What concepts/steps shall i need to learn to access a central database(server). The system will have a software(manipulate by users) which access the database in the server. System like inventory systems, billing, etc..
First of all you need to know vb/C#.net (which I assume you know). Next you must be able to write SQL queries, stored procs, T-sql, etc. to communicate to the database. Finally you need to know ADO.net to communicate between your application and database.
You can start your ADO.net study from here:
http://msdn.microsoft.com/en-us/library/e80y5yhx.aspx
http://www.codeguru.com/vb/gen/vb_database/adonet/article.php/c15033
Here is a link which will help you under stand the data access layer: http://msdn.microsoft.com/en-us/library/aa581778.aspx
Hope this helps...!!!
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I work in my companies small IT department. I have been creating automation via VBA in Excel to pull data from SQL and put it into Excel, then dynamically format and summarize the data. The issue I am running into is the IT department does not want to give anyone outside the IT department SQL Read-Only Access. They view SQL as a privilege not a right...even if it is only Read-Only. They claim security reasons.
Just to be clear, we are NOT installing SQL on these peoples' computers nor do they have the technical understanding on how to write queries. Also, they can already view all the information on the front-end website.
I currently have to specify which database and which tables they can have access to and it takes about 1-2 weeks to give them access (they drag their feet doing the requests).
I am not trying to vent, I am actually wondering do they have a legit concern about security and is this actually a best practice on their part?
The worst thing that could happen is a user knows just enough to connect MS Access to the database, write some poor queries, and grind everything to a halt. You should always have non-IT users access data in a safe, structured way. Especially if this database is a transactional one, and not a reporting database.
Sure, they can access all the data per business process. So then, create a nice, safe query to read all the data and dump it to Excel - if that's what the users want.
Otherwise, IT-created queries - preferably in Stored Procedures - should be reading the data and presenting it to the users.
So it's not a security issue per se. It's more an issue of "we don't want non-IT users getting crafty and bringing down the database with poorly written queries."
I believe the connection properties to the SQL server is embedded in your VBA code, as long as the code is not visible to the user then there is no way they can query the SQL server directly.
Sounds like you need an SQL read only service account which you can use for Query connections. Create an Excel data connection that has the security details to connect to SQL, then your VBA hooks into that data connection.
I am currently creating a vb.net program in which users upload a song file to the program and then it is saved within the programs files. I have set up the actual saving of the files but would also like to store some meta data of each in a SQL database within my program.
I have looked online and although i now understand the basics of SQL, im still a little fuzzy on how you actually implement this within VB.net. I have already added the library- Imports System.Data.SqlClient but failed to work out how to begin coding in SQL.
The basics of what im trying to acheive is a if statement that will determine wether or not a SQL database has been created in a specific location, and if it hasnt it should create it.
All constructive answers appreciated, thanks.
There are a number of different database engines available. The namespace that you have chosen contains the ADO.NET client classes for Microsoft SQL Server. You would use a connection string to specify how to connect to the database. This would often contain connection information, such as server name, user name, password etc, but it sounds like you want to store data locally.
There is a local version of SQL Server called LocalDB, but I think you would still need quite a lot of the SQL Server components installed for that to work. Although you can package these with your application they may be too large for you, so you may want to look at SQL Server Compact Edition, which is much smaller and allows you to package the whole engine as part of your application and is useful for storing data locally. Compact edition doesn't have quite all of the features that LocalDB does, so you may want to compare the features available for each.
Although you can use the ADO.NET objects to connect to a database, I think most people these days would use a layer on top which transfers data back and forwards between objects in memory and the database. This also allows you to use Linq to query the database in most cases. I personally use Entity Framework. You might want to look into that. There are different ways of configuring EF so you may want to look at a tutorial. Once you have it set up, you will probably find it much easier and safer to work with than writing SQL manually though.
We have a 3gb file of data from our propriartary CRM system which is using SQL as a database.
The CRM is not meeting our needs and we are thinking about moving to Microsoft access and building our own system from the start.
We were wondering if it is possible to easily migrate the SQL database into access?
Thanks for your time.
First of all, it has been a long time since I've had to use MS-Access (thankfully) but I'm not sure Access is suitable for databases of that size. In my opinion, it's best suited to small, desktop-type applications with few concurrent users.
To answer your question, I believe Access offers a data import feature(see under the External Data ribbon in 2013) - though I'd suspect it might balk at the idea of 3GB of data. Edit: Actually this link suggests the max databsae size is 2GB
What might be more useful however, is its Linked Table feature. If I remember correctly this allows you to access data stored in SQL Server (or a similar RDBMS) which is more suited to large volumes of data through an Access front end - complete with pre-canned forms, queries, reports etc..
It is possible and fairly straight forward to move all of your data tables from SQL Server to Access; however, SQL Server is a much more robust database engine than Access. I would highly recommend against that. I have however had very good success using Access (ADP project files) as a front for the interface and using SQL Server as the database back-end for simple to moderate complexity interfaces. If you are not getting the performance you desire from your SQL Server, you might want to consider query performance tuning and looking into memory and hardware upgrades first. I think you will get better and faster results from doing that.
The simple solution would be to “link” Access to SQL server. That way you continue to use a robust data engine, but are free to use all the reporting and coding features of Access.
In this setup then Access simply becomes a “front end” to the existing SQL database.
And you do NOT want to use an ADP project in Access since they are depreciated.
The process is thus to create a blank standard database, and then use linked tables to SQL server. This will not only eliminate the need to import data (which is likely changing all the time).
My database must be updated at arbitrary intervals, manually, with new info to put on standart tables that don't require structural modifications. one app will update the database.
Another app, the one I will distribute (to friends and family only, but doesn't require any security feature to it, like encrypting the database) will read the database and use its data on labels, listviews, etc.
The problem is, I'm the perfect definition of full-fledged n00b at programming of any sort, and still don't know what database to use.
I thought that I should use a SQL CE (*.sdf) file, and store that database thing on an FTP. then, I could download it and get data from it everytime the "client" app runs, and certain button ("connect") is clicked.
After some hard-core googling, I found out how to connect to the sdf thing, using this connection string:
Provider=Microsoft.SQLSERVER.CE.OLEDB.3.5;Data Source=D:\Documents and Settings\Camilo\JCTM.sdf
So it connects, or at least didn't show any error.
I don't know if it's a good idea to use sdf SQL CE files as databases, if it's too hard maybe I should go for XML? what do you guys suggest, what is the easiest way to implement very simple databases in VB.NET?
By simple databases I mean:
- no search needed
- no advanced features except storing strings on tables with columns and rows
- easy to access, read, edit, etc. by different VB.NET apps
Is sdf a good idea?
I would recommend Sql Server Express Its free and can be redistributed with .net applications as part of the install process.
The challenge will be syncing the changes between the different clients. If you have access to a FTP server, you may have the ability to host a website in IIS. If you can do that you can just use webservices and read against one database instead of copying one local.
Luckily for you, you can abstract away the need to be concerned with which back-end database you use to store your data.
Technologies such as ODBC (Open Database Connectivity) and OLEDB (Object Linking and Embedding, Database) allow you to limit your concern for the backend datastore to the task of crafting your connection string. In your example, the connection string says, "I'm going to connect to a SQL Server CE database via its OLEDB provider, and it's physically located over on D:/...
Within the code, you use standard OLEDB mechanisms to access and manage the database. Because of this abstraction, you can use OLEDB providers for SQL Server, Oracle, XML, Access or comma delimited text files as your backing store if you wish, and the only change you need to make to your code is the connection string. Your choice then should be to pick the database that you have the tools and know-how to set up and manage initially.
I'd start with Microsoft Access because it has its own UI, and can play well with .NET.
You can also try the ADO.Net implementation for SQLite, which I've also found very useful.
Is this possible?
We have a Configuration Management Database that stores information such as our servers, what datacentre they're stored in, applications that reside on them, as well as interfaces that send data from one application to another.
We would like to use Visio to connect to our SQL 2005 database, and automatically generate a flow diagram that details these dependancies and relationships.
So again - is this possible? If so, does anyone know of some documentation that details how to do this?
Is this what you are looking out for?