How to update record in database from web application? - servlets

I am trying to do a assignment. I want to insert data into MySql from a .jsp page. Data are
ID, First Name and Last Name.
What i understand is I need to create a Input.jsp page where i can input ID, First Name and Last Name and take these values to servlet page and update my table in MYsql.
Does any one know where i can find this example? I am using Jdbc, tomcat and mysql.

First off, be advised that accessing your database directly from JSP is not a good practice. For ease of maintenance you're better off implementing your business logic and database access code in Java. Your JSP's should contain code to display the UI and nothing more. Hopefully your future assignments will have you do this.
Here are two tutorials that will help you with accessing MySQL via JDBC from JSP: JSP - Database Access and Connecting to MySQL database and retrieving and displaying data in JSP page.

Related

Copy some entries from one server database to other server database using asp.net mvc

We are doing some CRUD operation in DEV environment and data is saved in database. For other environments(like Staging/Prod) we want to copy those records from DEV database and paste to Staging/Prod when required using asp.net MVC. Is it possible? Could you please suggest some pathway in order to accomplish this?
You can accomplish this using a linked server:
https://learn.microsoft.com/en-us/sql/relational-databases/linked-servers/create-linked-servers-sql-server-database-engine?view=sql-server-ver15
This involves creating a link between one database server and another (they must be able to see each other on the network). You can then reference the linked server like this:
INSERT INTO [LinkedServerName].[Database].[dbo].[Table] (......
Alternatively you could use a paid for tool like SSMS tools which can generate insert statements on a per table basis: https://www.ssmstoolspack.com/

Dynamic Data to external database asp.net

I'm stepping through a walk through which allows me to create a dynamic data website.
Though in all the tutorials, including the one above, they all point to a local file based database. I need to add an external data model.
How could I add an external data model to the project? (A database hosted on a seperate SQL Server)
I've tried connecting through the SQL Server Object Explorer then dragging it into App_Data, but that didn't work.
Use the connection string in the web.config, but as you add the EF data model you should be given the opportunity to select you database by browsing for it.

asp.net with connection to sql server 2008

i am new in using asp.net language and i try to edit code asp.net which is already connected to a database on iis server
the problem that i faced is:
i can retrieve all table that already exist on that database but when i add new table i cannot retrieve it on asp.net "not found"
the same problem when i add new column all already exist column , i can retrieve them except the columns that i added them
but when i edit record , the record updated on asp.net so the problem when i create any thing or alter name of a column
thanks in advance
What sort of data access technology are you using? ADO.NET Entity Framework (one with .edmx file) or ADO.NET (one with .xsd)?
If you are using one of these you need to refresh or add tables in these diagrams too. Otherwise please get your code here so that picture gets clearer.

linq to entities 3.5 across multiple databases in same engine

What do i need to do in order to be able to query across multiple databases which are in the same db engine?
I have added the .edmx file of 1 database, but i only need 1 view from another db.
Thanks in advance!
Here are a couple of options:
Depending on your database platform, make the view from your second database available in your first database. If you're using SQL Server, you can use a linked server. If you're using Oracle, you can use a DB Link. Simply create a view in your main database where the view's select statement utilizes the linked server or db link to reference the view from your second db.
Create a second .edmx file for your second database. This is the route I chose recently. However I was dealing with one SQL Server DB and one was Oracle DB. There were also multiple tables and functions from both being used. I determined that it was cleaner in my case to create two separate data access projects, one for each DB, each with it's own .edmx.
Hope this helps.

How to create a database and populate it during setup

I would like to find a way to create and populate a database during asp.net setup.
So, what I'm willing to do is:
Create the database during the setup
Populate the database with some initial data (country codes or something like that)
Create the appropriate connection string in the configuration file
I'm using .NET 3.5 and Visual Studio 2005, and the Database is SQL Server 2005.
Thanks in advance.
If you are creating an installer I'm sure there is a way to do it in there, but I am not all that familiar with that.
Otherwise, what you might do is the following.
Add a application_start handler in the Global.asax, check for valid connection string, if it doesn't exist, continue to step two.
Login to the server using a default connection string
Execute the needed scripts to create the database and objects needed.
Update the web.config with the connection information
The key here is determining what the "default" connection string is. Possibly a second configuration value.
Generally, you'll need to have SQL scripts to do this. I tend to do this anyway, as it makes maintaining and versioning the database much easier in the long run.
The core idea is, upon running the setup program, you'll have a custom action to execute this script. The user executing your setup will need permissions to:
Create a database
Create tables and other database-level objects in the newly-created database
Populate data
Your scripts will take care of all of that, though. You'll have a CREATE DATABASE command, the appropriate CREATE SCHEMA, CREATE TABLE, CREATE VIEW, etc. commands, and then after the schema is built, the appropriate INSERT statements to populate the data.
I normally break this into multiple scripts, but YMMV:
Create schema script
"Common scripts" (one for the equivalent of aspnet_regsql for web projects, one with the creation of the Enterprise Library logging tables and procs)
Create stored procedure script, if necessary (to be executed after the schema's created)
Populate initial data script
For future maintenance, I create upgrade scripts where a single script typically handles the entire upgrade process.
When writing the scripts, be sure to use the appropriate safety checks (IF EXISTS, etc) before creating objects. And I tend to make mine transactional, as well.
Good luck!
Well, actually I found a tutorial on MSDN: Walkthrough: Using a Custom Action to Create a Database at Installation
I'll use that and see how it goes, thanks for your help guys, I'll let you know how it goes.
If you can use Linq to Sql then this is easy.
Just import your entire database into the Linq to Sql designer. This will create objects that describe all objects in your database, including the System.Data.Linq.DataContext derived class that encapsulate the entire database setup.
Now you can call DataContext.CreateDatabase() to create the database.
See here more information.

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