Category Archives: Oracle

ORACLE TUTORIALS

Oracle is most widely used Oracle database in the world. It has the capacity to handle large database and high transaction

Here I am presenting the Oracle tutorials on Various Oracle products

  1. Oracle database
  2. Oracle sql/plsql
  3. Oracle application
  4. Weblogic
  5. Performance tuning.

These articles will be  really help in understanding the oracle products and getting started on Oracle system

Top Oracle 12c New Features for developers

Last updated on November 26th, 2018 at 05:13 pmOracle has released 12c with lot of new fetaures. Here in this article,I would presenting the top Oracle 12c New Features for developers I have categorized the features in the broad category to make it easier to understand and use SELECT IMPROVEMENTS 1) Top-N feature A Top-N query allows us to retrieve the top or bottom N rows … Continue reading Top Oracle 12c New Features for developers »

Flashback PDB in Oracle Database 12c Release 2

Last updated on November 26th, 2018 at 05:12 pmOracle database 12c Release 2 provides flashback capability at the individual PDB level. Lets discuss the new feature. we can learn about Flashback database in general from below links Flashback Database explained and limitation For the oracle database to be flashback, archive log mode and flashback mode should be on How to put database in archive log … Continue reading Flashback PDB in Oracle Database 12c Release 2 »

PDB Relocate in Oracle database 12c Release 2

Last updated on November 26th, 2018 at 05:14 pmA pluggable database is a self-contained, fully-functional Oracle database. We often need to move the pluggable database from one CDB to another CDB. This will be a unplug/plug operation where outage will depend on the location of source and destination CDB 1) When moving between servers with shared storage, such as is typically the case in Cloud … Continue reading PDB Relocate in Oracle database 12c Release 2 »

How to remotely clone a PDB or non-CDB in Oracle Database 12.1

Last updated on November 26th, 2018 at 05:13 pmMany times, we may need to copy the remote PDB to Local PDB for testing purpose. The case would be copying Production PDB to Development PDB box. Some times , we may want to migrate the non-CDB to PDB to make sure Multitenant features in the Oracle database Restriction for doing this 1)The default tablespaces for each … Continue reading How to remotely clone a PDB or non-CDB in Oracle Database 12.1 »

Hot PDB cloning in Oracle database 12.2

Last updated on November 26th, 2018 at 05:14 pmIn Oracle database release 12.1, in order to clone a PDB, The source PDB must be quiescent(read only mode) for the duration of the clone operation. So it was called a “cold clone” operation because it involved an outage (from a transactional perspective) in the source database. This applies for both the same CDB clone or Remote … Continue reading Hot PDB cloning in Oracle database 12.2 »

Refreshable PDB in Oracle Database 12.2

Last updated on November 26th, 2018 at 05:14 pmRefreshable PDB is a new features introduced in 12.2 . It builds upon hot clone capability in Oracle Database 12.2. It basically means we can refresh the remote PDB from source PDB on regular intervals by just applying the incremental redo This feature eliminates the need to re-create a cloned environment from scratch and also ensures that … Continue reading Refreshable PDB in Oracle Database 12.2 »

Oracle Enqueue and locks(Oracle table locks): How it works

Enqueue and locks

Oracle database is the widely used database in industry .Here I am trying to explains  about oracle locks Topics Covered What is Oracle Enqueue and locks What is Enqueue identifier? What is Enqueue resource? How is the lookup done in Resource table? How is Enqueue operations works? How is the queue checked when lock is release or converted Common Types of Enqueue Views and Table … Continue reading Oracle Enqueue and locks(Oracle table locks): How it works »

Coalesce Function in Oracle

Last updated on October 30th, 2018 at 04:28 amCoalesce Function is a useful function in oracle and it is very useful when we want to return first non null values in the list expr1 : This is returned if it is not null expr2: This is returned if it is not null and first expression is null exprn: This is returned if the preceding expression … Continue reading Coalesce Function in Oracle »

NVL2 function in Oracle

Last updated on October 30th, 2018 at 04:33 amNVL2 function is a nesting function .It examines the first impression, if the the first impression is not null ,then NVL2 function returns the second expression. if the first impression is null, then it return the third expression. expr1: it is the source values or expression which may contain null. You can provide column name,function on the … Continue reading NVL2 function in Oracle »

NVL function in Oracle

NVL function is a nesting function which is used to substitute null values with certain values In the above syntax expr1 : it is the source values or expression which may contain null. You can provide column name,function on the column name expr2 : It is the target value which will be placed in case null is returned from expr1 If expr1 is null, then … Continue reading NVL function in Oracle »

Update statement in oracle

Update statement in oracle is used to update the existing rows in the table. It is a DML statement. DML stand data manipulation language. We can use this statement to update specific rows ,set of rows or all rows in the table. Syntax is given below Table : It is the table name which need to be updated column : it is the single column … Continue reading Update statement in oracle »