I m using Access 97 database.It has lots of forms. Data bulked. I have to upgrade it quickly. I bought SQL Server 2005 enterprise edition.
I want to use SQL Server for data holder. I m going to use Access forms regularly. I just want to export data to the sql server.
Is it possible to use "Linked" data storing?
While I agree with HLGEMs first paragraph I respectfully disagree with HLGEMs second paragraph. There are quirks you need to know about of which I'm somewhat ignorant. Such as changing boolean fields to LittleInt. But otherwise it's a lot of tedious work to recreate the database schema. And it'll be error prone such as missing indexes or relationships.
There is a tool from the SQL Server group which is a lot better than the Upsizing Wizard especially the Access 97 version.
SQL Server Migration Assistant for Access (SSMA Access)
http://www.microsoft.com/sql/solutions/migration/access/default.mspx
As you discover these quirks you can change the scripts to recreate the database with the appropriate changes.
I concur with Tony Toews (and you should trust him on this, he's an Access guru): use SSMA to help you move data to SQL Server, it does a more complete job than the upsizing Wizard integrated in Access (which doesn't work for upsizing to SQL Server 2008 anyway).
You have to be wary of a few caveat though; I've made a blog post about some of the things you should check out.
The point is that if the original Access database was designed without relying too much on the liberties that Access allows (strange characters in table and column names for instance), then the process will be much easier.
Pay special attention to all the warning and errors reported by SSMA, they are really useful in helping you focus on the issues you must solve.
With regards to performance, moving to SQL Server isn't necessarily going to make things faster.
In some areas it will actually be slower, sometimes much much slower:
Access is pretty good at optimizing certain forms of data access but once the database moves outside of its reach, it doesn't have as much control.
Most things will work fine though.
You will probably have to rewrite a few queries, maybe move them as views on SQL Server instead of keeping them in your Access application.
Little things such as using % instead of * as wildchars in queries using LIKE in their WHERE clause can also cause strange issues like queries not returning any records.
By the way, I'll post a very good resource Tony has on his own website regarding SQL upsizing: My random thoughts on SQL Server Upsizing from Microsoft Access.
There is also a good and detailed read about things to consider when using SQL Server from Access: Optimizing Microsoft Office Access Applications Linked to SQL Server
YOu can add the SQL Server tables to access as linked tables. Then you will want to start looking at your slowest queries and convert them to stored procs.
Do not use the upgrade wizard in Access to create the SQl Server tables becasue it will make poor choices for datatypes. Do the work yourself to create the scripts, choosing the best datatypes. It takes longer this way, but your database will perform better and you will gain a better understanding of how to do things in SQL Server. You should start right now, learning to do everything through a script and never from the GUI. Best to learn good habits in SQL Server from the start.
Related
Is there seriously no way of using a shared access non-server driven database file format without having to use an SQL Server? The Entity Framework is great, and it's not until I've completely finished designing my database model, getting SQL Server Compact Edition 4.0 to work with Visual Studio that I find out that it basically cannot be run off a network drive and be used by multiple users. I appreciate I should have done some research!
The only other way as far as I can tell is to have to set up an SQL server, something which I doubt I would be able to do. I'm searching for possible ways to use it with Access databases (which can be shared on a network drive) but this seems either difficult or impossible.
Would I have to go back to typed DataSets or even manually coding the SQL code?
Another alternative is to try using SQL
Install SQL Server express. Access is not supported by EF at all and my experience with file based databases (Access, SQL Server CE) is mostly:
If you need some very small mostly readonly data to persist in database you can use them (good for code tables but in the same time such data can be simply stored in XML).
If you expect some concurrent traffic and often writing into DB + larger data sets their performance and usability drops quickly. They are mostly useful for local storage for single user.
I'm not sure how this relates for example to SQLite. To generate database from model for SQLite you need special T4 template (using correct SQL syntax).
Have you tried SQLite? It has a SQL provider, and as far as I know EF supports any provider. Since it's file-based, that might be a plausible solution. It's also free.
I don't know between ADO, DAO and DLookUps and such. Does anyone know?
I find that the application bottleneck is usually the actual SELECT/INSERT/UPDATE on the DB and not how the application calls it. if you are worrying about speed make sure you have well designed tables and indexes.
Regarding DAO vs ADO, I'm not sure about a difference in performance but there is a difference in available functionality.
There is a microsoft article showing the differences in a nice table. Choosing ADO or DAO.
It also states:
"In particular, ADO is a good choice if you are developing an Access database solution that will later be upgraded to SQL Server — you can write your ADO code to minimize the number of changes that will be required to work against a SQL Server database. In addition, ADO is a good choice for developing new data access components that work with SQL Server, multidimensional data, and Web applications."
Seems like ADO might be the way to go.
I don't know anything about DLookUps though.
Hello,
I'm new here, so sorry, if my question is too basic. However, maybe you have some advice, example, links, which could help me... I'm trying to find something helpfull for few days, but no results as for now.
I'm working in a distributed environment. I have a Oracle server hundreds of miles away and a MS SQL server close to me. I'm writing a application using Visual Web Developer 2008 Express. I need some data from Oracle. It's not worth to query the Oracle server every time i need some data from it. I'd prefer to run some Oracle queries once each night and store results in some local (SQL Server) tables. I assume, I should run queries through standard windows scheduler (Windows Server 2008). I have the basic connectivity - I can open Oracle Database from local Visual Studio.
The questions are:
How to write a query/procedure/function that would get data from Oracle and put them into a SQL Server table (possibly recreated before each query run)?
How can I run such a query from command line (or in other way run from scheduler)
What naming conventions are applicable? In VS I use something like //IP.IP.IP.IP/Name and a user with password.
Thanks for any help or advice.
Regards,
Matteo
I suggest you speak to the DBA's of the Oracle and SQL Server databases, as there may be other considerations you need to bear in mind. (Data Integrity, Security, ownership etc.)
One route you could follow would be to implement DTS (For older databases) or SSIS (for new versions of SQL Server) processes to copy the data across on the schedule you want. (This is pretty much what they were built for.)
How much data are we talking about?
If there is a small quantity that you need to transfer every day, you can write a stupid fetch and insert script in language of your choice.
You only need to search for better solutions if "sync" would take too much resources.
Thanks...
I'm the DBA for the SQL Server, which will serve only for my application. For Oracle I just want to read data and I have enough privileges and agreement with DBA's. Security, ownership and integrity are not an issue for now. I just need some technical advise how to get data from Oracle to MSSQL tables on a schedule.
I use MS SQL Server 2008 Express SP1. I'm very close to solve my problem - I have established connections and everything installed and working. I just don't know, how to run a query, which would get data from Oracle and put into MSSQL, on regular basis, without manual interaction.
I've some experience in programming, but not much in databases (except creating complex SQl queries). Therefore some example or links to detailed description would be helpful. I'm not sure about naming conventions, differences between procedures, functions and queries, command line options to run db automation procedures and so on. I'm also not sure, about which mechanisms or technologies are available in MS SQL Server 2008 Express edition.
Bear in mind here, I am not an Access guru. I am proficient with SQL Server and .Net framework. Here is my situation:
A very large MS Access 2007 application was built for my company by a contractor.
The application has been split into two tiers BY ACCESS; there is a front end portion that holds all of the Ms Access forms, and then on the back end part, which are access tables, queries, etc., that is stored on a computer on the network.
Well, of course, there is a need to convert the data storage portion to SQL Server 2005 while keeping all of these GUI forms which were built in Ms Access. This is where I come in.
I have read a little, and have found that you can link the forms or maybe even the access tables to SQL Server tables, but I am still very unsure on what exactly can be done and how to do it.
Has anyone done this? Please comment on any capabilities, limitations, considerations about such an undertaking. Thanks!
Do not use the upsizing wizard from Access:
First, it won't work with SQL Server 2008.
Second, there is a much better tool for the job:
SSMA, the SQL Server Migration Assistant for Access which is provided for free by Microsoft.
It will do a lot for you:
move your data from Access to SQL Server
automatically link the tables back into Access
give you lots of information about potential issues due to differences in the two databases
keeps track of the changes so you can keep the two synchronised over time until your migration is complete.
I wrote a blog entry about it recently.
You have a couple of options, the upsizing wizard does a decent(ish) job of moving structure and data from access to Sql. You can then setup linked tables so your application 'should' work pretty much as it does now. Unfortunately the Sql dialect used by Access is different from Sql Server, so if there are any 'raw sql' statements in the code they may need to be changed.
As you've linked to tables though all the other features of Access, the QBE, forms and so on should work as expected. That's the simplest and probably best approach.
Another way of approaching the issue would be to migrate the data as above, and then rather than using linked tables, make use of ADO from within access. That approach is kind of famaliar if you're used to other languages/dev environments, but it's the wrong approach. Access comes with loads of built in stuff that makes working with data really easy, if you go back to use ADO/Sql you then lose many of those benefits.
I suggest start on a small part of the application - non essential data, and migrate a few tables and see how it goes. Of course you back everything up first.
Good luck
Others have suggested upsizing the Jet back end to SQL Server and linking via ODBC. In an ideal world, the app will work beautifully without needing to change anything.
In the real world, you'll find that some of your front-end objects that were engineered to be efficient and fast with a Jet back end don't actually work very well with a server database. Sometimes Jet guesses wrong and sends something really inefficient to the server. This is particular the case with mass updates of records -- in order not to hog server resources (a good thing), Jet will send a single UPDATE statement for each record (which is a bad thing for your app, since it's much, much slower than a single UPDATE statement).
What you have to do is evaluate everything in your app after you've upsized it and where there are performance problems, move some of the logic to the server. This means you may create a few server-side views, or you may use passthrough queries (to hand off the whole SQL statement to SQL Server and not letting Jet worry about it), or you may need to create stored procedures on the server (especially for update operations).
But in general, it's actually quite safe to assume that most of it will work fine without change. It likely won't be as fast as the old Access/Jet app, but that's where you can use SQL Profiler to figure out what the holdup is and re-architect things to be more efficient with the SQL Server back end.
If the Access app was already efficiently designed (e.g., forms are never bound to full tables, but instead to recordsources with restrictive WHERE clauses returning only 1 or a few records), then it will likely work pretty well. On the other hand, if it uses a lot of the bad practices seen in the Access sample databases and templates, you could run into huge problems.
It's my opinion that every Access/Jet app should be designed from the beginning with the idea that someday it will be upsized to use a server back end. This means that the Access/Jet app will actually be quite efficient and speedy, but also that when you do upsize, it will cause a minimum of pain.
This is your lowest-cost option. You're going to want to set up an ODBC connection for your Access clients pointing to your SQL Server. You can then use the (I think) "Import" option to "link" a table to the SQL Server via the ODBC source. Migrate your data from the Access tables to SQL Server, and you have your data on SQL Server in a form you can manage and back up. Important, queries can then be written on SQL Server as views and presented to the Access db as linked tables as well.
Linked Access tables work fine but I've only used them with ODBC and other databases (Firebird, MySQL, Sqlite3). Information on primary or foreign keys wasn't passing through. There were also problems with datatype interpretation: a date in MySQL is not the same thing as in Access VBA. I guess these problems aren't nearly as bad when using SQL Server.
Important Point: If you link the tables in Access to SQL Server, then EVERY table must have a Primary Key defined (Contractor? Access? Experience says that probably some tables don't have PKs). If a PK is not defined, then the Access forms will not be able to update and insert rows, rendering the tables effectively read-only.
Take a look at this Access to SQL Server migration tool. It might be one of the few, if not the ONLY, true peer-to-peer or server-to-server migration tools running as a pure Web Application. It uses mostly ASP 3.0, XML, the File System Object, the Data Dictionary Object, ADO, ADO Extensions (ADOX), the Dictionary Scripting Objects and a few other neat Microsoft techniques and technologies. If you have the Source Access Table on one server and the destination SQL Server on another server or even the same server and you want to run this as a Web Internet solution this is the product for you. This example discusses the VPASP Shopping Cart, but it will work for ANY version of Access and for ANY version of SQL Server from SQL 2000 to SQL 2008.
I am finishing up development for a generic Database Upgrade Conversion process involving the automated conversion of Access Table, View and Index Structures in a VPASP Shopping or any other Access System to their SQL Server 2005/2008 equivalents. It runs right from your server without the need for any outside assistance from external staff or consultants.
After creating a clone of your Access tables, indexes and views in SQL Server this data migration routine will selectively migrate all the data from your Access tables into your new SQL Server 2005/2008 tables without having to give out either your actual Access Database or the Table Contents or your passwords to anyone.
Here is the Reverse Engineering part of the process running against a system with almost 200 tables and almost 300 indexes and Views which is being done as a system acceptance test. Still a work in progress, but the core pieces are in place.
http://www.21stcenturyecommerce.com/SQLDDL/ViewDBTables.asp
I do the automated reverse engineering of the Access Table DDLs (Data Definition Language) and convert them into SQL equivalent DDL Statements, because table structures and even extra tables might be slightly different for every VPASP customer and for every version of VP-ASP out there.
I am finishing the actual data conversion routine which would migrate the data from Access to SQL Server after these new SQL Tables have been created including any views or indexes. It is written entirely in ASP, with VB Scripting, the File System Object (FSO), the Dictionary Object, XML, DHTML, JavaScript right now and runs pretty quickly as you will see against a SQL Server 2008 Database just for the sake of an example.
It takes perhaps 15-20 seconds to reverse engineer almost 500 different database objects. There might be a total of over 2,000 columns involved in this example for the 170 tables and 270 indexes involved.
I have even come up with a way for you to run both VPASP systems in parallel using 2 different database connection files on the same server just to be sure that orders entered on the Access System and the SQL Server system produce the same results before actual cutover to production.
John (a/k/a The SQL Dude)
sales#designersyles.biz
(This is a VP-ASP Demo Site)
Here is a technique I've heard one developer speak on. This is if you really want something like a Client-Server application.
Create .mdb/.mde frontend files distributed to each user (You'll see why).
For every table they need to perform an CRUD, have a local copy in the file in #1.
The forms stay linked to the local tables.
Write VBA code to handle the CRUD from the local tables to the SQL Server database.
Reports can be based off of temp tables created from the SQL Server (Won't be able to create temp tables in mde file I don't think).
Once you decide how you want to do this with a single form, it is not too difficult to apply the same technique to the rest. The nice thing about working with the form on a local table is you can keep a lot of the existing functionality as the existing application (Which is why they used and continue to use Access I hope). You just need to address getting data back and forth to the SQL Server.
You can continue to have linked tables, and then gradually phase them out with this technique as time and performance needs dictate.
Since each user has their own local file, they can work on their local copy of the data. Only the minimum required to do their task should ever be copied locally. Example: if they are updating a single record, the table would only have that record. When a user adds a new record, you would notice that the ID field for the record is Null, so an insert statement is needed.
I guess the local table acts like a dataset in .NET? I'm sure in some way this is an imperfect analogy.
We don't need multiuser. Just relational. Our app currently uses Access but Access isn't exactly zero-administration because it's prone to corruption.
Is SQLite rock, rock solid, pure zero-administration?
Or...is there a way to configure SQL Server as a desktop engine so that it is pure zero admin?
Or...is there some other relational choice?
We are using ADO as the layer to talk to Access, so switching to SQL Server wouldn't be hard, but my understanding is that I couldn't use ADO for SQLite, so switching to SQLite would require a lot of rewriting. Is that right?
Other databases may be more stable than Access, but I'm not aware of anything that's as easy to use, and as easy for an end user to understand. Access (like SourceSafe) is always called "prone to corruption", but few and far between are the first-hand accounts of this. Most people "read it somewhere."
Consider just including a backup routine with your app that keeps the last two or three copies of the Access database if you're that worried about corruption.
If you insist on something else, then try SQL Server Compact Edition (as other have suggested), which (like Access) is just a file, a .sdf file in this case, and a few DLLs. Unlike SQL Server Express Edition, SQL Server CE doesn't leave a background process running all the time.
Another option is embedded Firebird.
The most easy switch would be to go with SQL Server compact edition, it can be embedded in your app, and from some light testing that I have done, it works really well.
Going to SQL lite will require more modification of the DAL.
NOW note that SQL Compact Edition doesn't support stored procedures! (Shouldn't be a big deal, but be sure to research the differences)
There are ADO.NET wrappers for SQLite, not sure if that is what you want or just straight ADO. I have found SQLite to be very robust although you do need to VACUUM the database every now and then to recover unused space after deletions. You can do that from your code, so that isn't really administration. I just do it at startup or shutdown.
I agree with the others' opinions about SQL Express Edition. I use it for several apps.
If you are working with .NET, then you might want to look at Subsonic for your data access. It supports all of the above and more and makes switching fairly painless. For single user database apps, it is great. If you are going to do a rewrite, then it is worth it.
Since you are looking at no need for multiuser, you might want to check out SQL Server Compact Edition. http://www.microsoft.com/Sqlserver/2005/en/us/compact.aspx