How does TableSample in FROM clause of a SELECT Query work?

TableSample clause started with SQL Server 2015 limits the number of rows returned from a table to a sample % or sample numbers. In fact, it may not provide the specified rows of %. Also, it is not for tables with too few rows.

Here is how TableSample is defined in the MSDN site:

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TABLESAMPLE (10 PERCENT) /*Return a sample 10 percent of the rows of the result set. */
TABLESAMPLE (15 ROWS) /* Return a sample of 15 rows from the result set. */.

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For these scenarios it cannot be applied:

Derived tables
Linked Server Tables
Tables from Table-Valued functions
Row-set functions
Open XML

This here is the syntax for TableSample clause:

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TABLESAMPLE [SYSTEM] (sample_number [ PERCENT | ROWS ] )

[ REPEATABLE (repeat_seed) ]

TableSample in FROM Clause does not behave as defined in the syntax and could provide surprising results:

I queried the Northwind databases Orders table using the following syntax in SQL Server 2016 Developers edition.

SELECT * FROM Orders TableSample(10 Percent)

SELECT * FROM Orders TableSample (10)--surprisingly this does not result in error

SELECT * FROM Orders TableSample (10 ROWS)

These queries were run a number of times and the rows returned were variable from run to run and some times resulted in 0 returned rows.

More details here:
https://hodentekmsss.blogspot.com/2018/03/tablesample-in-from-clause-to-limit.html

How do you use ForEach loop in Windows Power Shell?

'For Each Loop' is used in all programming languages the notation may be slightly different. We already saw how we do it writing the array elements in my previous post here.

The ForEach-Object has other simpler aliases as shown here:

You can also access all Windows Objects if you use WMI as shown here.

These are my logical drives: