Querying multiple MS SQL database instances on the same machine - sql-server

I am new to MS SQL and I am trying to do something that seems simple but is driving me crazy.
I want to write a query to pull data from two databases. Each database is on a different instance on the same DEV machine. (one is MS SQL 2008 and the other MS SQL 2005). I am using the Microsoft SQL Server Management Studio (MSSMS).
I have the basics figured out. I know the format of the query and what I need to do. My big problem is figuring out what the NAME of each server is?
SELECT LastName
FROM [servername1].CHA2.dbo.Customer
UNION
SELECT LastName
FROM [servername2].OBXKites.dbo.Contact
ORDER BY LastName
I used the server name that I connect to MSSMS (DLPT\HENRY) with and what is also returned by ##SERVERNAME
SELECT ##SERVERNAME returns DLPT\HENRY
I tried
DLPT\HENRY.CHA2.dbo.Customer
did not work
I tried it without the DLPT HENRY.CHA2.dbo.Customer
did not work
I need to future out what the NAME of the server is to use in the query.

[DLPT\HENRY].CHA2.dbo.Customer
The namo contains a backslash which is normally illegal in an identifier. You surround illegal names with brackets.
Note that you surround just the server name. In other words, it is [DLPT\HENRY].CHA2.dbo.Customer, not [DLPT\HENRY.CHA2.dbo.Customer].

You have to configure Linked servers. Then only different instances of SQL Server are able to communicate with each other.

Unfortunately you can't access tables in databases in separate SQL Server instances by default. You have a couple of options here - neither are simple and might require help from a DBA:
1) Use linked servers like this:
http://technet.microsoft.com/en-us/library/ff772782(v=sql.110).aspx
Then you will be able to refer to the second table in the format INSTANCENAME.DatabaseName.SchemaName.TableName
2) Use replication to get the table from the second database into the first database. Then the contents of the second table will be synched to the first database in more or less real time
Read about SQL Replication here

Related

Oracle ODBC connection to SQL Server: Table Name Length Issues

I'm running into a problem when accessing a SQL Server table from an Oracle setup via ODBC.
I can access 90% of the tables absolutely fine, but there's a few tables that have a name that's longer than 30 characters. Whenever I try to interact with the table (describes, selects, etc) Oracle throws an "identifier too long" error and gives up.
Is there a way to coax Oracle into playing nice with the SQL Server tables?
Assuming that we are talking about an Oracle database that has a database link created to a SQL Server database via Heterogeneous Services, you would need to write code using the DBMS_HS_PASSTHROUGH package to interact with the tables in question. You'd also need to use this package if you have tables where there are column names that are not valid Oracle identifiers.

Can't find table object name

I have an application in classic ASP, and a database in SQL server 2005.
I transfer the database in SQL server express edition and I have one strange problem, I can see the tables in the database in this way:
information_Schema.dbo.test, so when I execute SQL command
select * From test
I get error that it can't find the table.
When I execute
select * From information_Schema.dbo.test
I do get results.
The problem is that my application is many many files and I can't rewrite the SQL commands.
Is there any way to find a solution in SQL without changing anything in my application?
I would guess you are not connecting to the information_Schema database but to some other db that does not contain the table. Did you put the table in the wrong place(Information_Schema doesn't sound like a typical application db location to me) or is your connection wrong?

MS Access 2007 queries does't run on SQL Server 2008

I am developing an application in C# VS 2010 past 4 months. I used MS Access 2007 to store my nearly 20 tables successfully.
Today I realized that my data base cannot be handled consistently by MS Access 2007. Hence I decided to go for SQL Server 2008 R2 Express with Upsizing wizard and it worked really great!
However, when I tried to run various options of my already well developed application, It kept throwing error each time when a query is fired to SQL Server.
I understood that Many of the stuffs of SQL supported by MS Access are not supported by MS SQL Server
For example: query with date, for representing date format when we use '#', SQL Server 2008 won' t recognize it.
Also, for Bool value, MS Access stores it as True and False where as SQL Server uses 0.
These all queries worked perfect with Access 07
I am sure that there must be some method so that SQL Server can understand MS access queries.
Or will I have to edit my whole application?? It will be as good as digging a mine for earning gold..
I have changed all data access objects such as reader, adapter, command, connection to SQL data objects using System.Data.SqlClient.
So, It is not the problem.
Please help me asap.
Thank you.
You cannot force SQL Server to run the MS Access queries. These queries will need to be rewritten to use T-SQL instead of the query language that MS Access uses.
I feel your pain, I just had to rewrite a large MS Access application (over 1k queries) that needed to be recreated to be used in SQL Server.
There will be some queries that might be able to be ported over directly but as you noticed queries with date, and even some of the aggregate functions (First(), etc) are not used in SQL Server and those queries will need to be changed.
Here is a link with some info on converting Access to SQL
Converting Access Queries to SQL Server
You are right that, most of the time, you cannot just take the SQL of a query from Access and run it within SQL Server. It may work for very simple queries, but usually you need to tweak them.
There are a few steps I would take:
Extract your queries (which I presume are in your code), and re-create them in your Access database. Make sure they work there as normal Access queries.
(you can for instance simply add some code to your app to print all queries to files so you don't have to mess with parameters, then just copy/paste them in your Access DB).
The point is simply to have working queries within Access.
Use SSMA from Microsoft for helping you to move your queries to SQL Server. It does a good job of translating them into T-SQL.
You may still have to convert some troublesome queries by hand, but it shouldn't be that many and usually the conversion is not difficult.
Once converted to T-SQL, just re-inject these working queries into your code, or keep the complex queries in SQL Server as views (which it usually be faster as SQL Server will have already created its execution plan, rather than your application sending raw SQL that the server needs to analyse).
As you pointed out, there could be some issues if your fields use some features that don't cross-over to SQL Server properly.
Look at your tables in Access and do some cleanup before attempting to convert:
For booleans fields:
Make sure you set their default values to 0 or 1 (they should not be empty).
Required fields must be non-null:
Make sure that any fields that you have set as 'Required' does not contain any NULL values in its data.
Unique indexes cannot ignore Null:
Check that your indexes are not set to be both 'Unique' and 'Ignore null'.
All tables must have clean primary keys:
Make sure all your tables have a unique primary key that doesn't have Null values in their data.

Move data from SQL Server to MS Access mdb

I need to transfer certain information out of our SQL Server database into an MS Access database. I've already got the access table structure setup. I'm looking for a pure sql solution; something I could run straight from ssms and not have to code anything in c# or vb.
I know this is possible if I were to setup an odbc datasource first. I'm wondering if this is possible to do without the odbc datasource?
If you want a 'pure' SQL solution, my proposal would be to connect from your SQL server to your Access database making use of OPENDATASOURCE.
You can then write your INSERT instructions using T-SQL. It will look like:
INSERT INTO OPENDATASOURCE('Microsoft.Jet.OLEDB.4.0','Data Source=myDatabaseName.mdb')...[myTableName] (insert instructions here)
The complexity of your INSERTs will depend on the differences between SQL and ACCESS databases. If tables and fields have the same names, it will be very easy. If models are different, you might have to build specific queries in order to 'shape' your data, before being able to insert it into your MS-Access tables and fields. But even if it gets complex, it can be treated through 'pure SQL'.
Consider setting up your Access db as a linked server in SQL Server. I found instructions and posted them in an answer to another SO question. I haven't tried them myself, so don't know what challenges you may encounter.
But if you can link the Access db, I think you may then be able to execute an insert statement from within SQL Server to add your selected SQL Server data to the Access table.
Here's a nice solution for ur question
http://www.codeproject.com/Articles/13128/Exporting-Data-from-SQL-to-Access-in-Mdb-File

Function like USE to point to a SQL database on a different server?

In SQL Server, you can apply the use function to point a query to another database. For example:
USE databasename
GO;
Is there a function that allows you to point to a different database server and use a database on that server? I would expect this to work, but no luck:
USE [servername].databasename
GO;
I know I could just point the query to the database on the other server, but when I am dealing with production versus staging environments, it's more efficient to declare the server and database in the beginning of the query.
Thanks
USE does not span across to another server, you need to define a linked server on your local instance and then you can access data from that server.
I use Linked Servers to accomplish this. I don't know if this will meet your needs, however.
http://msdn.microsoft.com/en-us/library/ms188279.aspx
In Management Studio, this is available under Database/Server Objects/Linked Servers.
You can refer to objects on this server like this:
[Server].database.schema.object
I just realized this isn't what you want. JonH has it right, you can't specify a dabase on another server at the beginning of your query.

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