(
EmpId Int,
EmpName Varchar(8000)
)
When you first create a new table, there is no index created by default.
In technical terms, a table without an index is called a “heap”.
We can confirm the fact that this new table doesn’t have an index by taking a look at the sysindexes system table,
which contains one for this table with an of indid = 0.
The sysindexes table, which exists in every database, tracks table and index information.
“Indid” refers to Index ID, and is used to identify indexes.
An indid of 0 means that a table does not have an index, and is stored by SQL Server as a heap.
Source:
http://www.sql-server-performance.com/2004/index-data-structures/