Answer / sumit

Index Scan is nothing but scanning on the data pages from
the first page to the last page. If there is an index on a
table, and if the query is touching a larger amount of
data, which means the query is retrieving more than 50
percent or 90 percent of the data, and then optimizer would
just scan all the data pages to retrieve the data rows. If
there is no index, then you might see a Table Scan (Index
Scan) in the execution plan.

Index seeks are generally preferred for the highly
selective queries. What that means is that the query is
just requesting a fewer number of rows or just retrieving
the other 10 (some documents says 15 percent) of the rows
of the table.


In Index Scan the cost is proportional to the total number
of rows in the table. Thus, a scan is an efficient strategy
if the table is small or if most of the rows qualify for
the predicate.


In Index Seek the cost is proportional to the number of
qualifying rows and pages rather than to the total number
of rows in the table.

Answer / vasu

An index seek shows that the index is used in the table and
index scan shows that index is not used in table

How to execute multiple stored procedures at one time in sql server?

0 Answers  

---

Are semicolons required at the end of sql statements in sql server 2005?

0 Answers  

---

Why we need a group by clause?

4 Answers  

---

What is sql server english query?

0 Answers  

---

What is an entity-relationship diagram (erd)?

0 Answers  

---

What is normalization? Describe its different types.

0 Answers   Wipro,

---

Tell me about builtinadministrator?

0 Answers  

---

Tell me about Triggers?

3 Answers   Cap Gemini,

---

What does REVERT do in SQL Server 2005?

0 Answers   HCL,

---

your sql server is running out of disk space. You notice that there are several large files with ldf extensions what are these files? : Sql server administration

0 Answers  

---

explain different types of constraints? : Sql server database administration

0 Answers  

---

How to list all tables in the database using odbc_tables()?

0 Answers  

---