update table set column = try_cast(column as numeric(7,3))
where try_cast(column as numeric(7,3)) is null

E
xamining data pages
You can view the contents of a data page by using the DBCC PAGE command, which allows you to view the page header, data rows, and row offset table for any given page in a database. Only system administrators can use DBCC PAGE. However, because you typically don’t need to view the contents of a data page, you can’t find information about DBCC PAGE in the SQL Server documentation. Nevertheless, in case you want to use it, here’s the syntax:
DBCC PAGE ({dbid | dbname}, filenum, pagenum[, printopt])

select goods.name
from goods
inner join prices ON prices.id = goods.id
where discount = 10
UNION ALL
select manufactures.name
from manufactures
inner join goods ON goods.manufacturer_id = manufactures.id
inner join prices ON prices.id = goods.id
where discount = 10
UNION ALL
select categories.name
from categories
inner join goods ON goods.category_id = categories.id
inner join prices ON prices.id = goods.id
where discount = 10