.NET - 在 Visual FoxPro 中使用 Entity Framework - 错误 "Compiled code for this line is too long."
.NET - using Entity Framework with Visual FoxPro - error "Compiled code for this line is too long."
我正在尝试将 Entity Framework 6 (EF) 与 Visual FoxPro 数据库一起使用（使用来自 NuGet 的包 VFPEntityFrameworkProvider2），我能够很好地建立连接。我能够从大多数表中加载数据。
当我尝试检索具有大约 240 个字段的特定类型的 DbSet 时出现问题。抛出的异常包含消息：
Compiled code for this line is too long.
据我所知，EF 编写了 SQL select 语句来检索数据，并且此语句太长。当我使用调试器检查局部变量时，我看到一个 SQL 语句，其长度接近 16000 个字符，而 maximum allowed command length for VFP is 8,192 bytes
我不太确定如何解决这个问题，因为我对 EF 还很陌生。我想我可以编辑一些生成的代码，或者编写一些自定义处理程序。也许我可以批量检索字段，然后组合对象。
此外，我相信可以将我的实体分解为类型和子类型；也许如果我这样做，一次只会检索一部分字段。
谁能建议我用什么方式解决这个限制？
添加的注释：
不能选择使用不同的数据库。我坚持使用 FoxPro 和这个特定的架构。但是，我可以自由地改变解决问题的方法。当然，我可以自己写DB访问代码，但是如果能用EF就更好了。
发送到 VFP 的查询实际上看起来像这样：
SELECT
E1.Wn_Ref,
E1.Wn_Surname,
E1.Wn_Forenam,
E1.Wn_Dirctr,
...
E1.Wn_Chqno,
CAST( E1.Wn_Lelval AS n(20,2)) AS Wn_Lelval,
E1.Wn_Dirstpd,
...
E1.Wn_Leavdt,
CAST( E1.Wn_Grsprv AS n(20,2)) AS Wn_Grsprv,
CAST( E1.Wn_Taxprv AS n(20,2)) AS Wn_Taxprv,
E1.Wn_Ovride,
E1.Wn_Nichgpr,
...
E1.Wn_Totabs,
CAST( E1.Wn_Tgrspay AS n(20,2)) AS Wn_Tgrspay,
CAST( E1.Wn_Tottax AS n(20,2)) AS Wn_Tottax,
CAST( E1.Wn_Totpens AS n(20,2)) AS Wn_Totpens,
CAST( E1.Wn_Totsspr AS n(20,2)) AS Wn_Totsspr,
CAST( E1.Wn_Totsmp AS n(20,2)) AS Wn_Totsmp,
CAST( E1.Wn_Totchrt AS n(20,2)) AS Wn_Totchrt,
CAST( E1.Wn_Totcmee AS n(20,2)) AS Wn_Totcmee,
CAST( E1.Wn_Totcmer AS n(20,2)) AS Wn_Totcmer,
CAST( E1.Wn_Tcmeeyr AS n(20,2)) AS Wn_Tcmeeyr,
CAST( E1.Wn_Tcmeryr AS n(20,2)) AS Wn_Tcmeryr,
CAST( E1.Wn_Totpenl AS n(20,2)) AS Wn_Totpenl,
CAST( E1.Wn_Totpay AS n(20,2)) AS Wn_Totpay,
CAST( E1.Wn_Tothol AS n(20,1)) AS Wn_Tothol,
CAST( E1.Wn_Roundbf AS n(20,2)) AS Wn_Roundbf,
E1.Wl_Totsspd,
E1.Wl_Totabs,
CAST( E1.Wl_Tgrspay AS n(20,2)) AS Wl_Tgrspay,
CAST( E1.Wl_Tottax AS n(20,2)) AS Wl_Tottax,
CAST( E1.Wl_Totpens AS n(20,2)) AS Wl_Totpens,
CAST( E1.Wl_Totsspr AS n(20,2)) AS Wl_Totsspr,
CAST( E1.Wl_Totsmp AS n(20,2)) AS Wl_Totsmp,
CAST( E1.Wl_Totchrt AS n(20,2)) AS Wl_Totchrt,
CAST( E1.Wl_Totcmee AS n(20,2)) AS Wl_Totcmee,
CAST( E1.Wl_Totcmer AS n(20,2)) AS Wl_Totcmer,
CAST( E1.Wl_Tcmeeyr AS n(20,2)) AS Wl_Tcmeeyr,
CAST( E1.Wl_Tcmeryr AS n(20,2)) AS Wl_Tcmeryr,
CAST( E1.Wl_Totpenl AS n(20,2)) AS Wl_Totpenl,
CAST( E1.Wl_Totpay AS n(20,2)) AS Wl_Totpay,
CAST( E1.Wl_Tothol AS n(20,1)) AS Wl_Tothol,
CAST( E1.Wl_Txb AS n(20,2)) AS Wl_Txb,
CAST( E1.Wl_Tax AS n(20,2)) AS Wl_Tax,
CAST( E1.Wl_Net AS n(20,2)) AS Wl_Net,
CAST( E1.Wl_Erni AS n(20,2)) AS Wl_Erni,
CAST( E1.Wl_Eeni AS n(20,2)) AS Wl_Eeni,
CAST( E1.Wl_Cnoni AS n(20,2)) AS Wl_Cnoni,
CAST( E1.Wl_Nien AS n(20,2)) AS Wl_Nien,
CAST( E1.Wl_Nieco AS n(20,2)) AS Wl_Nieco,
CAST( E1.Wl_Compee AS n(20,2)) AS Wl_Compee,
CAST( E1.Wl_Comper AS n(20,2)) AS Wl_Comper,
CAST( E1.Wl_Pen AS n(20,2)) AS Wl_Pen,
CAST( E1.Wl_Penbl AS n(20,2)) AS Wl_Penbl,
CAST( E1.Wl_Roundcf AS n(20,2)) AS Wl_Roundcf,
CAST( E1.Wn_Ssp1 AS n(20,2)) AS Wn_Ssp1,
CAST( E1.Wn_Ssp2 AS n(20,2)) AS Wn_Ssp2,
CAST( E1.Wn_Ssp3 AS n(20,2)) AS Wn_Ssp3,
CAST( E1.Wn_Ssp4 AS n(20,2)) AS Wn_Ssp4,
CAST( E1.Wn_Ssp5 AS n(20,2)) AS Wn_Ssp5,
CAST( E1.Wn_Ssp6 AS n(20,2)) AS Wn_Ssp6,
CAST( E1.Wn_Ssp7 AS n(20,2)) AS Wn_Ssp7,
CAST( E1.Wn_Ssp8 AS n(20,2)) AS Wn_Ssp8,
E1.Wn_Ssprate,
...
E1.Wn_Pwxretn
FROM (SELECT
Wname.Wn_Ref,
...
Wname.Wn_Chqno,
CAST( Wname.Wn_Lelval AS n(20,2)) AS Wn_Lelval,
Wname.Wn_Dirstpd,
Wname.Wn_Payfrq,
Wname.Wn_Birth,
Wname.Wn_Startdt,
Wname.Wn_Leavdt,
CAST( Wname.Wn_Grsprv AS n(20,2)) AS Wn_Grsprv,
CAST( Wname.Wn_Taxprv AS n(20,2)) AS Wn_Taxprv,
Wname.Wn_Ovride,
...
Wname.Wn_Totabs,
CAST( Wname.Wn_Tgrspay AS n(20,2)) AS Wn_Tgrspay,
CAST( Wname.Wn_Tottax AS n(20,2)) AS Wn_Tottax,
CAST( Wname.Wn_Totpens AS n(20,2)) AS Wn_Totpens,
CAST( Wname.Wn_Totsspr AS n(20,2)) AS Wn_Totsspr,
CAST( Wname.Wn_Totsmp AS n(20,2)) AS Wn_Totsmp,
CAST( Wname.Wn_Totchrt AS n(20,2)) AS Wn_Totchrt,
CAST( Wname.Wn_Totcmee AS n(20,2)) AS Wn_Totcmee,
CAST( Wname.Wn_Totcmer AS n(20,2)) AS Wn_Totcmer,
CAST( Wname.Wn_Tcmeeyr AS n(20,2)) AS Wn_Tcmeeyr,
CAST( Wname.Wn_Tcmeryr AS n(20,2)) AS Wn_Tcmeryr,
CAST( Wname.Wn_Totpenl AS n(20,2)) AS Wn_Totpenl,
CAST( Wname.Wn_Totpay AS n(20,2)) AS Wn_Totpay,
CAST( Wname.Wn_Tothol AS n(20,1)) AS Wn_Tothol,
CAST( Wname.Wn_Roundbf AS n(20,2)) AS Wn_Roundbf,
Wname.Wl_Totsspd,
Wname.Wl_Totabs,
CAST( Wname.Wl_Tgrspay AS n(20,2)) AS Wl_Tgrspay,
CAST( Wname.Wl_Tottax AS n(20,2)) AS Wl_Tottax,
CAST( Wname.Wl_Totpens AS n(20,2)) AS Wl_Totpens,
CAST( Wname.Wl_Totsspr AS n(20,2)) AS Wl_Totsspr,
CAST( Wname.Wl_Totsmp AS n(20,2)) AS Wl_Totsmp,
CAST( Wname.Wl_Totchrt AS n(20,2)) AS Wl_Totchrt,
CAST( Wname.Wl_Totcmee AS n(20,2)) AS Wl_Totcmee,
CAST( Wname.Wl_Totcmer AS n(20,2)) AS Wl_Totcmer,
CAST( Wname.Wl_Tcmeeyr AS n(20,2)) AS Wl_Tcmeeyr,
CAST( Wname.Wl_Tcmeryr AS n(20,2)) AS Wl_Tcmeryr,
CAST( Wname.Wl_Totpenl AS n(20,2)) AS Wl_Totpenl,
CAST( Wname.Wl_Totpay AS n(20,2)) AS Wl_Totpay,
CAST( Wname.Wl_Tothol AS n(20,1)) AS Wl_Tothol,
CAST( Wname.Wl_Txb AS n(20,2)) AS Wl_Txb,
CAST( Wname.Wl_Tax AS n(20,2)) AS Wl_Tax,
CAST( Wname.Wl_Net AS n(20,2)) AS Wl_Net,
CAST( Wname.Wl_Erni AS n(20,2)) AS Wl_Erni,
CAST( Wname.Wl_Eeni AS n(20,2)) AS Wl_Eeni,
CAST( Wname.Wl_Cnoni AS n(20,2)) AS Wl_Cnoni,
CAST( Wname.Wl_Nien AS n(20,2)) AS Wl_Nien,
CAST( Wname.Wl_Nieco AS n(20,2)) AS Wl_Nieco,
CAST( Wname.Wl_Compee AS n(20,2)) AS Wl_Compee,
CAST( Wname.Wl_Comper AS n(20,2)) AS Wl_Comper,
CAST( Wname.Wl_Pen AS n(20,2)) AS Wl_Pen,
CAST( Wname.Wl_Penbl AS n(20,2)) AS Wl_Penbl,
CAST( Wname.Wl_Roundcf AS n(20,2)) AS Wl_Roundcf,
CAST( Wname.Wn_Ssp1 AS n(20,2)) AS Wn_Ssp1,
CAST( Wname.Wn_Ssp2 AS n(20,2)) AS Wn_Ssp2,
CAST( Wname.Wn_Ssp3 AS n(20,2)) AS Wn_Ssp3,
CAST( Wname.Wn_Ssp4 AS n(20,2)) AS Wn_Ssp4,
CAST( Wname.Wn_Ssp5 AS n(20,2)) AS Wn_Ssp5,
CAST( Wname.Wn_Ssp6 AS n(20,2)) AS Wn_Ssp6,
CAST( Wname.Wn_Ssp7 AS n(20,2)) AS Wn_Ssp7,
CAST( Wname.Wn_Ssp8 AS n(20,2)) AS Wn_Ssp8,
Wname.Wn_Ssprate,
...
FROM Wname Wname) E1
虽然您可能无法选择数据库，但您可以选择 Entity Framework 吗？我发现使用 Dapper 更适合这种情况，并且可以让您对查询进行低级控制。
sql 语句可能超过 8000+ 限制的原因有很多。作为 VFP EF Provider 的作者，鉴于 VFP 和 Entity Framework 之间的各种限制，我已经尝试尽可能减少 sql 语句。但是 240 个字段没有太多回旋余地。就我个人而言，我会接受 Cetin Basoz 的建议，即通过创建多个 类 来将其视为多个 table，这些 类 代表 table 到 trim 的一部分 sql 语句。或者，您可以使用 LINQ Select 操作只提供字段的子集。那应该为您减少语句，使其不超过 8000+ 限制。
（取消对你的 linq 语句的假设，因为它没有显示......）
如果您确实需要所有列，那么您可能想尝试在仅获取主键的查询和使用主键 return 所有字段的查询之间分解查询。这可能对你有用。
我自己的回答：在处理了一段时间后，我发现 tables 以只读方式添加到 EDMX 模型中。这意味着它是 selecting 来自 select 语句，这是多余的，并且膨胀了 select 语句的大小。当我手动编辑 EDMX 文件并强制其将 table 视为可读写时，问题消失了。
此外，在 Tom 的建议下，我开始更好地欣赏代码优先方法。我完全取消了 EDMX 模型。我发现这更容易管理，因为我通过模型的 class 属性上的属性控制每个字段的处理方式。使用代码优先，我对上下文 classes 的自定义不可能被覆盖；这对我来说是完美的，因为我需要自定义构造函数并覆盖 SaveChanges 和其他方法。
我正在尝试将 Entity Framework 6 (EF) 与 Visual FoxPro 数据库一起使用（使用来自 NuGet 的包 VFPEntityFrameworkProvider2），我能够很好地建立连接。我能够从大多数表中加载数据。
当我尝试检索具有大约 240 个字段的特定类型的 DbSet 时出现问题。抛出的异常包含消息：
Compiled code for this line is too long.
据我所知，EF 编写了 SQL select 语句来检索数据，并且此语句太长。当我使用调试器检查局部变量时，我看到一个 SQL 语句，其长度接近 16000 个字符，而 maximum allowed command length for VFP is 8,192 bytes
我不太确定如何解决这个问题，因为我对 EF 还很陌生。我想我可以编辑一些生成的代码，或者编写一些自定义处理程序。也许我可以批量检索字段，然后组合对象。
此外，我相信可以将我的实体分解为类型和子类型；也许如果我这样做，一次只会检索一部分字段。
谁能建议我用什么方式解决这个限制？
添加的注释：
不能选择使用不同的数据库。我坚持使用 FoxPro 和这个特定的架构。但是，我可以自由地改变解决问题的方法。当然，我可以自己写DB访问代码，但是如果能用EF就更好了。
发送到 VFP 的查询实际上看起来像这样：
SELECT
E1.Wn_Ref,
E1.Wn_Surname,
E1.Wn_Forenam,
E1.Wn_Dirctr,
...
E1.Wn_Chqno,
CAST( E1.Wn_Lelval AS n(20,2)) AS Wn_Lelval,
E1.Wn_Dirstpd,
...
E1.Wn_Leavdt,
CAST( E1.Wn_Grsprv AS n(20,2)) AS Wn_Grsprv,
CAST( E1.Wn_Taxprv AS n(20,2)) AS Wn_Taxprv,
E1.Wn_Ovride,
E1.Wn_Nichgpr,
...
E1.Wn_Totabs,
CAST( E1.Wn_Tgrspay AS n(20,2)) AS Wn_Tgrspay,
CAST( E1.Wn_Tottax AS n(20,2)) AS Wn_Tottax,
CAST( E1.Wn_Totpens AS n(20,2)) AS Wn_Totpens,
CAST( E1.Wn_Totsspr AS n(20,2)) AS Wn_Totsspr,
CAST( E1.Wn_Totsmp AS n(20,2)) AS Wn_Totsmp,
CAST( E1.Wn_Totchrt AS n(20,2)) AS Wn_Totchrt,
CAST( E1.Wn_Totcmee AS n(20,2)) AS Wn_Totcmee,
CAST( E1.Wn_Totcmer AS n(20,2)) AS Wn_Totcmer,
CAST( E1.Wn_Tcmeeyr AS n(20,2)) AS Wn_Tcmeeyr,
CAST( E1.Wn_Tcmeryr AS n(20,2)) AS Wn_Tcmeryr,
CAST( E1.Wn_Totpenl AS n(20,2)) AS Wn_Totpenl,
CAST( E1.Wn_Totpay AS n(20,2)) AS Wn_Totpay,
CAST( E1.Wn_Tothol AS n(20,1)) AS Wn_Tothol,
CAST( E1.Wn_Roundbf AS n(20,2)) AS Wn_Roundbf,
E1.Wl_Totsspd,
E1.Wl_Totabs,
CAST( E1.Wl_Tgrspay AS n(20,2)) AS Wl_Tgrspay,
CAST( E1.Wl_Tottax AS n(20,2)) AS Wl_Tottax,
CAST( E1.Wl_Totpens AS n(20,2)) AS Wl_Totpens,
CAST( E1.Wl_Totsspr AS n(20,2)) AS Wl_Totsspr,
CAST( E1.Wl_Totsmp AS n(20,2)) AS Wl_Totsmp,
CAST( E1.Wl_Totchrt AS n(20,2)) AS Wl_Totchrt,
CAST( E1.Wl_Totcmee AS n(20,2)) AS Wl_Totcmee,
CAST( E1.Wl_Totcmer AS n(20,2)) AS Wl_Totcmer,
CAST( E1.Wl_Tcmeeyr AS n(20,2)) AS Wl_Tcmeeyr,
CAST( E1.Wl_Tcmeryr AS n(20,2)) AS Wl_Tcmeryr,
CAST( E1.Wl_Totpenl AS n(20,2)) AS Wl_Totpenl,
CAST( E1.Wl_Totpay AS n(20,2)) AS Wl_Totpay,
CAST( E1.Wl_Tothol AS n(20,1)) AS Wl_Tothol,
CAST( E1.Wl_Txb AS n(20,2)) AS Wl_Txb,
CAST( E1.Wl_Tax AS n(20,2)) AS Wl_Tax,
CAST( E1.Wl_Net AS n(20,2)) AS Wl_Net,
CAST( E1.Wl_Erni AS n(20,2)) AS Wl_Erni,
CAST( E1.Wl_Eeni AS n(20,2)) AS Wl_Eeni,
CAST( E1.Wl_Cnoni AS n(20,2)) AS Wl_Cnoni,
CAST( E1.Wl_Nien AS n(20,2)) AS Wl_Nien,
CAST( E1.Wl_Nieco AS n(20,2)) AS Wl_Nieco,
CAST( E1.Wl_Compee AS n(20,2)) AS Wl_Compee,
CAST( E1.Wl_Comper AS n(20,2)) AS Wl_Comper,
CAST( E1.Wl_Pen AS n(20,2)) AS Wl_Pen,
CAST( E1.Wl_Penbl AS n(20,2)) AS Wl_Penbl,
CAST( E1.Wl_Roundcf AS n(20,2)) AS Wl_Roundcf,
CAST( E1.Wn_Ssp1 AS n(20,2)) AS Wn_Ssp1,
CAST( E1.Wn_Ssp2 AS n(20,2)) AS Wn_Ssp2,
CAST( E1.Wn_Ssp3 AS n(20,2)) AS Wn_Ssp3,
CAST( E1.Wn_Ssp4 AS n(20,2)) AS Wn_Ssp4,
CAST( E1.Wn_Ssp5 AS n(20,2)) AS Wn_Ssp5,
CAST( E1.Wn_Ssp6 AS n(20,2)) AS Wn_Ssp6,
CAST( E1.Wn_Ssp7 AS n(20,2)) AS Wn_Ssp7,
CAST( E1.Wn_Ssp8 AS n(20,2)) AS Wn_Ssp8,
E1.Wn_Ssprate,
...
E1.Wn_Pwxretn
FROM (SELECT
Wname.Wn_Ref,
...
Wname.Wn_Chqno,
CAST( Wname.Wn_Lelval AS n(20,2)) AS Wn_Lelval,
Wname.Wn_Dirstpd,
Wname.Wn_Payfrq,
Wname.Wn_Birth,
Wname.Wn_Startdt,
Wname.Wn_Leavdt,
CAST( Wname.Wn_Grsprv AS n(20,2)) AS Wn_Grsprv,
CAST( Wname.Wn_Taxprv AS n(20,2)) AS Wn_Taxprv,
Wname.Wn_Ovride,
...
Wname.Wn_Totabs,
CAST( Wname.Wn_Tgrspay AS n(20,2)) AS Wn_Tgrspay,
CAST( Wname.Wn_Tottax AS n(20,2)) AS Wn_Tottax,
CAST( Wname.Wn_Totpens AS n(20,2)) AS Wn_Totpens,
CAST( Wname.Wn_Totsspr AS n(20,2)) AS Wn_Totsspr,
CAST( Wname.Wn_Totsmp AS n(20,2)) AS Wn_Totsmp,
CAST( Wname.Wn_Totchrt AS n(20,2)) AS Wn_Totchrt,
CAST( Wname.Wn_Totcmee AS n(20,2)) AS Wn_Totcmee,
CAST( Wname.Wn_Totcmer AS n(20,2)) AS Wn_Totcmer,
CAST( Wname.Wn_Tcmeeyr AS n(20,2)) AS Wn_Tcmeeyr,
CAST( Wname.Wn_Tcmeryr AS n(20,2)) AS Wn_Tcmeryr,
CAST( Wname.Wn_Totpenl AS n(20,2)) AS Wn_Totpenl,
CAST( Wname.Wn_Totpay AS n(20,2)) AS Wn_Totpay,
CAST( Wname.Wn_Tothol AS n(20,1)) AS Wn_Tothol,
CAST( Wname.Wn_Roundbf AS n(20,2)) AS Wn_Roundbf,
Wname.Wl_Totsspd,
Wname.Wl_Totabs,
CAST( Wname.Wl_Tgrspay AS n(20,2)) AS Wl_Tgrspay,
CAST( Wname.Wl_Tottax AS n(20,2)) AS Wl_Tottax,
CAST( Wname.Wl_Totpens AS n(20,2)) AS Wl_Totpens,
CAST( Wname.Wl_Totsspr AS n(20,2)) AS Wl_Totsspr,
CAST( Wname.Wl_Totsmp AS n(20,2)) AS Wl_Totsmp,
CAST( Wname.Wl_Totchrt AS n(20,2)) AS Wl_Totchrt,
CAST( Wname.Wl_Totcmee AS n(20,2)) AS Wl_Totcmee,
CAST( Wname.Wl_Totcmer AS n(20,2)) AS Wl_Totcmer,
CAST( Wname.Wl_Tcmeeyr AS n(20,2)) AS Wl_Tcmeeyr,
CAST( Wname.Wl_Tcmeryr AS n(20,2)) AS Wl_Tcmeryr,
CAST( Wname.Wl_Totpenl AS n(20,2)) AS Wl_Totpenl,
CAST( Wname.Wl_Totpay AS n(20,2)) AS Wl_Totpay,
CAST( Wname.Wl_Tothol AS n(20,1)) AS Wl_Tothol,
CAST( Wname.Wl_Txb AS n(20,2)) AS Wl_Txb,
CAST( Wname.Wl_Tax AS n(20,2)) AS Wl_Tax,
CAST( Wname.Wl_Net AS n(20,2)) AS Wl_Net,
CAST( Wname.Wl_Erni AS n(20,2)) AS Wl_Erni,
CAST( Wname.Wl_Eeni AS n(20,2)) AS Wl_Eeni,
CAST( Wname.Wl_Cnoni AS n(20,2)) AS Wl_Cnoni,
CAST( Wname.Wl_Nien AS n(20,2)) AS Wl_Nien,
CAST( Wname.Wl_Nieco AS n(20,2)) AS Wl_Nieco,
CAST( Wname.Wl_Compee AS n(20,2)) AS Wl_Compee,
CAST( Wname.Wl_Comper AS n(20,2)) AS Wl_Comper,
CAST( Wname.Wl_Pen AS n(20,2)) AS Wl_Pen,
CAST( Wname.Wl_Penbl AS n(20,2)) AS Wl_Penbl,
CAST( Wname.Wl_Roundcf AS n(20,2)) AS Wl_Roundcf,
CAST( Wname.Wn_Ssp1 AS n(20,2)) AS Wn_Ssp1,
CAST( Wname.Wn_Ssp2 AS n(20,2)) AS Wn_Ssp2,
CAST( Wname.Wn_Ssp3 AS n(20,2)) AS Wn_Ssp3,
CAST( Wname.Wn_Ssp4 AS n(20,2)) AS Wn_Ssp4,
CAST( Wname.Wn_Ssp5 AS n(20,2)) AS Wn_Ssp5,
CAST( Wname.Wn_Ssp6 AS n(20,2)) AS Wn_Ssp6,
CAST( Wname.Wn_Ssp7 AS n(20,2)) AS Wn_Ssp7,
CAST( Wname.Wn_Ssp8 AS n(20,2)) AS Wn_Ssp8,
Wname.Wn_Ssprate,
...
FROM Wname Wname) E1
虽然您可能无法选择数据库，但您可以选择 Entity Framework 吗？我发现使用 Dapper 更适合这种情况，并且可以让您对查询进行低级控制。
sql 语句可能超过 8000+ 限制的原因有很多。作为 VFP EF Provider 的作者，鉴于 VFP 和 Entity Framework 之间的各种限制，我已经尝试尽可能减少 sql 语句。但是 240 个字段没有太多回旋余地。就我个人而言，我会接受 Cetin Basoz 的建议，即通过创建多个 类 来将其视为多个 table，这些 类 代表 table 到 trim 的一部分 sql 语句。或者，您可以使用 LINQ Select 操作只提供字段的子集。那应该为您减少语句，使其不超过 8000+ 限制。
（取消对你的 linq 语句的假设，因为它没有显示......） 如果您确实需要所有列，那么您可能想尝试在仅获取主键的查询和使用主键 return 所有字段的查询之间分解查询。这可能对你有用。
我自己的回答：在处理了一段时间后，我发现 tables 以只读方式添加到 EDMX 模型中。这意味着它是 selecting 来自 select 语句，这是多余的，并且膨胀了 select 语句的大小。当我手动编辑 EDMX 文件并强制其将 table 视为可读写时，问题消失了。
此外，在 Tom 的建议下，我开始更好地欣赏代码优先方法。我完全取消了 EDMX 模型。我发现这更容易管理，因为我通过模型的 class 属性上的属性控制每个字段的处理方式。使用代码优先，我对上下文 classes 的自定义不可能被覆盖；这对我来说是完美的，因为我需要自定义构造函数并覆盖 SaveChanges 和其他方法。