What doesn't work, and what more information about the problem do you have? Insert, Update and Delete part not working. Are the queries returning errors? Are you getting errors connecting to the database? What are the errors? I used VS But when I used VS13 to do. There have no option to create sdf database. So, I built it using mdf. So, That's the reason it's not working — yeshansachithak.
Add a comment. Active Oldest Votes. About your other questions. There is not a "best practice", you use one or another depending of your requirements. You can use an SQL script to create your database during installation process. Improve this answer. Oscar Oscar Thanks, I know. I've researched. Problem is, before deploy the application I have add some data to my database. Then I deployed.
I can see my data grid view that database data is their. When I insert the data it's working. This designer has a window divided into three parts. In the upper half we have the columns of our table with their data types and other important properties. Below is the resulting T-SQL code, which will run and create the database when we'll be finished. As we've already said, each entry in the database that is, a row in a table should have a unique identifier a column which value is unique for each row.
We use the primary key for this purpose. It's an ordinary column, most often named simply Id and will be of the int type. We'll write column names with the first letter capitalized. We'll also add 2 more columns: Spanish and English. This is the word in the Spanish and English languages. The columns will be of the nvarchar 50 type. This is a string where 50 is the maximum number of characters. Do not confuse it with the nchar type, where it wouldn't be the maximum size, but the text would be always 50 characters long.
There are also the char and varchar types without the n , these don't support Unicode encoding and therefore we won't use them. So we'll always use the nvarchar type for short texts.
Finally, we'll add the last column, Difficulty , indicating the difficulty of the word. It'll be of the int type. If the similarity of a database table and a C class crossed your mind, then you're right.
The definition of a table is almost identical to the definition of a class, we simply add properties which the given entity has. The rows written in the table can then be understood as individual class instances. So it's like we created a Word class, which had the Id , Spanish Spanish version and English English version properties.
We'll also work with the database like this, but let's not peek much further. Let's go back to the Id column, right-click on it and select Properties.
This determines that the Id column is always unique. This means that the first word in the table will have the value Id of 1 , the second 2 , etc. The database will automatically assign a higher Id to each newly inserted word, so it takes care of the uniqueness itself. Id s are still growing, even if we delete a word and its Id is released, it will no longer be used. This is because recycling old Id s would cause problems. If this column has not yet been set as the primary key for our new table, then right-click on the column name and select "Set Primary Key":.
Each table should have a primary key, otherwise we won't be able to identify a specific entry and some technologies e. Entity Framework could have trouble working with such a table.
Finally, we'll rename the table to Word. We'll achieve that by rewriting the current name Table in square brackets at the end of the first line in the T-SQL code. We name the tables in capital letters again and in singular, as if it was a class:. After renaming, we click on the "Update" button.
In the window that opens, we click on "Update Database" to save the changes. What is a local database? Next, Add the sql script below to create a new Customer table. Where is LocalDB stored? You can find the local database in the same directory of your project.
How to connect local database in c windows application? Customers' table. You can move, or remove it, as needed.
0コメント