","KGLHDPMD","KGLHDFLG","KGLHDOBJ","KGLHDLDC","KGLHDIVC","KGLHDEXC","KGLHDLKC","KGLHDKMK","KGLHDDMK","KGLHDA
MK","KGLOBFLG","KGLOBSTA","KGLOBTYP","KGLOBTYD","KGLOBHMK","KGLOBHS0","KGLOBHS1","KGLOBHS2","KGLOBHS3","KGLOBHS4","KGLOBHS5","KGLOBHS6","KGLOBHS7","KG
LOBHD0","KGLOBHD1","KGLOBHD2","KGLOBHD3","KGLOBHD4","KGLOBHD5","KGLOBHD6","KGLOBHD7","KGLOBPC0","KGLOBPC6","KGLOBTP0","KGLOBT00","KGLOBT01","KGLOBT02"
,"KGLOBT03","KGLOBT04","KGLOBT05","KGLOBT35","KGLOBT06","KGLOBT07","KGLOBT08","KGLOBT09","KGLOBT10","KGLOBT11","KGLOBT12","KGLOBT13","KGLOBT14","KGLOB
T15","KGLOBT16","KGLOBT17","KGLOBT18","KGLOBT19","KGLOBT20","KGLOBT21","KGLOBT22","KGLOBT23","KGLOBT24","KGLOBT25","KGLOBT26","KGLOBT28","KGLOBT29","K
GLOBT30","KGLOBT31","KGLOBT27","KGLOBT32","KGLOBT33","KGLOBWAP","KGLOBWCC","KGLOBWCL","KGLOBWUI","KGLOBWDW","KGLOBT42","KGLOBT43","KGLOBT44","KGLOBT45
","KGLOBT46","KGLOBT47","KGLOBT49","KGLOBT50","KGLOBT52","KGLOBT53","KGLOBTL0","KGLOBTL1","KGLOBTS0","KGLOBTS1","KGLOBTN0","KGLOBTN1","KGLOBTN2","KGLO
BTN3","KGLOBTN4","KGLOBTN5","KGLOBTS2","KGLOBTS3","KGLOBTS5","KGLOBTT0","KGLOBCCE","KGLOBCCEH","KGLOBCLA","KGLOBCLC","KGLOBCCC","KGLOBTS4","KGLOBCBCA"
,"KGLOBT48","KGLOBDSO","KGLOBDEX","KGLOBDPX","KGLOBDLD","KGLOBDIV","KGLOBDPS","KGLOBDDR","KGLOBDDW","KGLOBDBF","KGLOBDRO","KGLOBDCP","KGLOBDEL","KGLOB
DFT","KGLOBDEF","KGLOBDUI","KGLOBDCL","KGLOBDAP","KGLOBDCC","KGLOBDPL","KGLOBDJV","KGLOBACS","KGLOBTS6","KGLOBTS7","KGLOBT54","KGLOBT55","KGLOBT56","K
GLOBT57","KGLOBDCO","KGLOBDCI","KGLOBDRR","KGLOBDRB","KGLOBDWR","KGLOBDWB","KGLOBT58","KGLOBDOR","KGLHDMTX","KGLHDMVL","KGLHDMSP","KGLHDMGT","KGLHDDMT
X","KGLHDDVL","KGLHDDSP","KGLHDDGT","KGLHDBID","KGLHDBMTX","KGLHDBVL","KGLHDBSP","KGLHDBGT","KGLOBT59","KGLOBDCU","KGLOBPROP","KGLNACON","KGLNAO1N","K
GLHDMAR","KGLMPFLG","KGLOBAQP","KGLOBT60","KGLOBT61","KGLIMSCANS","KGLIMBYTESUNCOMP","KGLIMBYTESINMEM" FROM X$KGLCURSOR


1 row selected.
SQL> SELECT "ADDR","INDX","INST_ID","CON_ID","KGLHDADR","KGLHDPAR","KGLHDCLT","KGLNAOWN","KGLNAOBJ","KGLFNOBJ","KGLNADLK","KGLNAHSH","KGLNAHSV","KGLNATIM",
"KGLNAPTM","KGLHDNSP","KGLHDNSD","KGLHDLMD","KGLHDPMD","KGLHDFLG","KGLHDOBJ","KGLHDLDC","KGLHDIVC","KGLHDEXC","KGLHDLKC","KGLHDKMK","KGLHDDMK","KGLHDA
MK","KGLOBFLG","KGLOBSTA","KGLOBTYP","KGLOBTYD","KGLOBHMK","KGLOBHS0","KGLOBHS1","KGLOBHS2","KGLOBHS3","KGLOBHS4","KGLOBHS5","KGLOBHS6","KGLOBHS7","KG
LOBHD0","KGLOBHD1","KGLOBHD2","KGLOBHD3","KGLOBHD4","KGLOBHD5","KGLOBHD6","KGLOBHD7","KGLOBPC0","KGLOBPC6","KGLOBTP0","KGLOBT00","KGLOBT01","KGLOBT02"
,"KGLOBT03","KGLOBT04","KGLOBT05","KGLOBT35","KGLOBT06","KGLOBT07","KGLOBT08","KGLOBT09","KGLOBT10","KGLOBT11","KGLOBT12","KGLOBT13","KGLOBT14","KGLOB
T15","KGLOBT16","KGLOBT17","KGLOBT18","KGLOBT19","KGLOBT20","KGLOBT21","KGLOBT22","KGLOBT23","KGLOBT24","KGLOBT25","KGLOBT26","KGLOBT28","KGLOBT29","K
GLOBT30","KGLOBT31","KGLOBT27","KGLOBT32","KGLOBT33","KGLOBWAP","KGLOBWCC","KGLOBWCL","KGLOBWUI","KGLOBWDW","KGLOBT42","KGLOBT43","KGLOBT44","KGLOBT45
","KGLOBT46","KGLOBT47","KGLOBT49","KGLOBT50","KGLOBT52","KGLOBT53","KGLOBTL0","KGLOBTL1","KGLOBTS0","KGLOBTS1","KGLOBTN0","KGLOBTN1","KGLOBTN2","KGLO
BTN3","KGLOBTN4","KGLOBTN5","KGLOBTS2","KGLOBTS3","KGLOBTS5","KGLOBTT0","KGLOBCCE","KGLOBCCEH","KGLOBCLA","KGLOBCLC","KGLOBCCC","KGLOBTS4","KGLOBCBCA"
,"KGLOBT48","KGLOBDSO","KGLOBDEX","KGLOBDPX","KGLOBDLD","KGLOBDIV","KGLOBDPS","KGLOBDDR","KGLOBDDW","KGLOBDBF","KGLOBDRO","KGLOBDCP","KGLOBDEL","KGLOB
DFT","KGLOBDEF","KGLOBDUI","KGLOBDCL","KGLOBDAP","KGLOBDCC","KGLOBDPL","KGLOBDJV","KGLOBACS","KGLOBTS6","KGLOBTS7","KGLOBT54","KGLOBT55","KGLOBT56","K
GLOBT57","KGLOBDCO","KGLOBDCI","KGLOBDRR","KGLOBDRB","KGLOBDWR","KGLOBDWB","KGLOBT58","KGLOBDOR","KGLHDMTX","KGLHDMVL","KGLHDMSP","KGLHDMGT","KGLHDDMT
X","KGLHDDVL","KGLHDDSP","KGLHDDGT","KGLHDBID","KGLHDBMTX","KGLHDBVL","KGLHDBSP","KGLHDBGT","KGLOBT59","KGLOBDCU","KGLOBPROP","KGLNACON","KGLNAO1N","K
GLHDMAR","KGLMPFLG","KGLOBAQP","KGLOBT60","KGLOBT61","KGLIMSCANS","KGLIMBYTESUNCOMP","KGLIMBYTESINMEM" FROM X$KGLCURSOR
2 3 4 5 6 7 8 9 10 11 12 13 14 15 
SQL> /
X","KGLHDDVL","KGLHDDSP","KGLHDDGT","KGLHDBID","KGLHDBMTX","KGLHDBVL","KGLHDBSP","KGLHDBGT","KGLOBT59","KGLOBDCU","KGLOBPROP","KGLNACON","KGLNAO1N","K
*
ERROR at line 13:
ORA-00904: "KGLHDMAR": invalid identifier

Describing the source tables used by the views, the columns that generated the error do not exist there. What?!

Looking up MOS – found this note, Invalid x_$ Objects After Upgrade (Doc ID 361757.1)

Although this note does not mention these views explicitly there is a part of that says that

"This is NOT a dictionary corruption, but the result of an unsupported operation.

.....

These x_$ views do not compile because they are based on x$ tables which have changed (columns dropped) and/or do not exist (X$ table dropped).

New (default) 10g & 11g databases do not have views with the prefix x_$.

Please note that this solution can be applied to any and all x_$ views found invalid after upgrade/migration.
These tables are built on x$ tables in the previous release and the same rules still apply."

So these are save to ignore or drop them.

Hope this helps.

Elisson Almeida

DO NOT uninstall Database Vault from a CDB!

Hi all,

This is just a note for you that are now fully into database upgrades. As you may know, the Database Vault (DV) option could be reported as not installed in source when converting non-CDB to PDB, and the target CDB has the option installed. However, be aware that is not supported to remove DV option in multitenant (singletenant included) environments.

From Doc ID 2380950.1:

IMPORTANT:  Never run dvremov.sql on a container database (CDB) / Multitenant environment.  Doing so will cause serious problems when upgrading the PDBs.

 

In case you run dvremov.sql in a 12.1 multi-tenant DB, then the only option you might have is to restore the database to the state before running dvremov.sql. Assuming you have this backup, of course.

So stay sharp! 😀

Some references:
How To uninstall / install Database Vault in a 12c database ? (Doc ID 2112167.1)
DBA_DV_STATUS Is INVALID (Due to “ORA-00942: Table Or View Does Not Exist”) (Doc ID 2380950.1)

Adaptive Query Optimization: SQL Plan Directives Causing High CPU after 12c Upgrade

Hello all!

As DBAs we are always being recommended by Oracle and also recommending to clients to update their databases, but we have to be aware about new features and their effects. This is the case of Adaptive Query Optimization and in this particular case on SQL Plan Directives.

SQL Plan Directives are one of the functionalities that compose the Adaptive Query Optimization in Oracle Database 12c. The basic idea is pretty interesting: The SQL Optimizer keeps reviewing bad (“suboptimal”, as they like to say) plans, tipically incorrect cardinality estimations and generates SQL plan directives, like for missing histograms or extended statistics.

In my case, just after the upgrade to 12c (made on Jan 27th), the CPU usage increased for the same report always ran in the database:

12c_upgrade

Ok, how to check it?

Continue reading

Upgrade your JDBC and JDK before Upgrade your Database to 12c Version!

Ok, now it’s everyone upgrading to 12c, right? Thanks God, this version was released in 2013!

But there is some things to be aware when planning an upgrade, specially regarding old applications and legacy. But pay attention! Not all of the requirements are necessary inside database. It’s the case os JDBC version requirement.

The database 12c documentation explicit mentions that JDBC versions 11.1.x and below are not supported anymore. It doesn’t mean that they don’t work, it’s only unsupported and you’ll have no assistance from MOS if you need. It’s better to avoid, right?

Anyway, if you check the JDBC support matrix, if you are in version 11.2 or below you are not supported since August/2015. So the Database 12c is helping you, that don’t have patching policy, to keep on right way. Thanks to Database 12c!

If this is your situation, I highly recommend you to upgrade the directly to JDBC version 7, the last available by now. See JDBC matrix version as:

captura-de-tela-2016-10-22-as-16-59-57

But test! Test in you dev/test/QA environments before upgrading in Production environment!

Why? Because JDBC also have his compatibility matrix. JDBC 7, for example, demands your JDK to be at least in version 7 (released in 2011!). So, it’s needed to be at least in JDK version 6, as you can see below.

captura-de-tela-2016-10-22-as-16-37-18(Click in the image to access the link)

OK doke?

Some interesting links for you:
Verifying a JDBC Client Installation
What are the various supported Oracle database version vs JDBC compliant versions vs JDK version supported?
Checking the Oracle JDBC Driver Version on a Weblogic Server (by Cristóbal Soto)

Matheus.