Beginner's question about getting query lists

Hi, I am using Npgsql.FSharp to create an API using SAFE.

I was able to connect to the database and generate records randomly. However, I fail when I try to select all records from my table.

Consideing my “table” as this type:

type Market = {
    Id : int
    Pair : string
    Quantity : int
    Price : float
}

Then, I created another type to manage my database, as well as members. Similar to the example with LiteDB/default from SAFE. A fragment from code is as follow:

type DbNpgsqlStorage() =
    let connectionString : string =
        Sql.host "localhost"
        |> Sql.database "postgres"
        |> Sql.username "postgres"
        |> Sql.password "postgres"
        |> Sql.port 5432
        |> Sql.formatConnectionString

    member __.GetMarkets () =
        connectionString
        |> Sql.connect
        |> Sql.query "SELECT Id, Pair, Price, Quantity FROM market"
        |> Sql.executeAsync (fun read ->
        {
            Id = read.int "Id"
            Pair = read.text "Pair"
            Price = read.double "Price"
            Quantity = read.int "Quantity"
        })
        |> ignore

    member __.GetCountMarkets() =
        connectionString
        |> Sql.connect
        |> Sql.query "SELECT COUNT(*) as count_markets FROM market"
        |> Sql.executeRow(fun read -> read.int "count_markets")
        |> function
            | Ok count -> count
            | Error e -> 0

The question is: considering GetMarkets(), how can I get the list from the query? When I try to use ignore the result is a “unit”. I already used match but without success.

Similar problem I had on GetCountMarkets(), then, I used a bad workaround.

Sorry, I am learning F# and SAFE this week. I have never seen them before. Consequently, I do not know how to deal with F# Railway properly.

Every help is welcome 😄

[Zaid-Ajaj]

No problem, I am glad you were able to fix the problem. I will be adding better docs soon to help with these kinds of issues 😄

[jacksonpradolima]

I do not know why but it is working now! I guess I was trying before change the column names…sorry

Thanks a lot @Zaid-Ajaj !