Wednesday, 28 April 2010

Delete from a table which requires lookup in another table

Problem: To delete rows from TableA based on filter condition which requires a lookup on another table TableB.

Solution 1)

DELETE FROM TableA
FROM
TableA as A INNER JOIN
TableB as B on A.ID = b.ID
WHERE B.COL2 = ''someval' and B.COL3 = 'someval'

Solution 2)

DELETE FROM TableA
WHERE ID IN
(SELECT ID FROM TableB where COL2 = ''someval' and COL3 = 'someval')


Tuesday, 27 April 2010

Get distinct rows from DataTable

Found a method in data table object to get distinct rows:

DataTable dtTest = dtProduct.DefaultView.ToTable(true, new string[] { "PRODUCT", "NATURE", "TYPE" });

The first parameter has to be 'true' to get distinct rows, the second is the list of columns to return.

Cheers.

C# Reactive Extensions - Buffer and Window

I was going through Buffer and Window in RX, thought a few examples would help clear the differences. First create a buffer of even numbe...