How to update a table in database using LINQ in F#?
I have seen plenty of examples on how to query the database but nothing on how to update records. Below is the simple code that I wrote to retrieve a table, but can someone explain me how can I modify a field, say lastActiveDate, and update the table on the database
Thank you, suday
open System
open Microsoft.FSharp.Linq
let connString = "Server=localhost;Database=myDb;Trusted_Connection=True;"
let db = new MyDb(connString)
db.Log <- System.Console.Out
let res =
Query.query <@ seq {
for u开发者_开发百科sers in db.userAccounts do
yield users
} @>
|> List.ofSeq
printfn "Totla users: %d" res.Length
Since MyDB is a System.Data.Linq.DataContext, it tracks each object that it loads. Simply acquire an instance from MyDB, set a property's value on that instance, and call MyDB.SubmitChanges
LInQ (in any .NET language) is not used for doing insert/update/delete operations. After all, it Language Integrated Query. That having been said, in your example the db
value should have methods for passing modified objects back to the database for persistence.
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