Datasheet

Importing
With importing, you are making a copy of the data and filling a newly created
table with the copied data. After importing, the data is disconnected from the
source from which it was imported. If any future changes are made to the out-
side source, they will not be reflected in the Access data. This is true in the
other direction, in that changes to your Access data will not affect the original
source. After importing a table, it is common to treat that Access data as the
true data source. Any updating, appending, or deleting will be done to the
Access data. Then, when it is time to analyze the data, you can be sure it
reflects the latest, most accurate version of that data.
Linking
When you link a table to Access, you are creating a pointer to another data
source. When the Access database is opened, it establishes links to its outside
data source and displays the data as if it were a regular local Access table.
However, there is no data residing in Access. The data is physically located on
another computer, server, or source. If you change the data in the Access table,
the true data source will reflect that change. If you change the original data
source, those changes will be reflected when you reopen the linked table.
Things to remember about importing data
Your decision whether to import or link data depends on the situation. When
you import data, it resides directly in the Access file, so operations on that data
perform much faster. With linked tables, you may be dependent on the speed
of the connection with the data source or the speed of the database engine at
the other end.
One important point to remember is that when importing data, you can select
to create a new table or import your data into an existing table. If you choose to
create a new table, Access makes a copy of the data to import, then attempts to
determine the column names and field data types. Access may make an incor-
rect assumption about the data type, but you can go back and make the neces-
sary changes. If you choose to import data to an existing table, you must make
sure that the data types of the fields are compatible. If you attempt to import a
text string into a number field, for example, an error will occur.
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