Indexing

Question

hi friends What is cluster.cluster index and non cluster index ?

Vineet Kumar Saini · Answer

Hi.. Akshay An index provides us ways of speeding the lookup of our information. Indexes fall into two categories: syn - CREATE [ UNIQUE ] [ CLUSTERED | NONCLUSTERED ] INDEX index_name on table(col) Clustered— You can have only one of these per table. If an index is clustered it means that the table on which the clustered index is based is physically sorted according to that index. this is auto create if table definition contain any primary key constraint create [unique] clustered index my on a(empno) Non-clustered— You can have many of these for every table. This is more along the lines of what you probably think of when you hear the word index. This kind of index points to some other value that will let you find the data. create unique nonclustered index my on a(empno) Please reply if answer is good.