Databases Reference
In-Depth Information
Scanning
Let's start with the simplest example, by scanning a heap which, as shown in Table 2-1,
is performed by the Table Scan operator. The following query on the
AdventureWorks
database will use a table scan, as shown in Figure 2-1.
SELECT
*
FROM
DatabaseLog
Listing 2-1.
Figure 2-1:
A Table Scan operator.
Similarly, the following query will show a Clustered Index Scan operator, as shown in the
plan on Figure 2-2:
SELECT
*
FROM
Person
.
Address
Listing 2-2.
Figure 2-2:
A Clustered Index Scan operator.
