mysql - F# 连接到在线 MySQL DB 执行查询

Question

我正在制作一个 F# 项目，需要对在线 mysql 数据库进行一些数据库查询。谁能帮帮我吗。我需要这样的东西

    \\  Connect to DB
    let servername = "localhost"
    let username = "username"
    let password = "password"
    \\ Code that connects to db
    \\ Print error message if can connect 

    \\ Query 
    let query = "SELECT * FROM table ..."
    \\ Code that executes query 
    \\ Error Message if query not executed  

Answer 1

您应该为 MySQL 安装 .NET 驱动程序。然后安装 SQLprovider。文档中有 MySQL 的示例。您将连接到数据库并像这样查询它:

type sql = SqlDataProvider<
                dbVendor,
                connString,
                ResolutionPath = resPath,
                IndividualsAmount = indivAmount,
                UseOptionTypes = useOptTypes,
                Owner = "HR"
            >
let ctx = sql.GetDataContext()

let employees = 
    ctx.Hr.Employees 
    |> Seq.map (fun e -> e.ColumnValues |> Seq.toList)
    |> Seq.toList

connstring 将是这样的:

[<Literal>]
let connString  = "Server=localhost;Database=HR;User=root;Password=password"

您还应该阅读 https://msdn.microsoft.com/visualfsharpdocs/conceptual/walkthrough-accessing-a-sql-database-by-using-type-providers-%5bfsharp%5d