如何使用精致小巧的强类型的查询参数与Sybase ASE？

问题描述

小巧玲珑可以通过查询参数匿名对象，支持任何ADO.NET数据提供程序。然而，反对的Sybase 15 ADO.NET驱动程序运行下面的查询时：

Dapper can pass query parameters as anonymous objects, and supports any ADO.NET data provider. However, when running the following query against the Sybase 15 ADO.NET drivers:

using (var connection = new AseConnection("..."))
{
    connection.Open();

    var results = connection.Query<Foo>(
        "dbo.sp_columns", new { table_name = "dbo.sysusers"}, 
        commandType: CommandType.StoredProcedure);
}

...以下错误被抛出：

... the following error is thrown:

Sybase.Data.AseClient.AseException: Procedure sp_columns expects parameter @table_name, which was not supplied.

at Sybase.Data.AseClient.AseCommand.ᜁ(Int32 A_0)
at Sybase.Data.AseClient.AseCommand.ᜄ()
at Sybase.Data.AseClient.AseCommand.ᜀ(CommandBehavior A_0)
at Sybase.Data.AseClient.AseCommand.System.Data.IDbCommand.ExecuteReader()
at Dapper.SqlMapper.<QueryInternal>d__13`1.MoveNext() in SqlMapper.cs: line 579
at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
at System.Linq.Enumerable.ToList(IEnumerable`1 source)
at Dapper.SqlMapper.Query(IDbConnection cnn, String sql, Object param, IDbTransaction transaction, Boolean buffered, Nullable`1 commandTimeout, Nullable`1 commandType) in SqlMapper.cs: line 536

更改到一个小巧玲珑的 DynamicParameters 设置@table_name也不起作用。

Changing it to a Dapper DynamicParameters set with "@table_name" also doesn't work.

我怎样才能通强类型参数的Sybase与精致小巧的？

How can I pass strongly-typed parameters to Sybase with Dapper?

推荐答案

据我所知道的，原因似乎是是与Sybase的 AseParameter 类，不正确映射的DbType 到 AseDbType 值。

As far as I can tell, the reason seems to be something to do with Sybase's AseParameter class, and not correctly mapping DbType to AseDbType values.

您可以解决的问题，通过定义自定义小巧玲珑 IDynamicParameters 设置，并与 AseParameter 填充它直接对象

You can work around the problem by defining a custom Dapper IDynamicParameters set, and populating it with AseParameter objects directly:

public class AseCommandParameters : List<AseParameter>, SqlMapper.IDynamicParameters
{
    public void AddParameters(IDbCommand command, SqlMapper.Identity identity)
    {
        foreach (var parameter in this)
            command.Parameters.Add(parameter);
    }
}

然后通过一个实例到查询：

And then passing an instance into the query:

using (var connection = new AseConnection("..."))
{
    connection.Open();

    var parameters = new AseCommandParameters
    {
        new AseParameter("@table_name", "dbo.sysusers")
    };

    var results = connection.Query<Foo>("dbo.sp_columns", parameters, 
        commandType: CommandType.StoredProcedure);
}

这工作，也可以指定 AseDbType 每个参数。

This works, and also lets you specify the AseDbType for each parameter.

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