如何检查Access数据库表中是否存在特定列 [英] How to check if specific column exists in an Access database table

问题描述

我想知道如何检查Access数据库中特定表(例如myTable)中是否存在特定列(例如日期).

I want to know how to check if a specific column (e.g: date) exists in a specific table(e.g: myTable) in an Access database.

我已阅读此答案提供一个查询，该查询导致另一个查询.

I've read this answer which offers a query which results in another query.

IF NOT EXISTS(SELECT * 
              FROM sys.columns 
              WHERE [name] = N'columnName' 
                AND [object_id] = OBJECT_ID(N'tableName'))
BEGIN
    ALTER TABLE ADD COLUMN MYCOLUMN
END

但是我需要的是true/false结果.

更新1

如何在C#应用程序中做到这一点?

How can I do that in my C# application?

也许使用SqlCommand.ExecuteScalar()或其他方式?

推荐答案

感谢提供解决方案的每个人，收集了一些答案，我提出了自己的解决方案版本.也许这不是最好的解决方案，但是至少我不需要额外的dll来添加引用或处理某些不支持Access的stored procedures.

Thanks to everyone who offered a solution, gathering up some of the answers, I came up with my own version of solution. Maybe it's not the best solution around, but at least I don't need an extra dll to add to the references or deal with some stored procedures Access won't support.

OleDbConnection con = new OleDbConnection("my database address");
OleDbCommand cmd = new OleDbCommand();
cmd.Connection = con;
cmd.CommandType = CommandType.Text;
cmd.CommandText = "SELECT TOP 1 date FROM myTable";
con.Open();
bool exists = true;
try
{
  var x = cmd.ExecuteScalar();
}
catch (Exception e)
{
  exists = false;
}
con.Close();

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