Benefits Of Deprecated Data Types

Raul Gonzalez shows how to get one of the benefits of older, deprecated data types using (MAX) data types:

We can see that our table is managed by two different allocation units, IN_ROW_DATA and LOB_DATA, which means that all data within columns of the data types above, will end up in different pages by default, regardless of the size of the data.

This is the default behaviour for old LOB types, to be stored separately, but new LOB types (MAX) by default will try to get them In-Row if they are small enough to fit.

Having some of those documents In-Row will result in a serious increase in the number of pages to scan, therefore affecting performance.

Note that for the table scan we have used only the IN_ROW_DATA pages, making it much lighter than if we have to scan the sum of all pages.

This might be helpful for some situations, like where you rarely need to get to the LOB data.

Related Posts

Data Types In R

Ellen Talbot gives us an overview of the different data types in R: Now here’s something we didn’t cover in the video and is especially helpful if something just WILL NOT work and you’ve spent all morning panic eating biscuits. You can write checks to see if something is numeric, or an integer, with is.numeric() or is.integer(). The […]

Read More

Let’s Not Talk About Timestamp

Randolph West hits us with a misnamed SQL Server data type: It occurred to me that we haven’t covered the TIMESTAMP data type in this series about dates and times. TIMESTAMP is the Windows Millennium Edition of data types. It has nothing to do with date and time. It’s a row version. Microsoft asks that we stop calling it TIMESTAMP and use ROWVERSION instead. Much like DECIMAL is a […]

Read More

Categories

April 2017
MTWTFSS
« Mar May »
 12
3456789
10111213141516
17181920212223
24252627282930