The Library is currently in the process of being upgraded from Oracle Database Version 18.104.22.168 to 22.214.171.124.
Demos are being upgraded to reflect the new Container paradigm as well as EBR (Edition Based Redefinition) and may contain references to CDBs, PDBs,
and other objects you may not be familiar with such as CDB_OBJECTS_AE: Welcome to 12c.
Have you viewed the Library's main Table of Contents? If not ... [Click Here]
... scroll down the page and you will find links to the largest collection of Oracle Database demos on the net.
Starting and stopping the 12c multi-tenant database means something very different from what starting and stopping a database 11gR2 or earlier. What is true in CDB$ROOT is not true in a PDB.
You will note a substanital change in this page from all library pages on this subject since the library was started.
Now the container name is critical to understanding what to expect and the word database is dropped as it is a term rendered essentially meaningless by the new architecture.
The startup demos assume that you have just rebooted the server and that no shell scripts have been written that automatically perform a startup function.
Startup commands executed in CDB$ROOT only affect CDB$ROOT whereas shutdown commands affect all PDBS. Startup and shutdown commands executed wthin a PDB only affect that single PDB. Here's why:
STARTUP consists of three separate operations:
NOMOUNT: Read the initialization file which provides information defining the instance (memory structures) and the location of the control files.
MOUNT: Read the control file which proves information on the location of tablespace data and temp files.
OPEN: Open the datafiles for access
OPEN RESTRICTED: Open the datafiles for access but limit connections to only those with RESTRICTED SESSION privileges
When you perform a STARTUP it reads the spfile, there is only one for the entire CDB and one of the control files, which are all identical and for which there is only one set for the entire CDB.
It then opens for access only those tablespaces and datafiles associated with CDB$ROOT and PDB$SEED.
This makes sense as you wouldn't want a situation where you had 20 PDBs, only 5 of which you actually were using, and they were all opened by default.
To open PDBs you must use the ALTER PLUGGABLE DATABASE syntax shown below.
SHUTDOWN also contains differences from what is "expected" behaviour.
If you are in CDB$ROOT and you issue a shutdown you shutdown everything: CDB$ROOT, PDB$SEED, and every PDB you have created: Makes sense because you only have on instance with memory structures.
But if you are logged into a PDB the rules are very different. A PDB is just a collection of files and has no memory structures so no matter what you do: SHUTDOWN, SHUTDOWN IMMEDIATE, SHUTDOWN ABORT
what you actually do is change the status of that one PDB, and only that one PDB, to MOUNT state.
SQL> alter system checkpoint;
SQL> shutdown abort;
SQL> startup restrict;
SQL> shutdown immediate;
Oracle Services On Windows
net start OracleService<SID>
c:\windows\system32 net start oracleserviceorabase
net stop OracleService<SID>
c:\windows\system32 net stop oracleserviceorabase
c:\windows\system32 net help helpmsg
The syntax of this command is:
NET HELPMSG message#
NET HELPMSG displays information about Windows network messages (such as error, warning, and alert messages).
When you type NET HELPMSG and the 4-digit number of the Windows error (for example, NET2182), Windows tells you about the message and suggests action you can take to solve a problem.
message# Is the 4-digit number of the Windows message you need help with. You don't need to type NET as part of the message number.