IMPORT AND EXPORT

UTILITIES IN MS ACCESS

SUBMITTED BY:HARSH GOARROLL NO:5838

IMPORTING VS. LINKING DATABASE FILES

• You have the choice of importing or linking data from other databases, but how do you

• decide which type of access is best? Here are some guidelines.

• You should consider importing another database file when any of the following is true:

• ● The file you need is relatively small and is not changed frequently by users of the other

• database application.

• ● You don’t need to share the data you create with users of the other database application.

• ● You’re replacing the old database application, and you no longer need the data in the

• old format.

• ● You need to load data (such as customers or products as I mentioned earlier) from

• another source to begin populating your Access tables.

• ● You need the best performance while working with the data from the other database

• (because Access performs best with a local copy of the data in Access’s native format).

• On the other hand, you should consider linking another database file when any of the following

• is true:

• ● The file is larger than the maximum capacity of a local Access database (2 gigabytes).

• ● The file is changed frequently by users of the other database application.

• ● You must share the data on a network with users of the other database application.

• ● You’ll be distributing your application to several individual users, and you will need to

• make changes to the queries, forms, reports, and modules in the application without

• disturbing data already entered in the tables.

To copy data from a text file,

spreadsheet file, or database table

into an Access table. You can use

the imported data to create a new

table, or you can append (add) it to

an existing table that has a

matching data structure.

Import Options

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IMPORTING ACCESS FILES.

Importing Access Objects

• If the database from which you want to import data is another Access database, you can

• import any of the seven major types of Access objects: tables, queries, forms, reports, data

• access pages, macros, or modules. To achieve the same result, you can also open the source

• database, select the object you want, choose the Copy command from the Edit menu, open

• the target database, and then choose the Paste command from the Edit menu. Using the

• Import command, however, allows you to copy several objects without having to switch back

• and forth between the two databases.

• You can also click the Options button (which has been clicked in the preceding illustration)• to select additional options. If you import any tables from the source database,• you can select the option to import the table relationships (if any) defined for• those tables in the source database. If the object is a table, you can select the option to• import the table structure (the table definition) only or to import the structure and• the stored data. You can also select special options to import all custom menus and• toolbars (all command bars) from the source database (see Chapter 24, “The Finishing• Touches”) or all import/export specifications. (See the sidebar titled “Defining an• Import Specification,” page 207, for details.) You can also choose to import a query• object (the definition of the query) by choosing As Queries under Import Queries, or• you can ask Access to run the query and import the data results into a table by choosing• As Tables. (See Chapter 7, “Creating and Working with Simple Queries,” for details• about building and using queries.) Click OK to copy the objects you selected to the• current database.

Importing excel files

Importing Text Files

• A comma-separated and double-quote–qualified text file.

• A tab-separated text file.

A fixed-width text file.

Importing dBASEFiles

• An imported dBASE file.

Dbase-to-Access Data Type Conversions

• dBASE Data Type Converts to Access Data Type

• Character Text

• Numeric Number, Field Size property set to Double

• Float Number, Field Size property set to Double

• Logical Yes/No

• Date Date/Time

• Memo Memo

Linking Access Tables

LINKING TEXT AND SPREADSHEET FILES

• .Linking a text file or an Excel spreadsheet file is almost identical to importing these types of Files. (You cannot link Lotus 1-2-3 files, you can only import them.) As noted, you can only read linked text files, but you can update and add new rows (but not delete rows) in Excel spreadsheet files.

To link a spreadsheet file or a text file-

• 1 Open the Access database to which you want to link the file. If that database is already

• open, switch to the Database window.

• 2 Choose the Get External Data command from the File menu, and then choose Link

• Tables from the submenu. Access opens the Link dialog box, which lists the types of

• files you can link.

• 3 Select Microsoft Excel or Text Files, as appropriate, in the Files of type drop-down

• list, and then select the folder and the name of the file that you want to link. If you’re

• connecting over a network, select the logical drive that is assigned to the network

• server that contains the database you want. If you want Access to automatically connect

• to the network server each time you open the linked file, type the full network

• location in the File name box instead of choosing a logical drive, path, and file name.

• For example, on a Windows network you might enter a network location such as:

• \\filesvr\excel\shared\companies.xls

• 4 Click the Link button to start the Link Spreadsheet Wizard or the Link Text Wizard.

• 5 Follow the steps in the wizard, which are identical to the steps for importing a spreadsheet

• or text file.

Modifying Linked Tables• You can make some changes to the definitions of linked tables to customize them

for use in• your Access environment. When you attempt to open the table in Design view,

Access opens• a dialog box to warn you that you cannot modify certain properties of a linked

table. You can• still click OK to open the linked table in Design view.• You can open a linked table in Design view to change the Format, Decimal Places,

Caption,• Description, and Input Mask property settings for any field. You can set these

properties to• customize the way you look at and update data in Access forms and reports. You

can also give• any linked table a new name for use within your Access database (although the

table’s original• name remains unchanged in the source database) to help you better identify the

table or to• enable you to use the table with the queries, forms, and reports that you’ve

already designed.• Changing a table’s design in Access has no effect on the original table in its source

database.• However, if the design of the table in the source database changes, you must relink

the table to• Access. You must also unlink and relink any table if your user ID or your password

changes

Using the Linked Table ManagerIf you move some or all of your linked tables to a different location, you must either deleteyour linked tables and relink them or update the location information before you can openthe tables. You can easily update the location information in the table links by using theLinked Table Manager. To use this handy utility, open the database that contains linked tablesthat need to be relinked, choose Database Utilities from the Tools menu, and then chooseLinked Table Manager from the submenu. The utility opens a dialog box that displays all thelinked tables in your database, as shown in Figure 6-14. Simply select the ones that you thinkneed to be verified and updated, and then click OK. If any of the linked tables have beenmoved to a different location, the Linked Table Manager prompts you with a dialog box sothat you can specify the new file location. You can also select the Always prompt for newlocation check box to verify the file location for all linked tables.

• The Linked Table Manager dialog box.

To copy data and database objects

to another database, spreadsheet

file, or file format so that another

database or program can use the

data or database objects. You can

export data to a variety of

supported databases, programs,

and file formats.

Export Option

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