Tuesday, November 3, 2009

SQL Server FAQ : Single line Answers

Log Shipping: Log Shipping provides a means to maintain a secondary server on an automated basis using a chain of transaction log backups.

Replication: Distribute data from Master database to one or more Secondary databases.

Data Mining: Making predictions about data.

Full Text Indexes: Index that give ability to query large volumes of unstructured data rapidly.

Clustering: To protect system against hardware failures.

Trouble Shooting tools:

Dynamic Management Views (DMV) and Functions (DMF)
System Monitor
SQL Server Profiler
Database Tuning Advisor

Clustered Index :A clustered index is an index where the leaf level of the index contains the actual data rows of the table

Heap: A table that has no index is referred to as a heap

Difference Between Clustered Index and Heap:
A clustered index has the data stored logically in the order of the index key, a heap has no ordering of rows or pages

Difference Between Len () and DataLength ():

Len() does not work on text, N text, image data types. But DATALENGTH() does work

ACID stands for Atomicity, Consistency, Isolation, and Durability

Transaction : A smallest unit of work in database

Lock Modes: The way in which a lock shares, or does not share records it is currently working on, are called Lock Modes

Index :An index is a structure within SQL that is used to quickly locate specific rows within a table

Deadlock: Itrefers to the condition in which one resource is waiting on the action of a second, while that second action is waiting on the first

Index key : An index is defined on one or more columns

Locks: The SQL default method of controlling data integrity.

Transactions: TSQL's smallest unit of work.

ACID: An acronym used to describe a perfect and consistent transaction.

Lock Modes: The way a lock shares or does not share records its working on.

Blocking: When a transaction must wait for a record.

Deadlocks: An error condition occurring when two locks are stuck in a circular loop.

Lock Hints: TSQL commands to override SQL's default locking behavior.

Row Versioning: The new ability in SQL 2005 to keep copies of data changes.

No comments:

Post a Comment