Many people may need access to an organization's database.
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If a database is on a computer connected to a network, users can work with the database from their own computers.
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Also, more than one user can access the database at the same time.
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To share a database so that other users can access it, you need to place it in a shared folder.
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To open a shared database, you select ^UOpen Database^u from the ^UFile^u menu.
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And you click the database that you want to open.
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If you don't want other users to be able to access the database at the same time as you, you check the ^UExclusive^u checkbox.
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But to open the database in Shared mode, you leave the checkbox unchecked.
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Next you click ^UOpen^u.
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You can specify whether the database opens in Shared or Exclusive mode by default by choosing ^UTools - Options^u.
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You then click the ^UAdvanced^u tab.
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You can set the default open mode as either shared or exclusive.
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Setting the default open mode does not affect users accessing the database from other computers.
Also, it does not prevent any user from opening the database in shared, exclusive, or read-only mode.
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Then you click ^UOK^u.
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When several users are working on the same database at the same time, they may make changes that conflict with each other.
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Access includes features that help you to prevent and manage conflicting changes.
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To prevent conflicting changes being made to a table's design, Access doesn't allow you to open a table if another user has that table open in Design view.
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Suppose another user has the Customers table open in Design view.
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If you try to open the table in either Datasheet or Design view, Access tells you that the table is ^Rlocked^r.
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Access doesn't allow you to modify a table in Design view if another user has the table open in Datasheet view.
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Suppose another user has the Customers database open in Datasheet view.
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If you try to open the table in Design view, Access tells you that you can only open the table in read-only mode.
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Access also prevents you from modifying a table in Design view if another user has a query, form, or report based on the table open.
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To help prevent conflicting changes being made to records, Access allows you to lock the records that you are editing.
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Other users cannot change a record while it is locked.
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Suppose you are working on the Products table and want to lock the records while you are editing them.
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You select ^UTools - Options^u.
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And you click the ^UAdvanced^u tab.
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By default, Access specifies ^UNo Locks^u as the default record-locking strategy.
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If you select ^UEdited Record^u, Access locks records while you are editing them.
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If you select ^UAll Records^u, Access locks all the records in the datasheet you are working on while you have it open.
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If you select either ^UEdited^u ^URecord^u or ^UAll Records^u while you are working on a form or report, Access also locks the underlying records.
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Once you have selected a record-locking strategy, you click ^UOK^u.
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When you are editing a shared database, Access helps you to keep track of the status of records as you edit them.
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Suppose you are editing your Products table.
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When you click a record, the record selector usually displays an arrow.
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But if the record has been locked by another user, the record selector displays a "locked" symbol, and you are prevented from changing the record.
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When you are editing a record, the "editing" symbol is displayed.
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As long as this symbol is displayed, other users cannot see the changes you have made, or edit the record if you have locked it.
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If you and other people on your network use the No Locks strategy, editing conflicts between users can occur.
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Suppose you are editing an unlocked record, but another user saves a conflicting change before you finish editing.
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When you try to save your changes, Access tells you that a conflict has occurred and allows you to
ò save the record and overwrite the change made by
the other user
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ò copy your changes to the Clipboard so that you can
paste them in later
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ò ignore your changes and keep the changes made
by the other user
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When you are working with a shared database, other users could be changing data while you are viewing it.
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To update all the records on a datasheet, you select ^URecords - Refresh^u.
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As you can see, all the changes that have been made by other users are now displayed.
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Sometimes you only want to share the tables in a database, and allow users to create their own forms, reports, and macros.
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Access allows you to split a database into two files.
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One file contains a ^Rback-end^r database that includes only the tables.
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And the other contains a database that includes the queries, forms, reports, and macros, and is ^Rlinked^r to the back-end database.
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If you share the back-end database, then users can use copies of the other database to create forms, reports, and macros on their own computers.
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Sharing only the tables in a database also improves performance because less data is sent across the network.
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To split a database using this feature, select ^UTools - Add-Ins - Database Splitter^u.
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If the Database Splitter Wizard has not been installed, you need to run the Setup program and choose to add ^UAdvanced Wizards^u.
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Suppose you want to share the tables in your Sales database, but allow users to create their own forms and reports based on the data.
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A Sales back-end database has been created.
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The Sales database now contains tables that are linked to the Sales back-end database.
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When you replicate a database, you create copies of it - called ^Rreplicas^r.
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You can distribute replicas so that different users can work on their own copies of the database.
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You can also maintain a replica on your laptop computer so that you can work with the database even when you aren't connected to your network.
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Replication can be used to reduce network traffic.
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If users are given replicas, then they don't need to access a database over the network.
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Replication can also be used to back up a database.
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Replicating a database creates a ^Rreplica^r ^Rset^r.
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A replica set consists of replicas and one ^RDesign^r ^RMaster^r.
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A Design Master contains the same data as the other replicas in a set.
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But it is the only replica in which you can change the structure of the database.
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You ^Rsynchronize^r a replica to update it so that it contains the same data as another replica in the set.
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You can synchronize replicas with the Design Master to distribute changes to the structure of the database.
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Suppose you want to replicate your Sales database.
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You select ^UTools - Replication^u.
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And then you choose ^UCreate Replica^u.
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You click ^UYes^u to close the database.
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Access asks you whether you want to create a backup of the database.
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It's a good idea to create a backup because special tables, columns, and properties are added to a database when it is converted into a Design Master.
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You click ^UYes^u to create a backup.
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The Location of New Replica dialog box allows you to choose the folder into which you want to place the new replica.
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In this example you don't need to select a new folder, so you just click ^UOK^u.
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Access tells you that a Design Master and a replica have been created.
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You now click ^UOK^u.
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Access displays the new Design Master.
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The circles beside the table icons indicate that the tables are replicated objects.
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To open the replica, you click the ^UOpen Database^u button.
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You click the file that contains the replica.
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And then you click ^UOpen^u.
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You can now work with the replica as if it were any other database - although you cannot change the database's structure.
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You can create new objects - such as tables and forms - for the replica.
But these ^Rlocal^r ^Robjects^r cannot be synchronized with other replica set members.
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Suppose you want to create another replica for the replica set.
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You select ^UTools - Replication -^u ^UCreate Replica^u.
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And you click ^UOK^u.
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Access tells you that a new replica has been created.
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A new Design Master was not created because the replica set already contains a Design Master.
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You now click ^UYes^u to close and reopen the database.
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To work with a replica on your laptop, you can replicate a database using the Briefcase.
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You may need to run the Setup program and add ^UMicrosoft Briefcase^u ^UReplication^u before you can replicate a database using the Briefcase.
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Suppose you want to create a replica of your Sales database.
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You first find the file that contains the database in Windows Explorer or NT Explorer.
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Then you drag the file to the ^UMy Briefcase^u icon.
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You click ^UYes^u to continue.
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And you click ^UYes^u to create a backup of the database.
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Access allows you to specify which replica you want to be the Design Master.
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In this example, we'll leave the original copy as the Design Master.
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Next you click ^UOK^u.
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To view the contents of your Briefcase you double-click the ^UMy Briefcase^u icon.
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As you can see, your Briefcase now contains a replica of the Sales database.
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You can work on the database on your laptop, and later synchronize the replica with the Design Master.
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Synchronization is the process of updating two members of a replica set.
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When you synchronize two replicas, the changes made to each replica are applied to the other replica.
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If changes have been made that conflict with each other, Access provides tools for resolving these conflicts.
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Suppose you have replicated your Sales database and have made changes to both the Design Master and the Replica of Sales database.
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You now want to synchronize the two databases.
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You first open one of the databases - the Replica of Sales database in this example.
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And you select ^UTools -^u ^UReplication - Synchronize Now^u.
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If the path and filename of the database with which you want to synchronize is not displayed at the Synchronize With field, you type these in the field.
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If you don't know the path, you can click ^UBrowse^u to search for the file.
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If you want to convert the current database into the Design Master, you check the ^UMake ^Bx^b^u ^Uthe Design Master^u checkbox.
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But in this example we'll leave the checkbox unchecked.
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Next you click ^UOK^u.
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In this example, conflicting changes have been made to the two databases.
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You click ^UYes^u to resolve the conflict.
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The Resolve Replication Conflicts dialog box displays the location of the conflict.
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You click ^UResolve Conflicts^u.
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Access displays the existing record and the record on the other database that conflicts with it.
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In this example, conflicting addresses have been entered.
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If you want to replace the existing record with the conflicting record on the other database, you click ^UOverwrite^u ^Uwith Conflict Record^u.
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But in this example you click ^UKeep Existing Record^u.
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You click ^UYes^u.
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Then you click ^UOK^u.
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And you click ^UClose^u.
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If you now open the ^UCustomers^u table, you can see that the existing record was retained.
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The record has also overwritten the conflicting record in the database with which you were synchronizing.
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You can synchronize a replica that you created using your Briefcase with the original database.
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You click the file in My Briefcase and select ^UUpdate Selection^u from the ^UBriefcase^u menu.
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Suppose you have created a replica of your Sales database using your Briefcase.
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You have changed the replica on your laptop, and now you want to synchronize it with the original database.
