Question

我有以下F＃代码

open FSharp.Data.Sql
open FSharp.Data.Sql.Runtime
open System.IO

[<Literal>]
let private schemaConn = @"Driver={Microsoft dBASE Driver (*.dbf)};DriverID=277;Dbq=C:\Citect\User\NPM;" 
type private schema = SqlDataProvider<Common.DatabaseProviderTypes.ODBC, schemaConn>
let private connStringFormat = Printf.StringFormat<string->string>(@"Driver={Microsoft dBASE Driver (*.dbf)};DriverID=277;Dbq=%s;")

type internal Project = {
    name : string
    path : string
    dcx : schema.dataContext
}

[<Literal>]
let private cUserPath = @"C:\Citect\User"

let private findPath projectName = 
    Directory.GetDirectories(cUserPath, projectName, SearchOption.AllDirectories)
    |> Array.find (fun d -> d.Contains("web") |> not)

let internal connect projectName =
    let path' = findPath projectName
    let connString = sprintf connStringFormat path'
    let dcx' = schema.GetDataContext(connString)
    { name = projectName; path = path'; dcx = dcx' }

let internal updVariable (project : Project) variable = 
    let dcx = project.dcx
    let q = query {
        for v in dcx.Dbo.Variable do
            where (v.Addr = "%MW217.0")
            select v
            exactlyOne
    }
    q.Addr <- "QQQ"
    dcx.SubmitUpdates() //error

let internal prj = connect "NPMUG_SCC35"
updVariable prj ()

连接和查询按预期工作，但是当我尝试更新数据源时，我收到来自odbc驱动程序的以下错误：

消息 - ＆gt;错误[HY092] [Microsoft] [ODBC dBase驱动程序]无效属性/选项标识符来源 - ＆gt; ODBCJT32.DLL

有没有办法让它工作或者我是否需要放弃类型提供者并回归OleDb？

更新

禁用事务使事情变得更好，现在错误是由于我必须使用的dbf文件中缺少主键。

唯一改变的代码是获取数据上下文

let dcx = schema.GetDataContext( { Timeout = TimeSpan.MaxValue; IsolationLevel = Transactions.IsolationLevel.DontCreateTransaction } : FSharp.Data.Sql.Transactions.TransactionOptions)

新错误是：

System.Exception：错误 - 您无法更新没有的实体   有一个主键。（dbo.variable）at   FSharp.Data.Sql.Providers.OdbcProvider.createUpdateCommand（的IDbConnection   con，StringBuilder sb，SqlEntity实体，FSharpList`1 changedColumns）


at。$ Providers.Odbc.FSharp-Data-Sql-Common-ISqlProvider-ProcessUpdates @ 648-4.Invoke（SqlEntity）     吃     Microsoft.FSharp.Collections.SeqModule.Iterate [T]（FSharpFunc 2 action, IEnumerable 1 source）at at     FSharp.Data.Sql.Providers.OdbcProvider.FSharp-DATA-SQL的共ISqlProvider-ProcessUpdates（的IDbConnection     con，ConcurrentDictionary 2 entities, TransactionOptions transactionOptions, FSharpOption 1超时）at     。$ @ SqlRuntime.DataContext.f 1-69（SqlDataContext     __，IDbConnection con，Unit unitVar0）at FSharp.Data.Sql.Runtime.SqlDataContext.FSharp-Data-Sql-Common-ISqlDataContext-SubmitPendingChanges（）

有关如何处理此探测器的任何想法吗？

Answer 1

我发现了一种棘手/肮脏的方式，我将其分类为一种解决方法，而不是真正的解决方案，但它适用于我的情况;所以我将使用它，除非/直到其他人建议一个结论性的。

为了让类型提供者工作，我需要做两件事，而不是在通常的工作流程中：

需要在禁用交易的情况下检索数据上下文
在对DBF执行更改操作之前，我创建了一个主数据库使用较低级别的SQL语句键入该DBF

这里是工作代码

[<Literal>]
let private schemaConn = @"Driver={Microsoft dBASE Driver (*.dbf)};DriverID=277;Dbq=C:\Citect\User\NPM;READONLY=FALSE" 
type private schema = SqlDataProvider<Common.DatabaseProviderTypes.ODBC, schemaConn>
let private connStringFormat = Printf.StringFormat<string->string>(@"Driver={Microsoft dBASE Driver (*.dbf)};DriverID=277;Dbq=%s;READONLY=FALSE")

type internal Project = {
    name : string
    path : string
    dcx : schema.dataContext
}

[<Literal>]
let private cUserPath = @"C:\Citect\User"

let private findPath projectName = 
    Directory.GetDirectories(cUserPath, projectName, SearchOption.AllDirectories)
    |> Array.find (fun d -> d.Contains("web") |> not)

let private createPK (cn : IDbConnection) = 
    let cm = cn.CreateCommand()
    cm.CommandText <- "ALTER TABLE Variable ADD PRIMARY KEY (Name)"
    try
        cn.Open()
        cm.ExecuteNonQuery() |> ignore
    finally cn.Close()

let internal connect projectName =
    let path' = findPath projectName
    let connString = sprintf connStringFormat path'
    let transOptions = { Timeout = TimeSpan.FromSeconds(3.0); IsolationLevel = Transactions.IsolationLevel.DontCreateTransaction }
    let dcx' = schema.GetDataContext(connectionString = connString, transactionOptions = transOptions)
    dcx'.CreateConnection() |> createPK
    { name = projectName; path = path'; dcx = dcx' }

let internal updVariable (project : Project) variable = 
    let dcx = project.dcx
    let q = query {
        for v in dcx.Dbo.Variable do
            where (v.Addr = "%MW217.0")
            select v
            exactlyOne
    }
    q.Addr <- "QQQ"
    dcx.SubmitUpdates()

let internal prj = connect "NPMUG_SCC35"
updVariable prj ()

F＃SqlProvider无法使用ODBC连接更新dBase DBF文件中的更改

1 个答案: