I have a question. In SQL server, we can access a table or view in a different database by using the dot notation in the table name, so I believe that in SQL server, if we say just 'tablename' it will refer to the table name in the current active DB, but if we say 'DBname'.'Tablename' you can access the table in a different DB on the same server, and if you say 'serverName'.'DBName'.'tableName' we can access a table in a remote DB whose DBName is defined in a connection setting. I believe we can define a connection setting between two SQL server to access a different database. So, instead of copying the data from one DB to other and duplicate the same, it might be better to simply define a view.
Can anyone please help me if we can do so and how?
Using Linked Server you can access two different servers.
use the below link to add the linked server.
http://sqlserverplanet.com/dba/how-to-add-a-linked-server
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I have a SQL database and I want to link an Access table in the SQL database. Most of the online articles and videos show how to link the two databases from Access but not from SQL. I want the access table linked in SQL database so that every time the table gets updated in Access, the table in SQL server gets updated as well. Thanks!
You can do that. It's called a Linked Server and will link your Access database in SQL Server where you typically will create a view to read the Access tables to avoid the DatabaseName..TableName syntax otherwise needed.
However, it will probably not work for you because SQL Server will insist on opening the linked Access database exclusively, meaning that you cannot open it later from your Access application. And if you open it first in Access, an attempted reading from SQL Server will fail because SQL Server cannot get exclusive access.
You may argue, that a shared access should be possible, and connection parameters indicate this, but I haven't found a way to achieve this.
So, as others have mentioned, you may have turn this upside/down, and use, say, ODBC to link the SQL Server tables in your Access application, and then let this take care of the maintenance of the SQL Server tables.
It must be like this (SQL SERVER) => (MS Access)
and yes you are correct, it's called linked tabled in Ms Access. In order to link a table from another database, you must have
Correct drivers installed. (ODBC)
Know the login details of your SQL server and have sufficient permission in SQL server
Go to MS Access -> External data -> ODBC Databse -> link to the data source by creating a linked table ->
Now you can select a DSN file where your sql server credentials are saved, or you can make "new" and follow the steps to get connected to the SQL server.
Once connected, you will be presented with a list of all the tables from SQL server. Select the table you want to link and finish the wizard.
You now have SQL table connected in MS Access and can input data directly.
We have an Access db that acts as a company-wide backend--containing a master list of contacts, clients, etc. Almost every other database relies on this one via linked tables. However, we would like to migrate this backend to SQL Server with as few interruptions/breakages as possible. Our thought was to replace the tables in the Access backend with linked ODBC tables (keeping the same name), however when trying this we found that other Access files could no longer see the tables. Is there a way to do this or will we have to change all linked tables throughout our company to point to the new SQL backend?
will we have to change all linked tables throughout our company to
point to the new SQL backend?
Yes. You can create a link to a TableDef which is a native table in another Access database --- that is what you have now. But Access will not allow you to create a link to a TableDef in another Access database when that TableDef is actually a link to an object in yet another database. In other words, you can't link to a link.
So you must change all the links which point to the migrated Access tables so that they will now point directly to the SQL Server tables.
I have an access 2003 database that holds all of my business data. This access database gets updated every few hours during the day.
We're currently writing a website that will need to use the data from the access database. This website (for the time being) will have only read only capabilities. Meaning there will only need to be one way transfer of data (Access -> SQL).
I'm imaging there's a way to perform this data migration from access to SQL server programatically. Does anyone have any links to something I can read about?
If this practice sounds odd, and you'd like to suggest another way to do this (or a situation where data can go both ways (Access -> SQL, SQL -> Access), that's perfectly fine.
The company is going to continue using Access 2003 for their business functionality. There's no way around that. But I'd like to build the (readonly) website on top of SQL Server.
The strategy you outlined can be very challenging. You could use INSERT queries to copy new Access rows to SQL Server, as described in another answer.
However, if you have changes to existing Access rows, and you also want those changes propagated to SQL Server, it won't be so simple. And it will be more complicated still if you want deleted Access rows deleted from SQL Server, too.
It seems more reasonable to me to use a different approach. Migrate the data to SQL Server once. Then replace the tables in your Access database with ODBC links to the SQL Server tables. Thereafter, changes to the data from within your Access application will not require a separate synchronization step ... they will already be in SQL Server. And you won't need to write any code to synchronize them.
If your concern is that the connections between the web server and SQL Server be read-only, just set them up that way. You can still independently allow read-write permissions for your Access application.
To do the initial data migration and set the SQL Server automatically, I would use the SQL Server Migration Assistant. The only thing you should definitely change that I can think of would be to turn off the Identity property on any columns that have it - to be explained below (MS Access calls Identity autonumber). Once you have your tables loaded, you can set up a dsnless connection to the database (and tables) you just created.
I haven't used the method just linked, but I believe it allows you to use SQL Server authentication to connect to the db. The benefit of using this method is you can easily change which SQL Server instance and/or database your are connecting to for development and testing.
There might be a better, automated way, but you can create several insert queries doing left joins from the primary key of the Access table to the SQL Server table, and putting a WHERE clause that specifies the SQL Server PrimaryKey must be null. This is why you need to turn off the Identity property in the SQL Server tables, so that you can insert the new data.
Finally, put the name of each query in one function, then run the function periodically.
I have used Microsoft's free SQL Server Migration Assistant (SSMA) to migrate Access to SQL Server. The tool is very simple to use. The only problem I have encountered with the tool was overloaded data types when migrating. What I mean by this is a small string will get converted to a NVARCHAR(MAX) in some instances. Otherwise, the tool is very handy and can be reused after setting up a 'profile'.
I am attempting to keep a table in Sql server updated from an access table. Any time a change is made in the access table I would like that change reflected in the sql server table. The two tables can be identical. I have created an ODBC connection from access to sql server and can export the table to sql server; I just don’t know what must be done to keep that table updated. Any suggestions are appreciated.
Should this be implemented from within Access or within sql server?
Can you just add the SQL Server table to the Access database as a linked table? (Useful article on how to add linked tables)? That way users (let's hope there's not many!) of the Access database are in effect editing the SQL Server table directly.
If this isn't desirable then how about creating another table in the SQL Server database, and adding this to the Access database as a linked table. Then, add a trigger so that when an insert/update/delete is made to this table the same operation is done on your main table.
I think setting up a Linked Server in SQL Server could be easier to implement than an automatic export of data from Access.
According to the MSDN page,
Many types OLE DB data sources can be configured as linked servers, including Microsoft Access and Excel.
Server-on-SQL-2005-Server/
Access has no "event" that occurs when a row is updated/inserted/deleted that I know of. as JeffO points out data macros that could do what you want.
You could also periodically synch them. There are several techniques to periodically do the synch task (SQL Server Agent, Windows Service, Windows Scheduler, a timer in an application etc.), but still have to deal with all the problems that exist with synchronization if both tables can be modified, the worst being data conflict resolution. There is no easy solution for that.
Perhaps if you explained the problem you have that you are solving with synching data in SQL server and Access someone might be able to point you in the direction of a solution that doesn't have these problems.
I have two databases, one MSSQL and the other in Access.
Right now, inside the access file, the mssql tables are set up as linked tables so queries can be written using tables from both databases. (e.g. "select * db1.table1 where db1.table1.somevalue not in db2.table1", or select into tables like that one)
These queries need to be moved into a VB.NET project, but still be linked to the access file.
I think what I am needing is a Database object that can have tables from 2 different connections, (ie the SqlClient and OleDb connections)
Is this possible? If so, how? Or do I need to rewrite the queries using loops or something?
What I would do is query your access database to get some result set and that pass that result set as a parameter to a stored procedure in your MS SQL database. You would just have to transform your results from access into XML to be passed as a xml variable as a parameter. And then in your stored procedure you can convert the XML to be a table variable and you can use it just like a regular table.
THere is no reason you can't create an MS Access .mdb with Links to your MS Access Database and your SQL Server database
Access Db #1 Contains Access Tables and Data.
SQL Db Contains your MS SQL Tables.
Access Db #2 contains links to the tables in Access DB #1 as well as links to the tables in your SQL Server Db. This .mdb files ALSO contains your query defs required by your vb.net project.
I'm pretty sure you can just connect to the Access database. All the internal objects--including the links to SQL Server tables--should be accessible to your vb.net project.