Sriharsha

• Aug 23rd, 2005

 

Partitioning is a part of physical data warehouse design that is carried out to improve performance and simplify stored-data management. Partitioning is done to break up a large table into smaller, independently-manageable components because it: 
1. reduces work involved with addition of new data. 
2. reduces work involved with purging of old data. 
 
Two types of partitioning are: 
1. Horizontal partitioning.  
2. Vertical partitioning (reduces efficiency in the context of a data warehouse).

ravi kumar guturi

• Mar 10th, 2006

 

Partition is a delibrigate splitting of tables in to manageble parts,

By using partition, we increase the query performance by the time period of retrive from source and send to the target.

Mainly partitions 5 types including7.1

Keyrange partition,

Hasth partition,

Roundrabin partion,

List partition(7.1)

Composit partition

sithu

 Profile Answers by sithu 

• Mar 25th, 2006

 

1. Round Rabin partition2. Key range partition3. Hash partitionCheers,Sithu

prudhvi

• Sep 5th, 2006

 

There are 4 types of partitioning

they are 1)pass through 2)Round Robin 3)hash 4)Key range partition

DWH01

 Profile Answers by DWH01 

• Jul 9th, 2008

 

Oracle provides partitioning of Tables, Indexes and IOTs to split their contents into different partitions.  Each partition could be on a separate physical drive.  This provides faster performance for read / write operations, improves manageability, and increases availability of the database. 

In data warehouse this has great significance - when we want to load / refresh huge data, the cost of loading data as well as dropping / creating indexes can be huge.  This can be reduced by partitioning the tables and indexes.

Tables are partitioned using a 'partitioning key', a set of columns which determine in which partition a given row will reside. Oracle9i provides five techniques for partitioning tables:

• Range Partitioning: Each partition is specified by a range of values of the partitioning key (e.g. a trade table can be partitioned by the year of the trade date')
• List Partitioning: Each partition is specified by a list of values of the partitioning key (sales data can be partitioned by region in which countries falling under NA, EMEA etc can be grouped under separate lists.)
• Hash Partitioning: A hash algorithm is applied to the partitioning key to determine the partition for a given row
• Composite Range-Hash Partitioning: A combination of the Range and Hash partitioning technique. The table is first range-partitioned, and then each individual range-partition is further sub-partitioned using the hash partitioning technique. All sub-partitions for a given range partition together represent a logical subset of the data.
• Composite Range-List Partitioning: A combination of the Range and List partitioning technique. The table is first range-partitioned, and then each individual range-partition is further sub-partitioned using a list partitioning technique.

Salman Baig

• Aug 17th, 2014

 

Partitioning is a technique which partitions data across several disks and exploits bandwidth of disks by storing and retrieving in parallel.It reduces the time required to perform the access of data which is done by partitioning tuples of a relation.

Access of Data can be in three ways :-(

a)Scanning Entire Relation.
(b)Point Queries.
(c)Range Queries.

To satisfy this three access of data technique we have three following techniques:-

(a)Round Robin
(b)Hash Partitioning.
(c)Range Partitioning.