F# Dapper how to create connection string.

[Guest zydjohn]

Hello:

I recently want to learn Dapper for F#, in order to access SQL Server database.

I found some article for this topic.

And I created a simple database [myDB] using SQL Server 2017, and created a small table:

 

USE [MyDB]

GO

 

CREATE TABLE [dbo].[users] (

[iD] [int] NOT NULL,

[FirstName] [nvarchar](30) NOT NULL,

[LastName] [nvarchar](30) NOT NULL,

CONSTRAINT [PK_Users] PRIMARY KEY(ID))

GO

 

Add some records:

INSERT INTO USERS VALUES(1, 'Jo', 'Jo')

INSERT INTO USERS VALUES(2, 'John', 'Doe')

 

Now I want to use someone's code to retrieve records from [users]:

 

module DapperFSharp =

open System.Data.SqlClient

open System.Dynamic

open System.Collections.Generic

open Dapper

 

let dapperQuery<'Result> (query:string) (connection:SqlConnection) =

connection.Query<'Result>(query)

 

let dapperParametrizedQuery<'Result> (query:string) (param:obj) (connection:SqlConnection) : 'Result seq =

connection.Query<'Result>(query, param)

 

let dapperMapParametrizedQuery<'Result> (query:string) (param : Map<string,_>) (connection:SqlConnection) : 'Result seq =

let expando = ExpandoObject()

let expandoDictionary = expando :> IDictionary<string,obj>

for paramValue in param do

expandoDictionary.Add(paramValue.Key, paramValue.Value :> obj)

 

connection |> dapperParametrizedQuery query expando

 

 

However, I can't figure out how to write the connection string.

And how to use his query helper to do something like in T-SQL, I can run the following query:

SELECT FirstName, LastName FROM Users WHERE ID = 2

 

You can install Dapper from Package Manager Console:

PM> Install-Package Dapper

 

I am using Visual Studio 2017 on Windows 10.

Please advise.

 

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