Table Variables vs. Temp Tables in SQL Server

SQL Server has 'table variables' that doesn't exist in Oracle. In Oracle, we may use a cursor to get the same task done.  In addition, it seems worth taking a note on the difference between Table Variables and Temp Tables in SQL Server.

(1) How to create and use a Table variable :  Primary Key, Unique Key and Not Null allowed.

     DECALRE @tableVariableName TABLE
      (
         Column1    INT   IDENTITY(1,1),
         Column2    VARCHAR(10) NOT NULL,
         Column3    MONEY,
         ...
      )

      INSERT INTO  @tableVariableName
      SELECT customerID, name, salary
      FROM  customers


      SELECT *   FROM @tableVariableName

(2) Differences between Temp tables and Table Variables

•  DDL operation - Temp tables can be altered with a DDL operation while Table variables cannot be.
• Statistics - SQL Server collects statistices for temp tables but not for table variables. 
• Data access - SQL Server uses various strategies to access temp tables with the table statistices collected (index density, distribution, selectivity, etc). But it accesses table variables through a table scan only.
•  Performance - many people say that we get slightly better performance benefit with a table variable when working on a small data set (< 100,000 rows). But for a bigger data sets, a temp table seems to be a better choice.