sp_unbindefault (Transact-SQL MetaData) Definition

Please note: that the following source code is provided and copyrighted by Microsoft and is for educational purpose only.
The meta data is from an SQL 2012 Server.

I have posted alot more, find the whole list here.

Goto Definition or MetaData

Definition:

sys.sp_unbindefault(nvarchar @objname
, varchar @futureonly)

MetaData:

 create procedure sys.sp_unbindefault -- - 1996/08/13 13:34  
    @objname nvarchar(776),            --  table/column or datatype name  
    @futureonly varchar(15) = NULL  --  flag to indicate extent of binding  
as  
    declare @futurevalue varchar(15)    --  the value of @futureonly that causes  
                                        --   the binding to be limited  
  
    declare  
        @vc1            nvarchar(517)  
    declare  
        @tab_id            int  
        ,@col_id        int  
        ,@colname        sysname  
        ,@cur_default    int  
        ,@xusertype        int  
        ,@schid            int  
  
        ,@UnqualObj        sysname  
        ,@QualObj1        sysname  
        ,@QualObj2        sysname  
        ,@QualObj3        sysname  
  
    set cursor_close_on_commit    off  
    select @futurevalue = 'futureonly'  --  initialize @futurevalue  
  
    --  When a default or rule is bound to a user-defined datatype, it is also  
    --   bound, by default, to any columns of the user datatype that are currently  
    --   using the existing default or rule as their default or rule.  This default  
    --   action may be overridden by setting @futureonly = @futurevalue when the  
    --   procedure is invoked.  In this case existing columns with the user  
    --   datatype won't have their existing default or rule changed.  
  
    --  get name parts --   
    select @UnqualObj = parsename(@objname, 1),  
            @QualObj1 = parsename(@objname, 2),  
            @QualObj2 = parsename(@objname, 3),  
            @QualObj3 = parsename(@objname, 4)  
  
    if (@UnqualObj is null OR @QualObj3 is not null)  
    begin  
        raiserror(15253,-1,-1,@objname)  
        return (1)  
    end  
  
    -- -- -- -- -- -- -- -- --   Verify database.  
    if (@QualObj2 is not null and @QualObj1 is null)  
    begin  
        raiserror(15084,-1,-1)  
        return (1)  
    end  
  
    --  Try to resolve column first. We need to extract  
    --   and verify the table and column names and make sure the user owns  
    --   the table that is getting the default unbound.  
    if @QualObj1 is not null  
    begin  
        if (@QualObj2 is not null)  
            select @vc1 = QuoteName(@QualObj2) + '.' + QuoteName(@QualObj1)  
        else  
            select @vc1 = QuoteName(@QualObj1)  
  
        --  Find it and unbind it.  
        select @tab_id = c.object_id, @cur_default = c.default_object_id  
            from sys.columns c join sys.tables o  
                on c.object_id = o.object_id  
            where c.name = @UnqualObj  
                and o.object_id = object_id(@vc1,'local')  
        if @tab_id is not null  
        begin  
  
            if @cur_default = 0  
            begin  
                raiserror(15236,-1,-1,@objname)  
                return(1)  
            end  
  
            if exists  
            (select    *  
                from    sys.objects o  
                where    @cur_default    = o.object_id  
                    and    @tab_id        = o.parent_object_id)  
                begin  
                    raiserror(15049,-1,-1, @objname)  
                    return (1)  
                end  
  
            BEGIN TRANSACTION  
  
            --  Since binding a default is a schema change,  
            --   update schema count for the object in the sysobjects table.  
            EXEC %%Object(MultiName = @vc1).LockMatchID(ID = @tab_id, Exclusive = 1, BindInternal = 0)  
  
            --  Check again that table and column exist  
            if @@error = 0  
                select @col_id = column_id  
                    from sys.columns  
                    where object_id = @tab_id  
                        and name = @UnqualObj  
            if @col_id is null  
            begin  
                COMMIT TRANSACTION  
                raiserror(15148,-1,-1, @objname)  
                return(1)  
            end  
  
            EXEC %%ColumnEx(ObjectID = @tab_id, Name = @UnqualObj).SetDefault(ID = 0)  
            --  EMDEventType(x_eet_Unbind_Default), EMDUniversalClass(x_eunc_Table), src major id, src minor id, src name  
            --  -1 means ignore target, target major id, target minor id, target name,  
            --  # of parameters, 5 parameters  
            EXEC %%System().FireTrigger(ID = 242, ID = 1, ID = @tab_id, ID = @col_id, Value = @UnqualObj,  
                ID = -1, ID = 0, ID = 0, Value = NULL, ID = 2,  
                Value = @objname, Value = @futureonly, Value = NULL, Value = NULL, Value = NULL, Value = NULL, Value = NULL)  
  
            COMMIT TRANSACTION  
            raiserror(15519,-1,-1)  
            return (0)  
        end  
    end  
  
    --  We're unbinding to a user type.  In this case, the @objname  
    --   is really the name of the user datatype.  
    --   When we unbind to a user type, any existing columns get changed  
    --   to the new binding unless their current binding is not equal  
    --   to the current binding for the usertype or if they set the  
    --   @futureonly parameter to @futurevalue.  
    if @tab_id is null  
    begin  
  
        BEGIN TRANSACTION  
  
        --  Get the current default for the datatype.  
        if @QualObj2 is null  
               select @cur_default = default_object_id, @xusertype = user_type_id,  
                       @schid = schema_id  
                    from sys.types  
                    where user_type_id = type_id(@objname)  
          
        --  Ex-lock and check permission  
        if not (@xusertype is null)  
        begin  
            EXEC %%ScalarType(MultiName = @objname).LockMatchID(ID = @xusertype, Exclusive = 1)  
            if (@@error <> 0)  
                select @xusertype = null  
        end  
  
        if @xusertype is null  
        begin  
            COMMIT TRANSACTION  
            raiserror(15148,-1,-1,@objname)  
            return (1)  
        end  
          
        if @cur_default = 0  
        begin  
            COMMIT TRANSACTION  
            raiserror(15237,-1,-1,@UnqualObj)  
            return (1)  
        end  
  
        EXEC %%ScalarType(ID = @xusertype).SetDefault(ID = 0)  
        raiserror(15520,-1,-1)  
  
        --  Now see if there are any columns with the usertype that need the new binding.  
        select @futureonly = lower(@futureonly)  
        if isnull(@futureonly, ' ') <> @futurevalue  
        begin  
            declare    @cur_tab_id        int  
                    ,@bad_tab_id    int  
  
            select    @cur_tab_id = 0        --  detect table id change for lock schema  
                    ,@bad_tab_id = 0    --  skip bad tables (dropped, etc)  
  
            declare ms_crs_unbindefault_1 cursor local static for  
                select    distinct  
                        c.object_id, c.column_id  
                    from sys.columns c join sys.tables o  
                        on c.object_id = o.object_id  
                    where c.user_type_id = @xusertype  
                        and ( (c.default_object_id = 0) or  
                            (c.default_object_id = @cur_default))  
                        order by c.object_id  
                        for read only  
  
            open ms_crs_unbindefault_1  
  
            fetch next from ms_crs_unbindefault_1 into  
                @tab_id, @col_id  
  
            while @@fetch_status = 0  
            begin  
  
                if @cur_tab_id <> @tab_id    --  not same table  
                begin  
                    select @cur_tab_id = @tab_id  
                    select @vc1 = quotename(schema_name(OBJECTPROPERTY(@tab_id,'SchemaId'))) + '.'  
                                + quotename(object_name(@tab_id))  
  
                    EXEC %%Object(MultiName = @vc1).LockMatchID(ID = @tab_id, Exclusive = 1, BindInternal = 0)  
                    if @@error <> 0            --  bad table, eg. removed  
                        select @bad_tab_id = @tab_id  
                end  
  
                if @bad_tab_id <> @tab_id    --  table schema locked  
                begin  
                    --  Column cannot be dropped due to type shared lock  
                    select @colname = COL_NAME(@tab_id, @col_id)  
                    EXEC %%ColumnEx(ObjectID = @tab_id, Name = @colname).SetDefault(ID = 0)  
                end  
  
                fetch next from ms_crs_unbindefault_1 into  
                    @tab_id, @col_id  
  
            end  
  
            deallocate ms_crs_unbindefault_1  
            raiserror(15521,-1,-1)  
        end  
  
        --  EMDEventType(x_eet_Unbind_Default), EMDUniversalClass(x_eunc_Type), src major id, src minor id, src name  
        --  -1 means ignore target, target major id, target minor id, target name,  
        --  # of parameters, 5 parameters  
        EXEC %%System().FireTrigger(ID = 242, ID = 6, ID = @xusertype, ID = 0, Value = NULL,  
            ID = -1, ID = 0, ID = 0, Value = NULL, ID = 2,  
            Value = @objname, Value = @futureonly, Value = NULL, Value = NULL, Value = NULL, Value = NULL, Value = NULL)  
  
        COMMIT TRANSACTION  
    end  
  
    return (0) --  sp_unbindefault