‎2008 Apr 29 2:08 PM
hi frnds,
i am new to sdn. pls answer this question.
1. what is primary index and secondary index?
thanks in advance
‎2008 Apr 29 2:20 PM
primary key is created when u create the db table.
secondar index is when the primary key doesnt satistfy your data fetch needs, as in you select data more frequently which is not part of the primary key fields, then secondary index is created.
During runtime, the optimizer chooses the primary index , if the where condition doesnt form the part of primary key fields, then it search for the secondary index and uses the index to fetch the data fast.
regards,
madhumitha
‎2008 Apr 29 2:14 PM
‎2008 Apr 29 2:16 PM
Hi,
Primary index is aumatically generated the movement we create a database table.
the secondary index is given in addition to the Primary Index already existing for the table ,so as to improve the data retrieval consistently, so as a result the perforamance is also increased and secondary index is also helpful in reducing the load on the Database, but do not create a lot of this..
‎2008 Apr 29 2:20 PM
primary key is created when u create the db table.
secondar index is when the primary key doesnt satistfy your data fetch needs, as in you select data more frequently which is not part of the primary key fields, then secondary index is created.
During runtime, the optimizer chooses the primary index , if the where condition doesnt form the part of primary key fields, then it search for the secondary index and uses the index to fetch the data fast.
regards,
madhumitha
‎2008 Apr 29 2:21 PM
hi
primary index for an table consist of all its key field
where as ssecondary index is created by us
and if no index is created table always refer to primary index for all purpose to fetch the data
‎2008 May 02 2:20 PM