One: Multitenant Architecture (188.8.131.52)Multi-tenant architecture is the new heavyweight feature of Oracle 12c (12.1), built-in multi-tenancy (multi-tenancy), a container database (container) that can hold multiple pluggable Databases, Each pluggable database is independent of the other pluggable database.For external applications and developers, pluggable databa
Tags: des style blog http color io os using ARThis series of articles is a summary of some of the new features of Oracle database 12c, including database management, RMAN, high availability, and performance tuning, Syed Jaffer Hussain.1. Online renaming and repositioning of active data filesUnlike previous versions, th
Summary of new features in Oracle 12C SQL
Multiple indexes on the same field
Before Oracle 12c R1, a field cannot have multiple indexes in any form. Some may wonder why a field usually requires multiple indexes. In fact, there are
Oracle 12C new Features-extended data type, in 12c, the size of data types such as VARCHAR2, NAVARCHAR2, and raw are extended from 4K and 2K bytes to 32K bytes, compared to earlier versions. As long as possible, the size of the extended character decreases the use of the LOB
Add columns with default values in Oracle tables (including new 12C features) and oracle12c
This is a problem that I have been paying attention.
11G has been improved on this issue, and 12C has some new
Oracle 12C r2-new features-pdb disk I/O (iops,mbps) resource managementIn previous versions, there was no easy way to control the amount of disk I/O used by a single PDB. As a result, a PDB may run out of disk I/O and affect the performance of other PDB in the same instance. The Or
has been strengthened again, we can not set the NOT NULL here, greatly reducing the possible error operationSee the following experimental processCREATE table T, where more than 1 million rows of data.Sql> Select COUNT (*) from T; COUNT (*)---------- 1454256Add a column directly to the table (not set NOT NULL)Sql> ALTER TABLE t add MRDAI1 number default 10000; Table altered. elapsed:00:00:00.03The speed is swift. And, of course, as in 11G.After the setting is complete, if it is a newly inser
The new features of In-database archiving are introduced in Oracle Database 12c, which allows users to archive data by marking data rows on the table as inactive inactive. These inactive data rows can be compressed into one optimization and are not visible to the app by default. This feature enables the functionality a
One, DB default character set Al32utf8Specify the database character set when you create the database. Starting from Oracle Database 12c Release 2, if you use Oracle Universal Installer (OUI) or Oracle database Configuration Assistant (DBCA) to create a database and then the default database character set used is the U
reserved Records is 100Sql>set History 3;7. View Hist retained RecordsSql> hist list;1 show Con_name2 show parameter version;3 Show hist;Description: The number of records retained is calculated by command rather than by line count.8. Run the specified recordSql> hist;1 Select sysdate from dual;2 show Con_name3 Select date from dual;Sql> hist 2 run;Con_name------------------------------Cdb$root9. Edit the previous commandhist 1 edit;Description: You can operate like Linux VI and edit the retain
;Table altered.--View index statusSql>Col index_name for A25Select Table_name,index_name,status,blevel,leaf_blocks,orphaned_entries from user_indexes where index_name = ' IDX_ Andy_id ';table_name index_name STATUS blevel leaf_blocks ORP------------------------- ------------------------- -------- ---------- ----------- ---Andy_move idx_andy_id VALID 0 0 NO--Move online partition table errorSql> ALTER TABLE P_andy move online;ALTER TABLE P_andy move online*ERROR at line 1:Ora-14808:table does not
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