Multiple (Distinct) Databases With OpenSessionInView
Aug 11, 2010
In my web application, I have 2 totally different databases - one that's being used mostly by a CMS from which we'd like to get page information on non CMS pages on the same website, & one that contains totally different data. Is it possible to use Spring.NET's Open Session In View module with multiple session factories for both of those databases, so in this case I have 2 objects defined in spring.config of type Spring.Data.NHibernate.LocalSessionFactoryObject?
I would like to select a distinct query based on three fields and display the rest of the fields. For example,
I have firstname, lastname, address, city, state and zip, but I only want to use the distinct on these fields first and last name. However when i use the distinct function I get a distinct on all the selected rows. I just want to distinct firstname and lastname and display the other fields. for example,
Mary Smith New York Mary Smithy New York Mary Smith Maine
I would like the result to be:
Mary Smith New York Mary Smithy New York
I don't care about Mary Smith Maine, because i am only using the distinct for "Mary Smith" firstname and last name and showing the city.
i want to develop a data access layer ,it can support multiple database like oracle ,Mssqlserver and Mysql using enterprise library and C#.net 3.5 based on database connection
I am trying to design my logic to do this but I want to create a dataSet which will have records from several databases, The records all have the same layout.
I am reagin the connection string paths from a table in a database.
I am asking for your help in trying figure out my logic.
Should I use the connectionString builder in conjunction with a loop to Connect, read a record into a dataset Until therer are no more records to be read from my databse table with the database name/paths tables ?
Here is my beginning code which deals with one database:
I have to update multiple row and two column of each row.
I have try to Update with case statement but after I perform that statement it blank out every other column that doesn't fall into the criteria of the update statement.
My table structure is like this;
table1 col1 row1 11 row2 22
I want to update row1 and row2 of their col1 in one single sql , how do i do that?
One is adding Userdetails(Fn Name : AddUserDtls) and another one adding address details(Fn name : AddAddresDtls) based on UserName which will get added after execution of first method ie AddUserDtls.
Problem I am facing is :
I have a single transaction and in that I have all the methods.
After the execution of first method,with out commiting i will go to second method.
and if any error occurs in second method.
I will rollback everything including the changes made by first method also.
Here one issue is there.
Since I am not committing the changes made by first method,
While I am executing the second method I am getting error that 'No user Name exists'
I understood that if we commit the transaction before the second method starts ,it will solve the issue.
But then it creates another problem.If some problem araise in the second method,then I cannot rollback the changes made by first method since it aleready commited.
Is it better for a collection of ASP.NET web apps to share the same session database, or should each one have its own? If there is no significant difference, having a single database would be preferable due to easier maintenance. Background My team has an assortment of ASP.NET web apps, all written in either Monorail 1.1 or ASP.NET MVC 1.0. Each app currently uses a dedicated session state database. I'm working on adding a new site to that list, and am debating whether I should create another new session database, or just share an existing one with another app.
I am supposed to develop an enterprise-class ASP.NET Web Application that connects to multiple databases. For example when the web form loads, I should populate different ASP.NET controls (GridView, DataPager, TextBox, DropdownList etc) from multiple databases (SQL Server, Oracle, DB2, SAP Server etc) and also, edit the data in the controls and save the data to the respective databases on button submit.
Should I use Web Service or WCF for data integration, if so is there a limit on the size of the data?
What should be the architecture considering the application should be scalable and easy to maintain?
I am using mysql as my database.From one of my web pages I want to insert data to 4 tables.All the data should be inserted to these different tables on a single button click from the web page.How can I achieve this?Which is most reliable way to insert data to multiple tables on a single click event?
Will the sql operation with 4 'insert' statements separated by semicolon work for me?
I have a quick question about best practices and especially expected performance for the following scenario:
If I want to query data from multiple servers that contain schematically identital sql databases, would having each server provide a web method that a single client application can consume be an appropriate (and relatively fast) solution?
The data just needs to be consolidated on the client end, where several web methods would have to be consumed serially (or in parallel?) to provide the data to the client. Each server would also be implementing Entity Framework as an ORM.
Performance is my main concern here, would it turn out excessively slow as we start to scale up to more and more servers?
I'm currently working on an C#/ASP.NET project that will host several differents e-commerce websites, all running in the same application.I use LinqToSql (moving to PLINQO soon) to access my database. The database contains both informations on the website structure (pages, ...) and the products/orders/users data.
My question is, should I use only one database for all the websites, or sould I create a new database (same model) for every new website?I'm now using a single database (with SiteIDs in some tables) but I have a big security concern, I can't just backup/restore the database for ONE website if something goes wrong (e.g. somebody erase all the products on ONE website) and it's an important requirment of the application.
So I was wondering what are the good practices in that case? Is there big cons if splitting dbs?(I would have to make changes to several database instead of one in case of structural changes, but i guess i can make a db version/update system).How the existing CRMs are dealing with that?Is it a performance problem if a database server host a lot of different DataBases? A complex backup/restore tool would be better?
Subquestion:To make a website replication easy, I can also split the pure CMS data (Pages, Texts, ...) in one DB and the e-commerce data (products/categories/orders in another). It can be achieved by some select/insert functions but it would be easier by just copying a database of course.
Consider that I want to create 10 websites in IIS, each of them pointing to the same website on local hard drive, each one running the same code, but on different subdomain.subdomain1.domain.com, subdomain2.domain.com, ..., subdomain10.domain.comHow can I add multiple connection strings in my web.config file and bind each connection string to a different subdomain ?I want to do this because every website will have a different database with different data.
i got the different datatable value using different query.Now i want to export to excel at the single sheet like datatable1 to sheet1 and datatable2 to sheet2 .
I have a query which gets values from two tables which are in different databases.How can I write a SINGLE Connection String which connects to two databases? By the way I am using SQL Server Database
I'm working in an environment where a single web application (running in a web-farm) dynamically connects to different SQL Server databases (possibly on different servers) based on user selection (this part is non-negotiable, unless you can gift me $1,000,000 and/or some kind of time altering device).
I'd like to cache some of the commonly used data from the database(s) in the application, such as "settings", and am looking for a best practice to use with the SqlCacheDependency class or a related database cache dependent solution (not opposed to a custom implementation of SQL notification or polling; notification is preferred over polling).
So far, I'm thinking of using a collection of SqlCacheDependency objects (one for each database) that can be referenced by connection string name or related key. So when the connection is changed to a different database, the cache can be requested/populated by a key of <databasekey>+<datakey> and use the appropriate SqlCacheDependency object (probably handled by a cache-managing wrapper).Or is it just better to take the hit and always go to the database?
