Do statistics referencing a column prevent that column from being dropped?

Question

I'm trying a very simple drop column statement:

alter table MyTable drop column MyColumn

and receiving several errors along the lines of

Msg 5074, Level 16, State 1, Line 1
The statistics '_dta_stat_1268251623_3_2' is dependent on column 'MyColumn'.

followed ultimately by

Msg 4922, Level 16, State 9, Line 1
ALTER TABLE DROP COLUMN MyColumn failed because one or more objects access this column.

I didn't think statistics prevent a column from being dropped. Do they? If so, since these are apparently auto-created statistics I can't depend on the names being the same across multiple copies of the same database, so how could I drop all such statistics in an upgrade script to be executed on a different database?

Answer 1

The code proposed in JNK answer does not work, but the idea is good. If you want to delete all user created statistics this my tested solution :

DECLARE @sql NVARCHAR(MAX)

DECLARE statCursor CURSOR FOR 
SELECT 
    'DROP STATISTICS ' + QUOTENAME(SCHEMA_NAME(t.schema_id)) 
                        + '.' + QUOTENAME(t.name) 
                        + '.' + QUOTENAME(st.name) AS sql
FROM
    sys.stats AS st 
    INNER JOIN sys.tables AS t
        ON st.object_id = t.object_id
WHERE
    st.user_created = 1
ORDER BY 1;

OPEN statCursor;

FETCH NEXT FROM statCursor INTO @sql
WHILE @@FETCH_STATUS = 0  
BEGIN  
    PRINT @sql
    EXEC sp_executesql @sql
    FETCH NEXT FROM statCursor INTO @sql
END  
CLOSE statCursor  
DEALLOCATE statCursor