Does SQLAlchemy support Query Notifications of SQL Server?
If not, what is the closest one could get?
I can imagine I could probably get SQLAlchemy directly submit Trasact SQL queries to set up the query notifications, but is there any more generic way?
In the end what I want is to be informed of any changes to the database that affects my query. This is for a FLASK web server that should then in turn push the updates to the clients showing some calculated information.
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I work on multiple Azure databases, using AzureAD - Universal with MFA in SSMS.
I usually have a number of different scripts on the go, comparing results between the different databases, then an hr or so later, the connection is terminated by the server and if I try to re-run it, it tells me doesn't recognise the table, because it no longer knows which database to connect to.
Is there a way to specify the database within SSMS, if I try USE dbDocument before the script, it tells me Msg 40508, Level 16, State 1, Line 1 USE statement is not supported to switch between databases. Use a new connection to connect to a different database..
Is there any way around this, without having to right-click the db in question and hitting NEW QUERY?
The USE statement is not supported on Azure SQL Database. One solution is to split your work to several different steps according to the database that you want to use, and connect to the right database for each step.
If you want to execute the same query on multiple Azure Databases then you can use one of these options:
Use horizontal partitioned databases based on shard map using the elastic database. Here you can find how to query a remote database.
You can also use elastic queries.
Or you can create your solution based on Azure Data Lake.
Looking at this MS doc, I doubt this is possible at all...
If a database other than the current database is provided, the USE statement does not switch between databases, and error code 40508 is returned. To change databases, you must directly connect to the database. The USE statement is marked as not applicable to SQL Database at the top of this page, because even though you can have the USE statement in a batch, it doesn't do anything.
I'm dealing with a three piece datapath: client application, host integration server, db server. Client application (MS Mashup Engine) is generating queries that pass through MS SQL Server to a legacy IBM iSeries DB backend.
I'm running into issues where the client is generating queries like
select * from x where numericValue = 1.46510+003
I'm checking the execution plan for these on the SQL Server and they result in a full data load with the comparison occurring on SQL Server (which is acting as the Host Integration Server).
By comparison, a human generated query
select * from x where numericValue = 1465.1
results in no scan and performance two orders of magnitude faster.
I have tried playing with the client application to force it to generate something like the human generated query, but I've had no luck.
I'm not sure if I can massage the way the query plan is generated in SQL server by playing with column data types. I.e. exposing a view over the backend DB with explicitly defined data types. Or otherwise forcing query plan generation?
Any thoughts?
I'm not sure if I can massage the way the query plan is generated in SQL server by playing with column data types. I.e. exposing a view over the backend DB with explicitly defined data types. Or otherwise forcing query plan generation?
No, the answer is no using all of the following:
casting types prior to delivering to power query/power bi changes nothing
adapter properties set for DB2OLEDB or IBMDASQL ( f.ex. Decimal As Numeric=True; Derive Parameters=True; etc...) have no effect
creating stored procedures over the data requires parametrization in power query which is fine, but does not integrate with the ui. I.e. - using a parameter field instead of the column filters is not clean.
TBH, this has become less and less of a problem as backend performance improves and frontend caching is available.
Hope it helps,
-Alex T.
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'.
my client has SQL Server with some customer info and I am developing e-shop using MySQL database. What we need is to keep the database of customer loyalty points synchronized. When customer buys a product in an ordinary shop (not e-shop) these are recorded on SQL Server (via some accounting app). The problem is that I need this information to get to the MySQL server which stores information for the e-shop application, so the amount of loyalty points gets sync'ed on both servers.
Is there any way how can I send http and/or xml/rpc request from SQL Server via either trigger or stored procedure (I suppose trigger can trigger a stored procedure, so either of these is fine)?
Is it essential to interface with the MySQL DB via xml/rpc?
I might try to accomplish this by linking the MySQL DB to the MSSQL DB... the process will be version dependent so your MSSQL version is helpful...
But this site:
http://www.infi.nl/blog/view/id/4/How_To_MySQL_as_a_linked_server_in_MS_SQL_Server
may be a good start for you
EDIT: And here, for MSSQL2008
http://dbperf.wordpress.com/2010/07/22/link-mysql-to-ms-sql-server2008/
I want to save any kind of log/tables with every query executed by my application.
I know I could do this by coding it (before I make any query, I insert a new row in a log table with the query and the user who is executing it.
I have read it can be done automatically but I'm not sure how can it work with WCF Services. I mean every query is going to be executed by the same SQL user and this wouldn't be very useful for audit operations (I need to know WHO made every query, and users will be validated against my own users tables).
Have you ever had a similar scenario? Thanks in advance!
As a starting point it may be worth looking into doing this via SQL Server Profiler. You can normally find this in the Tools Menu in Management Studio.
You can set up a trace to capture all SQL run on a server. More importantly you have a myriad of filter options which can be applied so that you only capture the data you are interested in (e.g. DatabaseName, UserName).
This information can be stored directly in a SQL Table, which should give you the abillity to join onto. Of course running anything like this will result in some overhead on the SQL box.
You can try the SQL Server Audit feature. It audits singe or groups of events both on server and database level. However, be advised that the database level auditing is available in SQL Server Enterprise and Developer editions only