When more than one user is accessing the same data at the same time it is known as?
AppSheet apps allow multiple users to add, update, and delete data concurrently. This leads to the natural question -- how do we deal with multiple people updating the same data at the same time? The simple rule is that the last writer wins. There are three cases during client sync when "the last writer wins" conflict resolution strategy may be used. If the user adds a row when a row with the same key already exists,
then that row is updated with the data contained in the second client's add request. When this occurs, the Audit History record for the second Add operation will include the This can sometimes occur if a single client submits the same add request multiple times. For example, the client might submit the add request and then lose network connectivity before the server can respond to the original add request. This leaves the client uncertain if the add request was received and processed by the server. In this case, the client resubmits the add request when network connectivity is later restored. The server attempts to detect and properly respond to duplicate client requests. The server remembers the most recent request from each client for up to 24 hours. If the client resubmits the same request again, the server detects the duplicate request and responds with the same answer it would have returned for the original request. By remembering the most recent request and response for each client, the server attempts to handle duplicate client requests gracefully. It avoids performing the client's add request twice. If the client loses network connectivity for longer than 24 hours, the server may no longer remember the original client request. If the client resubmits the add request thereafter, the server will attempt to perform the add request for a second
time. When it performs the add request and detects that the record already exists, it will include the If your application contains automation workflow rules that are triggered by add operations, those rules will be triggered again when the second client add request is submitted more than 24 hours after the first client add request. You can
detect when this has occurred by looking at the Audit History DeleteDeletedRecord on deleteIf the user deletes a row but no row with that key exists, then that change is ignored. When this occurs, the Audit History record for the delete operation will include the UpdateDeletedRecord on updateIf the user edits a row but no row with that key exists, then that change is ignored because clearly some other user explicitly deleted it first. When
this occurs, the Audit History record for the edit operation will include the Was this helpful? How can we improve it? What is multiple user access?Multi-user software is computer software that allows access by multiple users of a computer. Time-sharing systems are multi-user systems. Most batch processing systems for mainframe computers may also be considered "multi-user", to avoid leaving the CPU idle while it waits for I/O operations to complete.
Can more than one person be in Access database at the same time?Share a single database
In this method, the database file is stored on a shared network drive, and all users share the database file simultaneously. Some limitations include reliability and availability if there are multiple simultaneous users changing data since all database objects are shared.
What is simultaneous access to data?It is possible that two or more utilities or programs could be accessing the same file at the same time, making changes. For example, two people could be using ed to edit the same file at the same time.
What problem can occur when a database is processed by more than one user?When a database is processed by more than one user, there is a chance that one user's work may interfere with the work of another user. This problem is discussed in detail in Chapter Nine: Managing Multiuser Databases.
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