sql server - Changing the Column data type that exists in more than one table -

i'm using sql server , have column asset_serial exists in more 1 table.

the problem when wanted change type got this:

msg 5074, level 16, state 1, line 1
object 'pk_assets' dependent on column 'asset_serial'.

msg 5074, level 16, state 1, line 1
object 'fk_assigned_assets_assets' dependent on column 'asset_serial'.

msg 4922, level 16, state 9, line 1
alter table alter column asset_serial failed because 1 or more objects access column.

any suggestions...?

asset_serial primary key of current table , foreign key table first should drop 2 constraint , alter field in both tables , @ last create constraints again

if (object_id('fk_constraintname', 'f') not null) begin //drop constraint     alter table [tablename] drop constraint [fk_constraintname]     alter table [tablename] drop constraint [pk_constraintname] //alter table change column      alter table alter column asset_serial //create contraints      alter table [tablename] add constraint pk_constraintname primary key (fieldname);        alter table [dbo].[tablename]          check add constraint [fk_tablename_tablename2] foreign key([asset_serial])         references [dbo].[tablename2] ([asset_serial]) end