Convert Column From NVARCHAR(MAX) To Money And Then Back Again.

I need to always have a formatting of 999,999,999.00 in a column called PropertyMap9.

PropertyMap9 is always a nvarchar(max)

How do I SET a value using a CONVERT or CAST to accomplish this ?

Why does this give me a syntax error ? The PropertyMap7 set actually works and performs the calculation and sets the new value for that row, however the next line gives an error. I need all 3 columns PropertyMap9, 8, and 7 to always have the above formatting, while still maintaining the nvarchar(max) datatype in the column. HELP!


update PropertyMapValues



set PropertyMap7 = CONVERT(NVARCHAR(MAX),CAST(PropertyMap8 AS money) - (CAST(PropertyMap9 AS money)),1)

set PropertyMap9 = CONVERT(NVARCHAR(MAX),CAST(PropertyMap9 AS money))

END



Msg 102, Level 15, State 1, Procedure UpdatePropertyMap7, Line 59

Incorrect syntax near '='.