The Column object allows you to define the fields contained in a table or a key. The Columns collection contains all of the columns for a key or a table.
Use the Append method to create a new column and automatically add the column to the Columns collection. To set the data type of a column, specify a constant contained in the DataTypeEnum enumeration.
{Append a column named "Date" with a date data type.}
tableColumn = adoxTable.Columns.Append("Date", ADOX.adDate);
The following table lists the Dexterity data types and the corresponding ADOX types.
![[spacer]](1p.gif){kind=small}
|
Dexterity type |
ADOX type |
Description |
|---|---|---|
|
Boolean |
adBoolean |
Boolean |
|
Byte |
adUnsignedTinyInt |
Unsigned character |
|
Integer |
adSmallInt |
Short |
|
Long |
adInteger |
Long |
|
String Text |
adWChar adVarWChar |
String |
|
Currency |
adCurrency |
Currency |
|
Vcurrency |
adSingle adDouble adDecimal |
Single Double Decimal |
|
Date Time Datetime |
adDBDate adDBTime adDBDateStamp |
Date |
|
Reference |
adDispatch (unsupported) |
IDispatch* |
|
A typed COM reference |
adUnknown (unsupported) |
IUnknown* |
When you create a table, create the table columns before you create key columns. The columns in a key must also be in the table that the key is associated with.
You can retrieve an existing column from the Columns collection with the Item property by the number associated with the column.
{Retrieve the first column from the table.}
tableColumn = adoxTable.Columns.Item[0];
You can also access columns by the column name.
{Retrieve the column named "BuyerID".}
tableColumn = adoxTable.Columns.Item["BuyerID"]