How to get datatypes of specific fields of an Access database using pyodbc?

I'm using pyodbc to data-mine a big database in a .mbd (access) file.

I want to create a new table taking relevant information from several existing tables (to then feed it to a tool).

I think I know all I need to transfer the data, and I know how to create a table given column names and datatypes, but I'm having trouble getting the datatypes (INTEGER, VARCHAR, etc.) of the respective columns in the existing tables. I need these types to create the new columns compatibly.

What I found on the internet (like this and this) is getting me into invalid-command trouble, so I think this is a platform-specific issue. Then again, I'm fairly green on databases.

Does anybody know how to get the types of these fields?

Conrad Frix

The reason why those articles aren't helping you is because they are for SQL Server. SQL Server has system tables that you can query to get the column data, MS Access doesn't. MS Access only lets you query the object names.

However ODBC does support getting the schema through its connection via the ODBC.SQLColumns functions.

According to this answer PyODBC exposes this via a cursor method

# columns in table x
for row in cursor.columns(table='x'):
    print row.column_name

As Mark noted in the comments you probably also want the row.data_type. The link he provided includes all the columns it provides

table_cat
table_schem
table_name
column_name
data_type
type_name
column_size
buffer_length
decimal_digits
num_prec_radix
nullable
remarks
column_def
sql_data_type
sql_datetime_sub
char_octet_length
ordinal_position
is_nullable: One of SQL_NULLABLE, SQL_NO_NULLS, SQL_NULLS_UNKNOWN.

I am not familiar with pyodbc, but I have done this in VBA in the past.

The 2 links you mentionned are for SQL Server, not for Access. To find out the data type of each field in an Access table, you can use DAO or ADOX.

Here is an example I did, in VBA with Excel 2010, where I connect to the Access database (2000 mdb format) and list the tables, fields and their datatypes (as an enum, for example '4' means dbLong). You can see in the output the system tables and, at the bottom, tables created by the user. You can easily find examples on internet for how to do something similar with ADOX. I Hope this helps.

Private Sub TableDefDao()
    Dim db As DAO.Database
    Set db = DAO.OpenDatabase("C:\Database.mdb")

    Dim t As DAO.TableDef
    Dim f As DAO.Field
    For Each t In db.TableDefs
        Debug.Print t.Name
        For Each f In t.Fields
            Debug.Print vbTab & f.Name & vbTab & f.Type
        Next
    Next
End Sub

来源：https://stackoverflow.com/questions/4539254/how-to-get-datatypes-of-specific-fields-of-an-access-database-using-pyodbc

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