As a caveat to this question I am a beginner Access 2016 programmer of 2 months, but believe I have some intermediate to relatively advanced knowledge of the software as it's just about all I've been doing at work the last two months. I also realize now that I'm asking for trouble using hyperlinked fields as most people believe they're more hassle than they're worth (at least in older Access versions, it's surprisingly a little difficult to find Access 2016 information and opinions in 2018.. at least for me cause I'm apparently incapable of using "the google machine" properly), but I'm in a little too deep now.
At the moment I am trying to deploy a new database system but have run into some issues when testing. After turning my .accdb file into a .accde file the command to "Edit Hyperlink..." vanishes entirely from the shortcut menu when right-clicking. My employer would really like this functionality to be present in the final product, as he wants to display the file name but link to the file location in a shared network drive. I also need document control at his small company to be able to edit the hyperlinks but don't want them using an .accdb file that they could inadvertently make design changes to, or god knows what.
I have attempted to make a custom shortcut menu using this VBA module, which is executed by an AutoExec Macro, running upon opening the database.
Public Function CreateCustomRightClickMenu()
Const msoBarPopup As Long = 5, msoControlButton As Long = 1
' Create a shortcut menu named "CustomRightClickMenu"
With Application.CommandBars
With .Add(name:="CustomRightClickMenu", Position:=msoBarPopup, MenuBar:=False, Temporary:=True)
' Add cut command
.Controls.Add type:=msoControlButton, id:=21
' Add copy command
.Controls.Add type:=msoControlButton, id:=19
' Add paste command
.Controls.Add type:=msoControlButton, id:=22
' Add hyperlink command.
.Controls.Add type:=msoControlButton, id:=1576
' Add edit hyperlink command.
.Controls.Add type:=msoControlButton, id:=1577
End With
End With
End Function
I can get this function to work just fine in the .accde file, but the "Edit Hyperlink..." command is still unusable - it's greyed out. Is there some way to override this?
The only information I could find as to why this is the case is because a compiled .accde file restricts all design tools. I thought this explanation was rather... lackluster. Editing hyperlinks constitutes as a design tool? How would a hyperlinked field ever be advantageous then, in an automated system? And by automated I mean one that can run freely without a DBA sitting in some back-end file all day and updating the file's address lying beneath the display text. I will be on the opposite end of the country in a month and a half and will not be able to dip my toes in the back-end anymore so to speak.
Additionally, I saw many solutions for this problem in earlier versions of Access, but not in 2016. So my question is, what is it about the 2016 version in particular that is making this so difficult?
Or, can this be done at all?
Alternatively I've thought about using attachments and was assured that they don't bloat your system because Access will compress the files. After testing this I'm relatively sure it's not the case. I attached one 900kb .pdf file to 3 separate records in a database copy, and the .accdb file's size increased ~2700kb, as is to be expected. Compact and Repair had no effect on the final file size (3,974kb). 900kb files weren't realistic for my system though, and if my math is correct I should be able to store about 11,000-13,000 records in a 2GB Access database if I have 3 50kb files per record, subtracting 1000-2000 to account for the space of my access objects. Is this a realistic calculation, and what problems will I run into if I try and go this route?
EDIT: After briefly glancing over this webpage yesterday:
https://codekabinett.com/rdumps.php?Lang=2&targetDoc=access-hyperlink-data-type
I thought about it some more and realized I could just have our Doc control enter hyperlinks in the format "DisplayText#FileFullPathway#" ignoring sub address and scroll tip text.
And so far so good.
Then something interesting happened. I sent out a beta .accde file for DC to play with today, and the Edit Hyperlink... tool was magically available when I was getting her to test something unrelated (yesterday on her same machine the command either wouldn't be there, or if I had the CustomMenu set-up then the command was greyed out). I had deleted my custom menu from the entire database, no VBA module exists for anything menu related and the form's ShortcutMenu property is now blank. You'd think I'd be relieved but this is bothering me even more now - if I didn't enable it who did, and how come it wasn't there yesterday prior to having wasted all this time coming up with a workaround? Maybe I'm supposed to have that menu command and it was just bugged yesterday, but my travels through the Googlesphere yesterday suggest otherwise. This is driving me bonkers. For now my problem is resolved but I'd still like to know what's happening here.
Related
I am building an application that connects to a mysql database. I set up the data connections and data source (data set) and have begun working on development, going back and forth between adding tables and views to the database and adding forms and components to the application.
I have up to now used the "Configure Data Source with Wizard" wizard to refresh the dataset in the application. Sometimes it takes a couple click throughs to get it to fully load the changes, but that's not the end of the world.
Today, without me knowingly changing anything, when I click on the wizard button, the frame of the wizard opens and closes instantly.
My data is accessible, and the parts of the application already developed work just fine, but I don't know how to add new tables and views to my project. My worry is that something went screwy in one of the auto generated dbDataSet.* files.
I'm happy to provide more information if that will help.
To answer my own question for whomever comes here next:
I came across this solution:
https://stackoverflow.com/a/4749044/7640114
It links to a microsoft.com page that is no longer available, but copies the relevant information. Finding the corresponding files is not hard, but knowing what the wrong Provider is may not be so simple.
Mostly because of a lack of patience, I just went with the second option and deleted the entire folder, which may have been overkill. It worked, and I have access to the wizard again and can continue development, but it also wiped out my workspace layout which I now have to rebuild from my memory.
Win some/loose some. In the end, I suggest being more delicate and removing lines of code from DefaultView.SEView first, and then moving on to trying to delete the file and the folder if nessasary.
When working with an Access .accdb, every time I open the file, I see that the 'date modified' in the filesystem changes to now. This makes me nervous. I want it to stop.
I can't be the only person who has ever saved a working db, and opened it a few weeks or months later to an error. Sure, I probably have backups, and backups to my backups, and table data saved separately from my code, and version history taking up multiple gigabytes of the filesystem or in emails or where ever... but it still makes my heart jump a little whenever I see the date modified update on open, when I haven't touched the DB in some time.
Have I flipped a switch somewhere that makes it do this? Is this expected behavior? How can I stop it?
To replicate this, create a new accdb, save and close. Put something in it, nothing, or close it only a second after creating it. Open an windows explorer for the directory the accdb is saved in, and note the date modified value. Open the file at least a minute after the displayed date modified file. alt-tab back to the explorer window, and you see the date modified has changed.
That's the default behaviour, even with a native Access MDB file. They don't work like a normal file that you have to explicitly modify to update the date - it does some things when you open it up, whether you want it to or not.
Just did a quick test - if you set the database file to read-only, it doesn't update itself.
I construct my MS Access Applications into front end and a back end. The Front end database is made up of all the the application objects like the Queries, Forms, Reports, and Modules. The back end database is made up of the tables and links to other data sources.
Many people consider this a Microsoft Access Generally Accepted Best Practice.
So much so that Microsoft includes a Wizard to do the split for you. Shown here
10 Reasons to Split an Access Database
Once the database has been split, It makes is a whole lot more manageable. The Front End can be marked read-only. The Back End remains writable.
I have a front-end Access 2007 apllication which talks to MySql server.
I want to have a feature where the application on the user's computer can detect that there is a new version on the network (which is not difficult) and download the latest version to the local drive and launch it.
Does anybody has any knowledge or exprience how this can be done?
Thanks
Do you actually need to find out if there is a newer version?
We have a similar setup as well, and we just copy the frontend and all related files every time someone starts the application.
Our users don't start Access or the frontend itself. They actually start a batch file which looks something like this:
#echo off
xcopy x:\soft\frontend.mde c:\app\ /Y
c:\app\frontend.mde
When we started writing our app, we thought about auto-updating as well and decided that just copying everything everytime is enough.
We have enough bandwidth, so the copying doesn't create any performance problems (with about 200 users).
Plus, it makes some things easier for me as a developer when I can be sure that each time the application is started, the frontend is overwritten anyway.
I don't have to care about auto-compacting the frontend when it's closed (and users complaining that closing the app takes too long...), and I don't have to deal with corrupted frontends after crashes.
#Lumis - concerning the custom icon:
Ok, maybe I should have made this more clear. There is only one batch file, and it's in the same network folder as the frontend.
The users just have links on their desktops which all point to the same batch file in the network folder.
This means that:
future changes to the batch file are easy, because it's only one single
file in one central place
we can change the icon, because
what the user sees is a normal Windows link
(By the way, we did not change the icon. Our app is for internal use only, and I'm working in a manufacturing company, which means that all but very few users are absolutely non-technical and couldn't care less about the icon, as long as it's the same on all machines and they know how it looks like so they can find it quickly on their desktop...)
Tony Toews has one: Access Auto FE Updater
It appears to be free, but I'm not 100% sure.
Lumis's option is solid, however if you want to check the version and only copy the database when their is a new version, have a 'Version' field in a back end table, and a 'Version' constant in a front end module. Keep these in sync with each new production release. Compare the table version against the version in the module when the main form of the front end database opens.
If they don't match, have the database close, but have the database call a batch file as the last bit of code to run as it's closing. The database should finish closing before the batch file begins it's copy process. If needed, place a minor delay in the batch file code just to be sure there are no file locking issues.
I have created an MS Access 2003 application, set up as a split front-end/back-end configuration, with a user group of about five people. The front end .mdb sits on a network file server, and it contains all the queries, forms, reports, and VBA code, plus links to all the tables in the back end .mdb and some links to ODBC data sources like an AS/400. The back end sits on the same network file server, and it just has the table data in it.
This was working well until I "went live" and my handful of users started coming up with enhancement requests, bug reports, etc. I have been rolling out new code by developing/testing in my own copy of the front-end .mdb in another network folder (which is linked to the same back-end .mdb), then posting my completed file in a "come-and-get-it" folder, alerting the users, and they go copy/paste the new front-end file to their own folders on the network. This way, each user can update their front end when they're at a 'stopping point' without having to boot everyone out at once.
I've found that when I'm developing now, sometimes Access becomes extremely slow. Like, when I am developing a form and attempt to click a drop-down on the properties box, the drop-down arrow will push in, but it will take a few seconds before the list of options appears. Or there's tons of lag in selecting & moving controls on a form. Or lots of keyboard lag.
Then, at other times, there's no lag at all.
I'm wondering if it's because I'm linked to the same back end as the other users. I did make a reasonable effort to set up the queries, forms, reports etc. with minimal record locking, if any at all, depending on the need. But I may have missed something, or perhaps there is some other performance issue I need to address.
But I'm wondering if there is an even better way for me to set up my own development back-end .mdb, so I can be testing my code on "safe" data instead of the same live data as the rest of the users. I'm afraid that it's only a matter of time before I corrupt some data, probably at the worst possible moment.
Obviously, I could just set up a separate back-end .mdb and manually reconfigure the table links in the front end every time, using the Linked Table Manager. But I'm hoping there is a more elegant solution than that.
And I'm wondering if there are any other performance issues I should be considering in this multi-user, split database configuration.
EDIT: I should have added that I'm stuck with MS Access (not MS-SQL or any other "real" back end); for more details see my comment to this post.
If all your users are sharing the front end, that's THE WRONG CONFIGURATION.
Each user should have an individual copy of the front end. Sharing a front end is guaranteed to lead to frequent corruption of the shared front end, as well as odd corruptions of forms and modules in the front end.
It's not clear to me how you could be developing in the same copy of the front end that the end users are using, since starting with A2000, that is prohibited (because of the "monolithic save model," where the entire VBA project is stored in a single BLOB field in a single record in one of the system tables).
I really don't think the problems are caused by using the production data (though it's likely not a good idea to develop against production data, as others have said). I think they are caused by poor coding practices and lack of maintainance of your front end code.
turn off COMPILE ON DEMAND in the VBE options.
make sure you require OPTION EXPLICIT.
compile your code frequently, after every few lines of code -- to make this easy, add the COMPILE button to your VBE toolbar (while I'm at it, I also add the CALL STACK button).
periodically make a backup of your front end and decompile and recompile the code. This is accomplished by launching Access with the /decompile switch, opening your front end, closing Access, opening your front end with Access (with the SHIFT key held down to bypass the startup code), then compacting the decompiled front end (with the SHIFT key held down), then compiling the whole project and compacting one last time. You should do this before any major code release.
A few other thoughts:
you don't say if it's a Windows server. Linux servers accessed over SAMBA have exhibited problems in the past (though some people swear by them and say they're vastly faster than Windows servers), and historically Novell servers have needed to have settings tweaked to enable Jet files to be reliably edited. There are also some settings (like OPLOCKS) that can be adjusted on a Windows server to make things work better.
store your Jet MDBs in shares with short paths. \Server\Data\MyProject\MyReallyLongFolderName\Access\Databases\ is going to be much slower reading data than \Server\Databases. This really makes a huge difference.
linked tables store metadata that can become outdated. There are two easy steps and one drastic one to be taken to fix it. First, compact the back end, and then compact the front end. That's the easy one. If that doesn't help, completely delete the links and recreate them from scratch.
you might also consider distributing an MDE to your end users instead of an MDB, as it cannot uncompile (which an MDB can).
see Tony Toews's Performance FAQ for other generalized performance information.
1) Relink Access tables from code
http://www.mvps.org/access/tables/tbl0009.htm
Once I'm ready to publish a new MDE to the users I relink the tables, make the MDE and copy the MDE to the server.
2) I specifically created the free Auto FE Updater utility so that I could make changes to the FE MDE as often as I wanted and be quite confident that the next time someone went to run the app that it would pull in the latest version. For more info on the errors or the Auto FE Updater utility see the free Auto FE Updater utility at http://www.granite.ab.ca/access/autofe.htm at my website to keep the FE on each PC up to date.
3) Now when working on site at a clients I make the updates to the table structure after hours when everyone is out of the system. See HOW TO: Detect User Idle Time or Inactivity in Access 2000 (Q210297) http://support.microsoft.com/?kbid=210297 ACC: How to Detect User Idle Time or Inactivity (Q128814) http://support.microsoft.com/?kbid=128814
However we found that the code which runs on the timer event must be disabled for the programmers. Otherwise weird things start happening when you're editing code.
Also print preview would sometimes not allow the users to run a menu item to export the report to Excel or others. So you had to right click on the Previewed report to get some type of internal focus back on the report so they could then export it. This was also helped by extending the timer to five minutes.
The downside to extending the timer to five minutes was if a person stays in the same form and at the same control for considerable parts of the day, ie someone doing the same inquiries, the routine didn't realize that they had actually done something. I'll be putting in some logic sometime to reset this timer whenever they do something in the program.
4) In reference to another person commenting about scripts and such to update the schema see Compare'Em http://home.gci.net/~mike-noel/CompareEM-LITE/CompareEM.htm. While it has its quirks it does create the VBA code to update tables, fields, indexes and relationships.
Use VBA to unlink and re-link your tables to the new target when switching from dev to prod. It's been to many years for me to remember the syntax--I just know the function was simple to write.
Or use MS-Access to talk to MS-Access through ODBC, or some other data connection that lives outside of the client mdb.
As with all file base databases, you will eventually run into problems with peak usage or when you go over a small magical number somewhere between 2 and 30.
Also, Access tends to corrupt frequently, so backup, compact and repair need to be done on an frequent basis. 3rd party tools used to exist to automate this task.
As far as performance goes, the data is being processed client side, so you might want to use something like netmeter to watch how much data is going over the wire. The same principle about indexing and avoiding table scans apply to file base dbs as well.
Many good suggestions from other people. Here's my 2 millicents worth. My backend data is on server accessed through a Drive mapping. In my case, the Y drive. Production users get the mapping through a login script using active directory. Then the following scenarios are easily done by batch file:
Develop against local computer by doing a subst command in a batch file
run reports against last nights data by pointing Y to the backup server (read only)
run reports against end of month data by pointing to the right directory
test against specialized scenarios by keeping a special directory
In my environment (average 5 simultaneous users, 1000's of rows, not 10,000's.) corruption has occurred, but it's rare and manageable. Only once in the last several years have we resorted to the previous days backup. We use SQL Server for our higher volume stuff, but it's not as convenient to develop against, probably because we don't have a SQL admin on site.
You might also find some of the answers to this question (how to extract schemas from access) to be useful as well. Once you've extracted a schema using one of the techniques that were suggested you gain a whole range of new options like the ability to use source control on the schemas, as well as being able to easily build "clean" testing environments.
Edit to respond to comment:
There's no easy way to source control an Access database in it's native format, but schema files are just text files like any other. Hence, you can check them in and out of the source control software of your choice for easy version control/rollbacks.
Or course, it relies on you having a series of scripts set up to re-build your database from the schema. Once you do, it's normally fairly trivial to create an option/alternative version that rebuilds it in a different location, allowing you to build test environments from any previous committed version of the schema. I hope that clarifies a bit!
If you want to update the back end MDB schema automatically when you release a new FE to the clients then see Compare'Em http://home.gci.net/~mike-noel/CompareEM-LITE/CompareEM.htm will happily generate the VBA code need to recreate an MDB. Or the code to create the differences between two MDBs so you can do a version upgrade of the already existing BE MDB. It's a bit quirky but works.
I use it all the time.
You need to understand that a shared mdb file for the data is not a robust solution. Microsoft would suggest that SQL Server or some other server based database would be a far better solution and would allow you to use the same access front end. The migration wizard would help you make the changeover if you wanted to go that way.
As another uses pointed out, corruption will occur. It is simply a question of how often, not if.
To understand the performance issues you need to understand that to the server the mdb file with the data in it is simply that, a file. Since no code runs on the server, the server does not understand transactions, record locking etc. It simply knows that there is a file that a bunch of people are trying to read and write simultaniously.
With a database system such as SQL Server, Oracle, DB2. MySQL etc. the database program runs on the server and looks to the server like a single program accessing the database file. It is the database program (running on the server) that handles record locking, transactions, concurrency, logging, data backup/recovery and all the other nice things one wants from a database.
Since a database program designed to run on the server is designed to do that and only that, it can do it far better and more efficently that a program like Access reading an writing a shared file (mdb).
There are two rules for developing against live data
The first rule is . . . never develop
against live data. Not ever.
The second rule is . . .never develop
against live data. Not ever.
You can programatically change the bindings for linked tables, so you can write a macro to change your links when you're deploying a new version.
The application is slow because it's MS Access, and it doesn't like many concurrent users (where many is any number > 1).
I'm working on a MS Access database. I've made some changes to one of the modules. I want to go out for lunch, but when I try closing the database, I get the following message:
"You do not have exclusive access to the database. Your design changes cannot be saved at this time. Do you want to close without saving your changes?"
I'm pretty sure nobody else on the network has the database file open, and I don't have any other Access databases open. I'm probably missing something obvious, but would really appreciated some help!
Update:
In the end I copied all the code, closed the database without saving, re-opened it and pasted the code back in. I was then able to save the database. I'm not sure if this was a one off, but I'll report back if it happens again.
If you're sure no one else is in the db but you, it's an additional connection to your db from your own pc. You can verify this with the LDB viewer, downloadable in the free JetUtils.exe download from Microsoft:
http://support.microsoft.com/kb/176670
Look through your code and check if you have two separate database objects in the default workspace or another database object in a separate workspace. That will cause this problem.
To fix it, make sure the database objects are set to nothing before they go out of scope, and if you opened the database object in code, you also need to close it before setting the database object to nothing.
=============================================
Update in August 2022:
The MS link above no longer works. The document remains available on Archive.org, but is outdated. A document that appears to provide the current version of its information is at:
https://learn.microsoft.com/en-us/office/troubleshoot/access/determine-who-is-logged-on-to-database
This provides VBA code for a sub to obtain a list of users. The writer of this update has tested that code successfully in Access 2019.
If you close the database and are sure nobody else has it opened, check to see if there is a .ldb file (it will have the same name as your database file). If the file is there, then there is a good chance it is still in use.
Is it being access by a service, like a website?
You could copy the database to another sub-directory and make your changes. If that doesn't work, I will have to look that up. Of course there is always the database tool, "repair and compress database..."
Is the file located on a file server? If so check to see if any users have a file handle to it.
If it still doesn't work, update your post with your new information and we'll go further.
UPDATE (9/26):
Another thing I do when having strange issues with access databases with contain vba code is decompile. I don't know if this is documented yet, I haven't looked in years, but it's was (at least) an undocumented switch to msaccess.
From a cmd line:
change directory to where msaccess.exe is located.
Run the following command
msaccess \path to access file\databasefile.mdb /decompile
usually runs very quick then opens the database. Open any module and compile.
Doesn't always work, but sometimes can remove strange happenings.
Did you ever trying to copy the database to another directory and making your edits? That should of worked; you could then rename the original and copy the file back.
Anyway, I am glad you are working again.
If even a word mail merge is linked to the access database, that counts as an access connection.
Very simple.
Close all of your MSaccess files.
Open task manager (by right click on task bar).
Select Processes tab in that.
If the list has a msaccess*32 process close that by clicking on End Process.
This worked for me. I think it closes all the recordset which we have not closed in the codes or which is closed forcefully.