How to use list values to update table column in a database?

Question

Welcome, I have a string list populated with some encryption keys. I want to use these keys to decrypt values in a column in a database (the first key in the list decrypts the first column value). How to do that??

Sreekanth Reddy · Answer

Hi Samia, From your requirement : Firstly loop the keys or loop the total records which you bring from database. Here you should be sure that each key needs to point the specific value of each row in database. For ex: If total keys 10 - Then total records to be 10. So that we can map each record value with its key. Firstly bring all the column values to datatable or dataset. Let us think that "ds" is having the values. Later loop the total list of keys. for(int i=0;i { // here comes our logic. var keyIs = str[i]; var valueIs = ds.Tables[0].Rows[i]["columnName"].ToString(); //Now we have both key and value. } Hope you understand. If it helps mark as answer. Thank you.

Samia Souror · Answer

Hi Srikkenth, Thanks for your help. It worked perfectly

Mehreen Tahir · Answer

Well, in that case you need to share the algorithm. It's hard to guess what exactly is going on when I don't know the database you're working on neither the algorithm. Or you want algorithm from us? Besides this stackoverflow thread might be helpful. https://stackoverflow.com/questions/48423632/encrypt-decrypt-columns-without-changing-existing-functionality

Samia Souror · Answer

I have my own algorithm to encrypt/decrypt encrypt(plaitext,key) decrypt(plaitext,key)

Mehreen Tahir · Answer

It would have been great if you had mentioned which database you're using. Anyhow, you can use DecryptByKey (Transact-SQL) function. It can be applied to SQL Server and Azure SQL database. DecryptByKey ( { 'ciphertext' | @ciphertext } [ , add_authenticator, { authenticator | @authenticator } ] ) You can also check the detailed documentation here. Hope that helps.