C# - Create A Database That Can "add", "remove" And "edit" Tables And Columns?
Oct 19, 2010
What would be the best database/technique to use if I'd like to create a database that can "add", "remove" and "edit" tables and columns? I'd like it to be scaleable and fast. Should I use one table and four columns for this (Id, Table, Column, Type, Value) - Is there any good articles about this. Or is there any other solutions? Maybe three tables: One that holds the tables, one that holds the columns and one for the values?
Maybe someone already has created a db for this purpose? My requirements is that I'm using .NET (I guess the database don't have to be on windows, but I would prefer that)
What would you all suggest a database with less number of tables and more number of columns or more number of tables with less number of columns. I am developing a web application using Visual stuio 2005 and Sql Server 2005
I want to know that how many tables we can have in database and what is the maximum no. of columns.I also want to know the maximum size for each datatype.
I am developing the Home page of a Client. Apart from various things on this home page I have a text box and search button. Having said that, I have a database in which I have almost 12 tables with varying number of columns. Now my question is,Is there anyway to search a word typed by a user in the textbox to search it in all the tables(all columns) of the database.
I have two SQL Server tables with Primary Keys (PK) and a Foreign Key (FK) linking the two tables:
1) Table "Order"
OrderID, int, PK AddressID, int, FK ...
2) Table "Address"
AddressID, int, PK City, nvarchar(50) ...
Then I've created an (ADO.NET) Entity Data Model out of those two tables. Now on my (ASP.NET) webpage I put a GridView with an EntityDataSource. In my GridView I want to display two columns:
OrderID City (belonging to that order and linked by the AddressID-key) How can I do that? My problem is: When I configure the Entity Data Source I can select an "EntitySetName" which can be either "Order" or "Address" but not both, nor can I select any kind of relationship. If I select "Order" as EntitySetName then in the GridView I can add the columns
OrderID Address Address.AddressID
Adding the column "Address" displays empty cells. Adding "OrderID" and "Address.AddressID" displays the expected IDs. But how can I add the "City" of the related address to my GridView? Edit: Clarification:
The Entity Framework has created a class "Order" and a class "Address" corresponding to the database tables. The class "Order" has a reference to an "Address" object as a navigation property, corresponding to the 1-n relationship between Address and Order table. Basically I want to have a column in my GridView which displays Order.Address.City. I have tried to add a bound field with "Address.City" as data field to the GridView but it results in a runtime error ("no such property...").
I'm working on a new asp.net 4.0 resume web site. I'm starting off with SQL Server Express 2005 and using the standard security and login features given with ASPNETDB.mdf. My site will be hosted on GoDaddy.com.
Quesiton. Should the tables that will contain the information that users will be putting in like resumes, contact information and such go into ASPNETDB.mdf or should it go into a separate database.
I have an ASP.net security database which is normally ASPNetDB.MDF however I have created the same database structure in MS Access. All works great. However, I need to add a couple of other tables but I can't find how to do that in VWD. I'm pretty sure I was able to when the first database I created was an MDF file but not in MS Access.
I have a user requirement to hav the ability to directly edit the gridview without having to click the edit link. I was thinking of showing dropdown lists for each column-to-row so that the user can select the values for each record. Then the table will be updated accordingly (no update link).
Is this possible or do I still need the edit template and specify the item template with the dropdown list?
I have used a microsoft tool before that was allowing me to automatically generate admin web pages from database tables. By admin web pages I mean pages that allow me to do CRUD operations on my tables.
I am working on a multi-lingual application Assume the following:
Database has 50 tables and application has to support 5 languages
Which is the best way to design the database:
1. Include a langugae column for each table. Repeat the values for each language. Say i have a country table which has 100 countries in it. Then my design will contain 500 rows (100 for each langugae)
2. Create a separate table which will contain the translations for all the 50 tables in with a foreign key to the parent table.
Is there some way to remove data about all users , roles e t c from some Web application into aspnet database tables? tables like dbo.aspnet_Applications (here is this application that I want to remove) but also I need to remove all data with this application in other tables.
I created a gridview that is made up of 4 gridviews and using a stored procedure to populate it. I create columns at runtime because the number of columns changes all the time.To make the grids editable I am adding template fields at runtime as I create the columns, this is to ensure that a user is able to edit the cells and some foot values update. Reason why I have four grids is to freeze rows and columns like in excel using javascript. The problem is that performance is very bad especially in IE, the grids take a long time to load. I am not sure if this is caused by the data load or the creation of text boxes. see some of the code below for my _aspx page:
using sql server 2005 and vb.net 2005. I am writing a console application to import a mass amount of data from a non-sql database table into a sql server database table. The destination db table (sql server) has fewer tables than the source db table so I need to map the columns. does anyone have an example of how to do this?
I have a partitioned db where several tables have the exact same structure. I'm able to query the tables using linq, but only by quering the individual tables 1 at a time and by using the explicit table name. For example at the moment, I have 8 tables so I have something similar to the following:
[Code]....
Is there any way, that based on a certain value (stringValue), I could determine which table to query and then code the linq query just once?
is there an easy way to compare two columns in two datatable to see if they match? I need to check if the values in column["x"] of datatable1 occur in column ["y"] of datatable2, without iterating through both tables (for each value in column of dt1, check column of dt2). I tried:
foreach (DataRow dr in dt1.rows)
if (dt2.rows.find(dr["x"]) but this checks the whole row and if finds an "x" in any column, "if" condition is true. I need to only check one column of dt2. Tables have different columns but the same primary column and that's what I need to check
Entity ID (PK), int Name Descrip Users ID (PK) EntityID, int (this is not connected to Entity table)
Now I am using LINQ to pull the records which has a Entity.ID = something. Which will show me couple of records in my GridView. Here is my LINQ statement:
protected void Page_Load(object sender, EventArgs e) { string getEntity = Request.QueryString["EntityID"]; int getIntEntity = Int32.Parse(getEntity); OISEntityTestingDataContext db = new OISEntityTestingDataContext(); //OISLinqtoSQLDataContext db = new OISLinqtoSQLDataContext(); var tr = from r in db.Users join s in db.Entities on r.UserID equals s.ID where s.ID == getIntEntity select new { //To Show Items in GridView! }; GridView1.DataSource = tr; GridView1.DataBind(); }
Now here I am getting an error mesg on 'join' The type of one of the expressions in the join clause is incorrect. Type inference failed in the call to 'Join What does that mean?
I need to join some tables to get the matching records. I often have to ask around to see how certain tables could be joined. Is there any way to query the information schema or some thing else to see what columns/values match in certain tables in order to figure out how tables should be joined.
I want to merge those with a single table ( Fields:PersonID, FirstName, LastName, Role, Department, Unit). How can I query to accomplish this so that same personID data go to same row ? ANY QUERY ?? (I have an idea : both export to excel and merge into a single excel file and import to SQL table but due to very long data it was truncated last time when importing so I don't want to reimport again.)
I have a .net code that generate a nested grid kind of output. I have written the logic to to generate the nested grid in prerender. The use html tables to generate the same. I need to align all the columns in the grid.
How can I align the columns of nested tables for the following HTML code. I want all the columns from all nested tables to be aligned. I will use that logic then in my prerender.
