As an overview, a big issue with multiple users is editing the same data and tables.
The issue needs to be addressed differently depending on what backend you are accessing the data from. Today we’ll start the discussion with Access file backends.
Access files handle this with lock files and different locking mechanisms like Optimistic, Pessimistic. Basically, how you want Access to behave when two users are moving to the same table or record. Copilot seemed to give a good overview, so I’ll share for your benefit:
🔐 Locking Mechanisms in Microsoft Access for Multi-User Editing
Microsoft Access supports multiple users editing data simultaneously, but it uses specific locking mechanisms to maintain data integrity and prevent conflicts. Here’s a breakdown of how it works and best practices for managing multi-user environments.
🧩 Types of Locking in Microsoft Access
1. Record-Level Locking
- Locks only the specific record being edited.
- Other users can read the record but cannot edit it until the lock is released.
- Enabled via the “Open Databases Using Record-Level Locking” option in Access settings.
2. Page-Level Locking
- Locks a 4KB page of data, which may include multiple records.
- Can cause more contention in multi-user environments.
- Typically used in older versions or when record-level locking is disabled.
3. Pessimistic Locking
- Locks a record as soon as a user starts editing it.
- Prevents others from editing the same record until changes are saved or canceled.
- Ideal when data conflicts are likely.
4. Optimistic Locking
- No lock is placed during editing.
- Locking occurs only when the user attempts to save changes.
- If another user has modified the record, a write conflict error appears.
📁 Locking Files: .LDB and .LACCDB
When an Access database is opened, a temporary locking file is created:
.ldbfor.mdbfiles.laccdbfor.accdbfiles
These files track:
- Who has the database open
- Which records are currently locked
The locking file is automatically deleted when the last user closes the database.
✅ Best Practices for Multi-User Access
- Split the Database
- Front-end: Forms, queries, reports, and VBA code (stored on each user’s machine).
- Back-end: Tables and data (stored on a shared network drive).
- Improves performance and reduces risk of corruption.
- Enable Record-Level Locking
- Minimizes interference between users editing different records.
- Design for Minimal Overlap
- Structure workflows to reduce the chance of users editing the same records simultaneously.
- Compact and Repair Regularly
- Helps maintain database performance and integrity.
By understanding and configuring these locking mechanisms, you can ensure smoother collaboration and fewer data conflicts in your Microsoft Access environment.