The document discusses how data is stored and organized in Microsoft SQL Server. It explains that rows in a table will always appear in the order they were inserted by default. It also describes how data is stored across 8KB pages that are grouped into extents for storage management, and how rows cannot span multiple pages. The document also provides an overview of different types of JOINs between tables like INNER, LEFT OUTER, RIGHT OUTER, and FULL OUTER JOINs.

1. Microsoft Sql Server
SELECT Statement

2. Natural Order
• When you do a SELECT FROM the table, the
rows will ALWAYS appear in the same order of
insertion
• It’s the “natural” chronologically-entered
order of the rows

3. Data Page
• Table data is stored as a collection of 8-KB
(8192-byte) pages.
• 8060 bytes for the data on each page.
• A row of data can not span multiple pages.

4. Pages and Extents
• The fundamental unit of data storage in SQL
Server is the page.
• Size of a page is 8 KB (96-byte header )
• Header store system information about the page:
• Page Number
• Page Type
• Free pace on the page
• Allocation unit ID

5. Data Page

6. Extents
• Page type: Data, Index, LOB,
ROW_OVERFLOW_DATA etc.
• Extents are the basic unit in which space is
managed.
• Extents are a collection of eight physically
contiguous pages

7. JOINING OF TABLES
• INNER JOIN
• LEFT OUTER JOIN
• RIGHT OUTER JOIN
• FULL OUTER JOIN

8. INNER JOIN

9. LEFT OUTER JOIN

10. RIGHT OUTER JOIN

11. FULL OUTER JOIN

12. THANK YOU