Question

I want to programmatically create a new column in an MS Access table. I’ve tried many permutations of ALTER TABLE MyTable Add MyField DECIMAL (9,4) NULL; and got:

Syntax Error in Field Definition

I can easily create a number field that goes to a Double type, but I want decimal. I would very strongly prefer to do this in a single ALTER TABLE statement and not have to create a field and then alter it.

I am using Access 2003.

Answer 1

If you want to create a new column in an acces table, it is easy to use the DAO.tableDef object:

Dim my_tableDef As DAO.TableDef Dim my_field As DAO.Field  Set my_tableDef = currentDb.TableDefs(my_table) Set my_Field = my_tableDef.CreateField(my_fieldName, dbDecimal, myFieldSize) my_Field.decimalPlaces = myDecimalPlaces my_Field.defaultValue = myDefaultValue  my_tableDef.Fields.Append my_Field  set my_Field = nothing set my_tableDef = nothing 

Of course you can further delete it.

You might have the posibility to do so with ADODB (or ADOX?) object, but as long as you are working on an mdb file, DAO is straight and efficient.

PS: after checking on some forums, it seems there is a bug with decimal fields and DAO. http://allenbrowne.com/bug-08.html. Advices are ‘go for double'(which is what I do usually to avoid any loosy issues related to decimal rounding) or use ‘implicite’ ADO to modify your database

strSql = 'ALTER TABLE MyTable ADD COLUMN MyField DECIMAL (28,3);' CurrentProject.Connection.Execute strSql