i've been having a bit more of a play with this and have noticed that the line

OriginalSchema.value('Form[1]/Codes[1]/code[sql:column("y.myNum")][1]','varchar(max)')

is significationly slowing down my query.

each row in the table that houses the XML column is assigned to a Client.

A Client could have any number of rows.

It seems that the more rows there are, the slower it becomes - significantly.

One such Client has 8 rows. each row has an XML column with 400 'code', which i am referencing in the code line above, in this post.

That means it is 'cycling' through 3200 'code' (400 X 8).

with the above line in, it takes 6 seconds. without, it takes less than 1.

i'm wondering if there is a more efficient way of getting the same result?