首页 > 解决方案 > 错误“结果空间不足,无法将 uniqueidentifier 值转换为 char。”

问题描述

插件表:

CREATE TABLE [dbo].[CcureMessage] 
(
      [CcureMessageId] [UNIQUEIDENTIFIER] NOT NULL,
      [Event] [VARCHAR](20) NULL,
      [Type] [VARCHAR](20) NULL,
      [Message] [VARCHAR](MAX) NOT NULL,
      [Xml] [VARCHAR](4000) NOT NULL,

      CONSTRAINT [PK_CcureMessage] 
          PRIMARY KEY CLUSTERED ([CcureMessageId] ASC)
                      WITH (STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF)  ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
GO

ALTER TABLE [dbo].[CcureMessage] 
    ADD CONSTRAINT [DF_CcureMessage_CcureMessageId]  
        DEFAULT (NEWID()) FOR [CcureMessageId]
GO

我使 PK 表具有默认值,因此我根本没有传递 GUID,但似乎我仍然收到与 guid 相关的错误。

通过 SSMS 插入可以正常工作的命令:

INSERT INTO CcureMessage (Event, Type, Message, Xml) 
VALUES ('event 3', 'type 3', 'big json 3', 'xml-ish');

C#代码:

public void DoInsert(Message msg)
{
    // hard-coding this to set test values
    TopicMessage tm = new TopicMessage();
    tm.Event = "event 1";
    tm.Type = "Type 1";
    tm.Message = "json data message";
    tm.Xml = "xml data goes here";

    string connString = set to correct value;

    string sql = "INSERT INTO CcureMessage (Event, Type, Message, Xml) VALUES (@Event, @Type, @Message, @Xml)";

    using (SqlConnection conn = new SqlConnection(connString))
    {
        conn.Open();
        SqlCommand cmd = new SqlCommand(sql, conn);
        cmd.CommandType = System.Data.CommandType.Text;

        SqlParameter eventParm = new SqlParameter("@Event", tm.CcureMessageId);
        SqlParameter typeParm = new SqlParameter("@Type", tm.Type);
        SqlParameter msgParm = new SqlParameter("@Message", tm.Message);
        SqlParameter xmlParm = new SqlParameter("@Xml", tm.Xml);
        cmd.Parameters.Add(eventParm);
        cmd.Parameters.Add(typeParm);
        cmd.Parameters.Add(msgParm);
        cmd.Parameters.Add(xmlParm);

        cmd.ExecuteNonQuery();
    }
}

运行这会导致错误

结果空间不足,无法将 uniqueidentifier 值转换为 char

标签: c#sql-serveradoguiduniqueidentifier

解决方案


就我而言,我没有在 C# 代码中使用 guid 并收到此错误。所以追溯到存储过程,我发现错误直接来自那里。

我将其追溯到我在 GUID 字段上运行的转换,如下所示:

CONVERT(varchar(13), guid)

我认为它只会截断字段值。所以我不得不做以下事情:

CONVERT(varchar(13), CONVERT(varchar(36), guid))

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