How do I solve the deployment issues (mentioned in the previous FAQ)?

• The easiest and very sound solution is to provide the database script to create necessary database and tables along with the installation and ask your user to run the script on the target database server to create the required database. Then ask the user to supply the connection string at the installation setup time.
• You can create the database with the installation by executing the database creation script with the installation. But before this, you have to ask the user the location (the computer on the network) where the database server exists, and the user name, password to login to the database.
• The connection string should be stored in a text or binary or xml file. You can also encrypt the connection string before writing it to the file. The application, thus, is required to decrypt and load the connection string in the memory at each startup.
• The application should load the connection string at each startup and attempt to connect to the database. If the connection attempt fails then it should inform the user that the database is not available and ask the user to setup the database and try again. The application should also allow the user to change the database connection string any time and, it the application logic permits, let the user specify to work without database. If the user specifies a new connection string during the application startup or regular execution, the application should save it for later use.
• One solution to the schema changed problem is to use views and stored procedure wherever possible. But if this is not done or the change is too big to be catered by the views and/or stored procedure then you can supply a new data access module update (a new DLL may be). For this reason, it is advised to separate the data access code in a separate physical and logical module (or assembly in .Net language) so you can change it without affecting the overall application. But when using this, the interface (the method signatures) should be made that abstract that they does not exactly map to the physical database schema but to the logical schema. Finally, if the database schema change is major (which is not a very good sign for the application overall design) then there is no solution but to change the code and ship the installation again!!!

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