oracle 12c new features for dba arup nanda

; INSERT INTO invisible_t (ID,NAME,PASSWD) VALUES (1, ' Andy ', 1);1 row created.sql> INSERT INTO invisible_t (Id,name) VALUES (2, ' andy02 ');1 row created.3. Query statusSql> select * from invisible_t;ID NAME---------- --------------------1 Andy2 andy02Sql> select Id,name from invisible_t;ID NAME---------- --------------------1 Andy2 andy02Sql> select id,name,passwd from invisible_t;ID NAME PASSWD---------- -------------------- --------------------1 Andy 12 andy024. Modify field to visible 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

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

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

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

(2, Seq_session.nextval); SQL>Select* fromSCOTT.GTT; ID Seq_number---------- ----------1 3 2 4SQL>Continue the test.--end of session, sequence value will be resetSql>conn tiger/Tigersql>drop synonym GTT; SQL>drop synonym seq_session; SQL>create synonym GTT forSCOTT.GTT; SQL>create synonym Seq_session forscott.seq_session; SQL>Select* fromgtt;no rows Selectedsql>sql> INSERT INTO GTT values (1, Seq_session.nextval); sql> INSERT into GTT values (2, Seq_session.nextval);-I

Adding columns with default values to tables in Oracle (including new 12C features) This is a problem that I have been paying attention. 11G has been improved on this issue, and 12C has some new

New Features of Oracle DB 12c: raw device bare devices are no longer supported, oracle12c New Feature of Oracle DB 12c: raw device is no longer supported. Reference:Announcement of De-S

New Features of Oracle 12C-online migration of table partitions or subpartitions Oracle 12c: new feature-online migration of table partitions or subpartitions. It is no longer necessar

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

Prior to the Oracle 12c version, the VARCHAR2 and NVARCHAR2 data types had a maximum length of 4000, with the extended maximum of 12c versions supported to 32767, or 32KB, and parameter Max_string_ The size is the maximum length of the extended data type that controls the extended datatype: Standard: Represents the length limit before

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