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First of all, I'm not a DB expert .. so I'm not sure if my terminology or anything is correct here, but if you can bear with me I hope you'll get the idea.
I have a SQL Azure database which powers a social network. Millions of transactions occur every day from very simple ones to complex SELECTS which sort through tens of thousands of users based on distance etc.
My user numbers grow daily and I know (believe) that at some point I'll need to implement sharding, or make use of SQL Azure Federation to keep my app up and running due to 1 SQL Azure having limited resources ... but my question is, how do I figure out when I'm going to need to do this?
I know that when I start to use too much resources, my queries will be throttled ... but for all I know this could start happening tomorrow, or be years away.
If I know I'm hitting 80% of what I'm allowed to, then I know I need to prioritise a solution to help me scale things out, but if I'm only using 10% then I know I can put this on the back-burner and deal with it later.
I can't find any way, or even mention, of how to measure this?
Any suggestions?
Thanks,
Steven
I don't know of any inbuilt way to measure this. If somebody does then I would be very interested to hear about it.
However there is a great library from the Microsoft AppFabric CAT Best Practices Team which is a transient fault handling framework. See here
This does a number of things including handling retry logic for opening connections and running queries. You could use that but extend it slightly to log when you were being throttled by SQL Azure.
This probably wont give you as much warning as you want, but will help you know when you are getting closer to the limit. If you combined this approach together with some kind of application / database stress testing then you can find your limits now before your real usage gets there.
Based on the numbers you have given I would definitely start looking at sharding now.
I would recommend you read the article below if you haven't done so; it contains interesting information about the underlying reasons for SQL Azure throttling conditions. Understanding what is being monitored for throttling can help you figure out why your database is being throttled.
Technet Article: SQL Azure Connection Management
Thank you for mentioning the Enzo library by the way (disclaimer: I wrote it)!
However understanding the reason of the throttling would be my first recommendation because depending on the reason, sharding may or may not help you. For example, if the issue of the thottling is excessive locks, sharding may indeed reduce locks to a single database, but it could come back and bite you at a later time.
Thank you
Herve
best practices to fight throttling 1) keep queries as short as possible 2) run workloads in batches 3) employ retry mechanisms.
I would also like to point you to couple of resources.
1) sql azure throttling and decoding reason codes: http://msdn.microsoft.com/en-us/library/ff394106.aspx#throttling
2) http://geekswithblogs.net/hroggero/archive/2011/05/26/cloud-lesson-learned-exponential-backoff.aspx
I have a question, just looking for suggestions here.
So, my application is 'modernizing' a desktop application by converting it to the web, with an ICEFaces UI and server side written in Java. However, they are keeping around the same Oracle database, which at current count has about 700-900 tables and probably a billion total records in the tables. Some individual tables have 250 million rows, many have over 25 million.
Needless to say, the database is not scaling well. As a result, the performance of the application is looking to be abysmal. The architects / decision makers-that-be have all either refused or are unwilling to restructure the persistence. So, basically we are putting a fresh coat of paint on a functional desktop application that currently serves most user needs and does so with relative ease. The actual database performance is pretty slow in the desktop app now. The quick performance I referred to earlier was non-database related stuff (sorry I misspoke there). I am having trouble sleeping at night thinking of how poorly this application is going to perform and how difficult it is going to be for everyday users to do their job.
So, my question is, what options do I have to mitigate this impending disaster? Is there some type of intermediate layer I can put in between the database and the Java code to speed up performance while at the same time keeping the database structure intact? Caching is obviously an option, but I don't see that as being a cure-all. Is it possible to layer a NoSQL DB in between or something?
I don't understand how to reconcile two things you said.
Needless to say, the database is not scaling well
and
currently serves most user needs and does so with relative ease and quick performance.
You don't say you are adding new users or new function, just making the same function accessible via a web interface.
So why is there a problem. Your Web App will be doing more or less the same database work as before.
In fact introducing a web tier could well give new caching opportunities so reducing the work the DB is doing.
If your early pieces of web app development are showing poor performance then I would start by trying to understand how the queries you are doing in the web app differ from those done by the existing app. Is it possible that you are using some tooling which is taking a somewhat naive approach to generating queries?
If the current app performs well and your new java app doesn't, the problem is not in the database layer, but in your application layer. If performance is as bad as you say, they should notice fairly early and have the option of going back to the Desktop application.
The DBA should be able to readily identify the additional workload on the database from your application. Assuming the logic hasn't changed it is unlikely to be doing more writes. It could be reads or it could be 'chattier' (moving the same amount of information but in smaller parcels). Chatty applications can use a lot of CPU. A lot of architects try to move processing from the database layer into the application layer because "work on the database is expensive" but actually make things worse due to the overhead of the "to-and-fro".
PS.
There's nothing 'bad' about having 250 million rows in a table. Generally you access a table through an index. There are typically 2 or 3 hops from the top of an index to the bottom (and then one more to the table). I've got a 20 million row table with a BLEVEL of 2 and a 120+ million row table with a BLEVEL of 3.
Indexing means that you rarely hit more than a small proportion of your data blocks. The frequently used index blocks (and data blocks) get cached in the database server's memory. The DBA would be able to see if this memory area is too small for the workload (ie a lot of physical disk IO).
If your app is getting a lot of information that it doesn't really need, this can put pressure on the memory space. Don't be greedy. if you only need three columns from a row, don't grab the whole row.
What you describe is something that Oracle should be capable of handling very easily if you have the right equipment and database design. It should scale well if you get someone on your team who is a specialist in performance tuning large applications.
Redoing the database from scratch would cost a fortune and would introduce new bugs and the potential for loss of critical information is huge. It almost never is a better idea to rewrite the database at this point. Usually those kinds of projects fail miserably after costing the company thousands or even millions of dollars. Your architects made the right choice. Learn to accept that what you want isn't always the best way. The data is far more important to the company than the app. There are many reasons why people have learned not to try to redesign the database from scratch.
Now there are ways to improve database performance. First thing I would consider with a database this size is partioning the data. I would also consider archiving old data to a data warehouse and doing most reporting from that. Other things to consider would be improving your servers to higher performing models, profiling to find slowest running queries and individually fixing them, looking at indexing, updating statistics and indexes (not sure if this is what you do on Oracle, I'm a SLQ Server gal but your dbas would know). There are some good books on refactoring old legacy databases. The one below is not datbase specific.
http://www.amazon.com/Refactoring-Databases-Evolutionary-Database-Design/dp/0321293533/ref=sr_1_1?ie=UTF8&s=books&qid=1275577997&sr=8-1
There are also some good books on performance tuning (look for ones specific to Oracle, what works for SQL Server or mySQL is not what is best for Oracle)
Personally I would get those and read them from cover to cover before designing a plan for how you are going to fix the poor performance. I would also include the DBAs in all your planning, they know things that you do not about the database and why some things are designed the way they are.
If you have a lot of lookups that are for items not in the database you can reduce the number by using a bloom filter. Add everything in the database to the bloom filter then before you do a lookup check the bloom first. Only if the bloom reports it present do you need to bother the database. The bloom will result in false positives but you can design it to the 'size vs false positive' trade off that best suits you.
The strategy is used by Google in their big-table database and they have reported that it significantly improves performance.
http://en.wikipedia.org/wiki/Bloom_filter
Good luck, working on tasks you don't believe in is tough.
So you put a fresh coat of paint on a functional and quick desktop application and then the system becomes slow?
And then you say that "it is needless to say that the database isn't scaling well"?
I don't get it. I think that there is something wrong with your fresh coat of paint, not with the database.
Don't be put down by this sort of thing. See it as a challenge, rather than something to be losing sleep over! I know it's tempting as a programmer to want to rip everything out and start over again, but from a business perspective, it's just not always viable. For example, by using the same database, the business can continue to use the old application while the new one is being developed and switch over customers in groups, rather than having to switch everyone over at the same time.
As for what you can do about performance, it depends a lot on the usage pattern. Caching can help greatly with mostly read-only databases. Even with read/write database, it can still be a boon if correctly designed. A NoSQL database might help with write-heavy stuff, but it might also be more trouble than it's worth if the data has to end up in a regular database anyway.
In the end, it all depends greatly on your application's architecture and usage patterns.
Good luck!
Well without knowing too much about what kinds of queries that are mostly done (I would expact lookups to be more common) perhaps you should try caching first. And cache at different layers, at the layer before the app server if possible and of course what you suggested caching at the layer between the app server and the database.
Caching works well for read data and it might not be as bad as you think.
Have you looked at Terracotta ? They do have some caching and scaling stuff that might be relavant to you.
Take it as a challenge!
The way to 'mitigate this impending disaster' is to do what you should be doing anyway. If you follow best practices the pain of switching out your persistence layer at a later stage will be minimal.
Up until the time that you have valid performance benchmarks and identified bottlenecks in the system talk of performance is premature. In any case I would be surprised if many of the 'intermediate layer' strategies aren't already implemented at the database level.
If the database is legacy and enormous, then
1) it cannot be changed in a way that will change the interface, as this will break too many existing applications. Or, if you change the interface, this has to be coordinated with modifying multiple applications with associated testing.
2) If the issue is performance, then there are probably many changes that can be made to optimize the database without changing the interface.
3) Views can be used to maintain the existing interfaces while restructuring tables for more efficiency, or possibly to allow more efficient access in the future.
4) Standard database optimizations, such as performance analysis, indexing, caching can probably greatly increase efficiency and performance without changing the interface.
There's a lot more that can be done, but you get the idea. It can't really be updated in one single big change. Changes have to be incremental, or transparent to the applications that use it.
The database is PART of the application. Don't consider them to be separate, it isn't.
As developer, you need to be free to make schema changes as necessary, and suggest data changes to improve performance / functionality in production (for example archiving old data).
Your development system presumably does not have that much data, but has the exact same schema.
In order to do performance testing, you will need a system with the same hardware and same size data (same data if possible) as production. You should explain to management that performance testing is absolutely necessary as you feel the app isn't going to perform.
Of course making schema changes (adding / removing indexes, splitting tables out etc) may affect other parts of the system - which you should consider as parts of a SYSTEM - and hence do the necessary regression testing and fixing.
If you need to modify the database schema, and make changes to the desktop client accordingly, to make the web app perform, that is what you have to do - justify your design decision to the management.
I'm new to production level web development, so sorry if this is obvious. My site has a potential to have a sudden surge of (permanent) users and I'm wondering what happens if too many users sign up in a short period of time, causing the site to run slowly. Since development takes time, would it just be a case of adding more boxes to the server, or does the site have to be taken down for code improvement?
Thanks
Don't worry even very popular sites go through this. Coding well is always a plus, but sometimes even that is not enough. Twitter being an ideal example, they started their messaging on Ruby but had to move to Scala as they became more and more popular.
Since you say you are new, can I suggest getting yourself familiar with caching queries and caching static content? Learning about good indexing practices on SQL server should also be helpful in dealing with a large influx of users.
Both but code improvement would be the first to target. Writing code that will scale will help you out the most. You can throw more servers at it behind the scenes but you would have to do this less with well architected code that was designed for scalability.
Depends on the technologies your using and how the code you write is written.
Since you tagged sql-server, when it comes to databases in general, you are limited by your locking strategies and your replication architecture a lot of the time. How you design your database and put it into production has big impact. Things that have to happen in any type of serial manner are bottlenecks. Check your execution plans, watch and manage your indexes, and replicate and distribute your systems if you can.
The best way to understand your scalability limitations is through load testing and proper QA.
If you don't do it right, your users are sure to be unhappy when you start 503ing or timing out. :-)
If the site is developed in such a fashion that you can have multiple servers/data access layers, then scalibilty should not be an issue.
Create the app so that you can loadshed as required, and keep the code as flexible as possible.
But from past experiance. Performance tune once it is required. Write easily understandable and maintainable code, and fix performance issues as the occur.
The best advice I can give is to test your app and server before you go live, then you can see when you are likely to get problems and how bad they could be.
It is one thing to say 'it will go slow' but once you get past a certain point your app may crash or randomly give users error 500 pages.
Test with automatic scripts tools to stress the site and simulate sign-ups and random users visiting random pages.
If you have SSL make sure your tools simulate lots of different SSL connections rather than just different HTTP requests ( SSL handshakes take extra resources )
I'm part of a software development company where we do custom developed applications for our clients.
Our software uses MS SQL Server and we have encountered some customers which do not have a DBA on staff to manage the databases or if they do, they lack the necessary knowledge to perform their job adequately.
We are in the process of drafting a contract with one of those customers to provide development services for new functionality on our software during the next year, where they have an amount of hours available for customization of our software.
Now they want us to include also a quote for database administration services and the problem is that they are including a clause that says that those services will be provided only when they request it.
My first reaction is that db administration is an ongoing process and not something that they can call us once a month to come for a day or two. I'm talking about a central 1TB+ MSSql Cluster and 100 branch offices with MSSql Workgroup edition.
My question is for any suggestions on how I could argue that there must be a fixed amount of hours every month for dba work and not only when their management thinks they need it (which I’m guessing would only be when they have a problem).
PS: Maybe this will be closed as not programming related. But I'm a programmer and I have this problem. My work is software development but i don't want to lose this client and the only solution I can think of is to find a way for the client to understand the scope so we can hire a qualified DBA to provide them with the service they require.
Edit: We are in a Latin American country with clients in the Spanish speaking region. My guess is that in more developed countries there is a culture that knows how delicate the situation is.
This is definitely one of those 'you can lead a horse to water, but you can't make them drink' situations.
My recommendation here would be to quote the DBA services as hourly, and make the rate high enough that you can outsource the work if you decide you want to. When (not if) the SQL servers start to have problems, the firm is on the hook.
I would also recommend that you include in your quote a non-optional 2 hour database technology review once per year. This is your opportunity to say 'You spent XXX on database maintenance this year, most of which was spent fighting fires that could have been easily avoided if you had just spent XXXX/4 and hired a DBA. We care about you as a customer, and we want you to save money, so we really recommend that you commit to using a DBA to perform periodic preventative maintenance'.
I would also recommend that you categorize any support requests as having root cause b/c of database maintenance vs other causes. This will let you put a nice pie chart in front of the customer during their annual review (which they are going to pay you to perform). It is critical to manage the perception so they don't think your code is causing the problems. You might even go so far as to share these metrics (db related issue vs non-db related issue) with them on a quarterly basis.
Sometimes people need to experience pain before they change. The key is to not be in between the hammer and their thumb as they learn the lesson, and hourly quoted work is one way of doing this.
As a side note, this sort of question is of great interest to a large number of developers. I'd say that this sort of thing could impact a programmer's quality of life more than any algorithm or library question ever could. Thanks for asking it!
No DBA on a system that size is a disaster waiting to happen. If they don't understand that, they are not qualified to run a database that size. I'd recommend that they talk to other companies with similar sized databases and have them ask them about their DBAs and what they do for them, and if they think they could survive without them.
Perhaps the link below from MS SQL Tips could give you some good talking points. But people who aren't technical wont respond to a technical explanation of the necessity of good DBA you are likley going to have to work toward proving the cost of bad DBA. Work out the worst case scenarios and see how they feel about them. If you can make it seem like a good financial move (and I think we all know it is) it will be an easy sell.
http://www.mssqltips.com/tip.asp?tip=1278
I am having a real problem at work with a highly ingrained developer obsessed with ms access. Users moan about random crashes, locking errors, freeze's, the application slowing down (especially in 2007) but seem to be very resistant to moving it. Most of the time they blame the computer and can't be convinced it's the fact its a mdb sat on a network drive and nothing to do with the hardware sat in front of them which is brand new.
There is a front end vb program hanging off it but I don't think it would take more than a couple of weeks to adjust, infact I would probably re-write it as it has year on year messy code from a previous developer.
What are my best arguments to convince them we need to move it?
Does anyone else have similar problems with developers stuck in their ways?
how about the random, crashes, locking errors, freeze's, slow downs (sic).
A quick search on the web finds some useful materials:
Best Practices When Using Microsoft Office Access 2003 in a Multi-user Environment - if the changes here can't be implemented, or would effectively take a rewrite, then that is good ammunition for doing it right.
SQL Server vs MS Access - pay special attention to feature limits. Eg You can only have 32,000 objects in an access DB. Caveat: though it says 255 concurrent users, and that is probably a technical limitation, the practical limitation is really MUCH lower.
It's hard to convince people that are not willing to learn and are not open to new ideas. You can go on about speed issues, concurrency issues, security problems.. but ultimately, some people will just never listen. Go over their heads. Rewrite it in tools from this decade and show them up. Refuse to be involved with the project and further. I don't know what the political situation is, but technically, MS access is wrong for what you are doing, from what you've described.
come in on a weekend, copy the database to sql server, change the app's connect-strings to sql server, retest the application, then uninstall ms-access...everywhere.
then don't say anything about it, let him think that the problems 'fixed themselves' and that the users are still using ms-access
To me it depends on how many concurrent users you have and how big the database is. If you have more than 5 concurrent users then you should be thinking about a database server. The network traffic starts to get out of hand and with each concurrent user you add it just gets worse.
I have created reliable access based systems for years. If you are having random crashes, locking issues, and slow downs then you aren't doing something right. I typically will have an mda local with the mdb on the network when creating an app in access. To have good performance it's key to have the proper indexes and queries optimized for getting just the data you need. Whether using a separate app, access, or some app running against sql server you need to actively handle record locking properly. You can't just blindly let access lock your records.
Forget the arguments about DB Size, it is an uninformed reason to shift to a client-server platform in 90% of the cases I hear it brought up.
Your best arguments are based on features explained at a low tech level:
(1) You can backup and perform maintenance on the DB without kicking out the users (which introduces costly downtime).
(2) Faster recovery if data is accidentally deleted/mangled or corrupted. Again, less risk and less downtime. This is always a good foundation for a business case.
(3) If (and only if) you anticipate the need to scale quite a bit, the upgrade will better allow that.
(4) If you need to run automated jobs/updates, SQL can do this much more elegantly.
Remember the contra-indications for SQL, it is easy to get on your technical high-horse about this platform versus that, but you have to balance the benefits against the costs.
SQL is a Helluva lot more expensive to maintain as it requires dedicated hardware, expensive licenses (Server OS and DB) and usually at least a part time DBA that is going to cost you a bare minimum of $75K (if you get luck AND work out of Podunk Iowa).
The best possible advice I can give you is to make sure that you have a good attitude and are known as someone who does quality work and gets things done. It sounds like you don't have any control in the situation so what you need is influence.
Find a way to solve a problem (probably a different one that is less threatening to the people involved) in the way you are suggesting. Make it work blindingly fast and flawlessly. Make it work so well that people start asking for you when they need something done. Get it done quickly, which you should be able to do because you'll be using the right tools for the job.
Be a good person to work with, not the PITA that knows how everyone else should write their code. Be able to give an answer for what you might do differently and why, but don't automatically assume that your ideas are always the best. Maybe there are trade-offs that you don't know about -- no money in the budget for the extra CALs, we have this other app that needs to be done first. This doesn't sound like your situation, but looking for opportunities to understand before making constructive criticisms can go a long way to helping people be receptive.
The other thing is that this probably has nothing to do with the technical aspects of the situation and everything to do with the insecurities of the other developer. "This is all I know. If we change it, I won't understand it and then where will I be." Look for ways to help the other guy grow -- when he's having a problem, find resources that will help him develop good technical solutions. Suggest that everyone in your department get some training in new technologies. Who knows, one good SQL Server course and the guy could become the SQL Server evangelist in the organization because now THAT'S what he knows.
Lastly, know when to cut your losses, so to speak. If you find that you're not able to do anything about the situation, don't add to the complaining. Move on to something that you can control and do it as well as you can. Maybe in the future you'll be in a position that you do have control or influence in the situation and can do something about it. If you find that you're in a company that's more dysfunctional than most, find a way to move on to a place where the environment is better.
It is possible, and actually fairly easy, to convert an Access database to having the tables/views in SQL Server while still using the Access app as a front-end.
From there, your Access-obsessed developer can still have fun with all that VBA code. Meanwhile, on the back-end, you add indexes and such to speed everything up. Maybe someday you get lucky, and he asks about stored procedures. Then, the app is just a front-end, and who cares what it's written in? Your data is safe in SQL Server.
It is possible for you to do this yourself, but just leave the production app ALOOOOOOOOOOOONE. Take a copy, and convert that copy. Then, host it for a couple of users to TEST drive .. make your version of the Access app show "TEST APP" in big red letters. If your developer asks what you're doing, you can say the truth -- you are testing to see if converting only the tables/views might be of some help to the overall app.
This way, you get the best of both worlds, keep your developer happy, make the users happier (hopefully), and if you play it right, your bosses will know that you handled a knotty personnel issue with your technological prowess and your maturity.
I once had similar problems with someone I would not hesistate to call a complete idiot.
It was not possible to convince them of the issues with access. In the end it was easier to force the issue than do it "nicely", cruel to be kind.
If they resist then you can always go above their head. Management must be aware of crashes and stability related issues. Present a plan to them to improve stability and they are likely to at least listen. They will probably then want a meeting with all developers to discuss so go into it armed with plenty of ammo.
More than "How to convince them", let's talk about "How to do it without anybody noticing"!
First of all I advice you not to mix together the code optimisation issue and the SQL server one. Do not give users a chance to complain about SQL while bugs are related to something else.
If your code is really unbearable, rewrite the app before switching to SQL, keeping in mind the following points to make the final transition to SQL Server completely transparent for final users.
This is what we did 18 months ago, and I am sure we still have users thinking our database is Access:
Export current access database to SQL through available Wizard in access for testing purposes (many problems might occur, and you could need another tool such as the one proposed here).
Create a unique connection object at the application level, so that you can freely switch from Access to SQL at any time (at development level, you can even add an input box at startup to ask which connection to use). We chose an ADODB connection object, but it will also work with ODBC connection.
In case you use SQL syntax to update tables, make sure that all SELECTs, INSERTs, UPDATEs and DELETEs make use of this connection. In case you use recordset, make sure that all of them use this connection at opening time.
When needed, update all connexion specific code by adding a "SELECT CASE" type_Of_TheConnexion options
Switch to SQL connection ..and debug till you're done!
The problems you will find are mainly linked to SQL syntax, where MSSQL uses ' instead of " and # as separators. Date format is also an issue, where standard SQL format is 'YYYYMMDD' while MS-Access format depends on computer locals (beware of conversions from date to string!) and is stored as "YYYY-MM-DD" (if I remember ...). Boolean in SQL are 0 and 1, while they are True/False or 0/-1 in Access ...
Test, update code, and when you are ok, make a new data transfer, lock your app on the SQL connection, and distribute a new runtime.
It depends on the type of application and data load of your database but Access is quite efficient, even over the network.
Depending on the amount of data your users deal with you could easily scale up to a 100 users on a network just using a from and back-end Access database.
Looks like in your case a rewrite may be in order. If your application is data-centric if doesn't make much sense to develop it in VB6: the tools given by Access are much better than anything you'd be able to make, especially when considering Access 2007.
Upsizing to SQL Server is only really required if you're getting into issues of:
Security:
you need to make sure that only the rights users can access data. You can do your own security in Access, but it's never going to be as strong as SQL Server.
Scalability:
you're dealing with lots of data and complex queries or a lot of users and it would be better to have dedicated hardware to handle the load for the clients. The issue with this though is that while removing the pressure from the less-capable clients machines, you're adding a lot more to the server.
Integrity:
With the back-end database being just a file that needs R/W access for all connected clients, there's always the possibility that someone is going to do something bad or that a client may crash and leave the database corrupted.
If your number of users is average (I'd say 30), then there's probably no real need to upscale:
Use MS Access 2007 to develop your application, then just use the MS Access 2007 Runtime (it's free!) on all client machines to get a more modern user interface (uses the Ribbon and has lots of UI enhancements over previous versions).
You can't be the cheapness of that solution : you only need full retail version of MS Access and all the rest is free, regardess of the number of users!
Don't think that moving to SQL Server is going to improve performance of your queries: MS Access often does a better job of optimizing the queries for you (it knows what needs to be displayed and does lots of caching and optimization).
Make sure you only edit small amounts of data at any one time (don't use dynaset queries just to display vast amounts of data in a datasheet; use a snapshot instead and open a detail form that only contains the data to edit when necessary.
Cache complex queries locally.
Built some caching mechanism that leaves a copy of the results of a complex query on the local machine. The gain in performance is pretty amazing and if the query doens't change much (for instance a log of stock operations) you can just persist the complex/big query locally and append new records as necessary.
There is so much more to say.
Bottom line is: you may be looking at a rewrite, but don't dismiss Access as the solution because your current application was poorly written.
Try bechmarking and showing the stats to him
Making people change can sometimes be a real pain in the butt.
I would have to say the main argument would have stability and speed, but of course like you have said they already know this a still won't move.
Another thing to try would be to show them the power of LINQ to SQL and how much cleaner it would make your application. Like Daniel Silveira said you could try and throw a couple of stats there way and see if they are convinced.
We have a app build using MS access as a back end and I can't wait till we get our new SQL server so I can move everything to that.
You could show him the perf results comparing the two, but if he's really set in his ways and refuses to change, there isn't much you can do except force him somehow.
If you're his boss then just force him to change it to use SQL. If not, then convince your boss to force the change by showing him the perf results and explain it'll fix the issues you're having.
Errr, leave the team? You seem to be working with the totally wrong set of people. Now, if the team IS your company, then you are working with the wrong company.
Of course once you leave the company, you could tell your clients that you could solve the network problems on their own and make them leave the company as well. Then give them an improved system that works on SQL Server Express.