Oracle数据库中LONG类型字段的存取

Oracle中存取4000字节以上大文本类型可以用此数据类型，其在C#中的读写方法如下： 注重需要引用：System.Data.OracleClient 然后添加命名空间：using System.Data.OracleClient Oracle建库脚本： CREATE TABLE TEST (AGREEMENT_ID CHAR(3) NOT NULL,AGREEMENT_CONTENT LONGNULL ) 插入数据： protected void Button1_Click(object sender, EventArgs e){OracleConnection conn = new OracleConnection(@'PassWord=XXXXXX;User ID=hk;Data Source=wealth;Persist Security Info=True');conn.Open();OracleCommand cmd = new OracleCommand('Select * From TEST', conn);string sql = 'Insert Into TEST (AGREEMENT_ID, AGREEMENT_CONTENT) Values(:P_ID, :P_Value)';cmd.CommandText = sql;cmd.Parameters.Add('P_ID', this.TextBox2.Text);cmd.Parameters.Add('P_Value', this.TextBox1.Text);cmd.ExecuteNonQuery();conn.Close(); } 读取数据： protected void Button2_Click(object sender, EventArgs e){OracleConnection conn = new OracleConnection(@'Password=XXXXXX;User ID=hk;Data Source=wealth;Persist Security Info=True');conn.Open();string sql = 'Select * From TEST where AGREEMENT_ID = :P_ID';OracleDataAdapter da = new OracleDataAdapter(sql, conn);da.SelectCommand.Parameters.Add('P_ID', this.TextBox2.Text);DataSet ds = new DataSet();da.Fill(ds);this.TextBox1.Text = ds.Tables[0].Rows.Count.ToString();this.TextBox1.Text = ds.Tables[0].Rows[0]['AGREEMENT_CONTENT'].ToString();conn.Close(); }