By Franck Pachot . Now that 12.2 is there, in the Oracle Public Cloud Service, I can share the slides of the presentation I made for Oracle Open World: 12cR2 Single-Tenant: Multitenant Features for All Editions from Franck Pachot I’ll give the same session in French, In Geneva on November 23rd at Oracle Switzerland. Ask me if you want an…
By Franck Pachot . A common question is: how to know which indexes are not used, so that I can drop them. If you tried to use index monitoring you probably have seen the limits of it which make it difficult to use. It has been improved in 12.2 so let’s check if it helps to release the stress of…
By Franck Pachot . 12cR2 is there. What’s new in SQL*Plus? For sure, you can’t expect lot of things from it. The new command line is the SQL*Developer sqlcl which aims to be 100% compatible with SQL*Plus with lot of more features. However, a few little things came here: default editor, command line history and easy row/LOB prefetch and statement…
By Franck Pachot . Oracle database 12.2 is there on the Database Cloud Service, in multitenant. In EE High Performance or Extreme Performance, you have the multitenant option: you can create 4096 pluggable database (instead of 252 in 12.1). If you are in lower services, you can create only one user PDB (not counting application root and proxy PDB). If…
By Franck Pachot . Here is, in my opinion, the most beautiful feature of the multitenant architecture. You know how I love Transportable Tablespaces. But here: No need to put the source in read/only No need to export/import the metadata logically No need for any option: available even in Standard Edition Standard Edition I am in Standard Edition here in…
By William Sescu Have you ever noticed a DB_UNKNOWN directory in your ASM structure? It usually happens in combination with spfile creation in ASM, or with RMAN spfile restores to ASM. The correct location is +DATA/<SID>/PARAMETERFILE/SPFILE.<#>.<#>, and an ASM alias from +DATA/<SID>/ pointing to it. But sometimes, the spfile ends up in +DATA/DB_UNKNOWN/PARAMETERFILE/SPFILE.<#>.<#> Technically no issue. The spfile in the…
By Franck Pachot . In multitenant you session can switch between containers. For example, since 12.1, a common user can switch explicitly between CDB$ROOT and any PDB with the ‘ALTER SYSTEM SET CONTAINER’. Any user connected to a PDB will also have it session switching implicitely when querying through metadata links and data links (new name for object links). In…
By Franck Pachot . Pluggable Databases are supposed to be isolated, containing the whole of user data and metadata. This is the definition of dictionary separation coming with multitenant architecture: only system data and metadata are at CDB level. User data and metadata are in separate tablespaces belonging to the PDB. And this is what makes the unplug/plug available: because…
By Franck Pachot . Database links are resolved with the server TNS_ADMIN configuration (sqlnet.ora and tnsnames.ora). You can use tnsping to check the resolution, but it supposes that you are on the server and have set the same environment as the one which started the database. In 12.2 you have a new package to check that: DBMS_TNS. It’s the kind…
By Franck Pachot . On Linux, when you move a datafile, with “mv” within the filesystem it’s just a rename. There is no copy. In 12c you can move a datafile online where oracle takes care of the move at OS level. But be careful. Even if you are in the same filesystem, moving a datafile online does a copy…
By William Sescu Do you see any differences between these two RMAN SHOW commands? RMAN> SHOW CONTROLFILE AUTOBACKUP FORMAT; RMAN configuration parameters for database with db_unique_name OCM121 are: CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO ‘%F’; # default and RMAN> SHOW CONTROLFILE AUTOBACKUP FORMAT; RMAN configuration parameters for database with db_unique_name OCM121 are: CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR…
By William Sescu By default, automatic control file backups are disabled (even with 12c), maybe for performance reasons. RMAN> SHOW CONTROLFILE AUTOBACKUP; RMAN configuration parameters for database with db_unique_name OCM121 are: CONFIGURE CONTROLFILE AUTOBACKUP OFF; # default And also good to know, the autobackup after structural changes does not occur for databases in NOARCHIVELOG mode. So, if your database is…
