.NET OracleLob 读写操作

本文内容

• OracleLob 操作 CLOB 字段
• OracleLob 操作 BLOB 字段

 

OracleLob 操作 CLOB 字段

向 Oracle Clob 字段写入数据

;

string id = string.Empty;

OracleConnection conn = new OracleConnection(connStr);

OracleCommand cmd = conn.CreateCommand();

// 字符串

id = Guid.NewGuid().ToString();

StringBuilder data = new StringBuilder();

for (int i = 1; i <= 100; i++) data.Append("a");

try

{

    conn.Open();

    //cmd.CommandText = "DROP TABLE mylobtable";

    //cmd.CommandType = CommandType.Text;

    //cmd.ExecuteNonQuery();

    //Response.Write("删除表'mylobtable'成功.<br />");

    cmd.CommandText = "CREATE TABLE mylobtable (a varchar2(36), b clob,c blob)";

    cmd.CommandType = CommandType.Text;

    cmd.ExecuteNonQuery();

    Response.Write("创建表 'mylobtable' 成功.<br />");

    // 一般方式

    cmd.CommandText = "INSERT INTO mylobtable(a,b) VALUES('" + id + "','" + data.ToString() + "')";

    cmd.CommandType = CommandType.Text;

    cmd.ExecuteNonQuery();

    Response.Write("添加成功.<br />");

    // 使用 OracleParameter OracleType.Clob

    cmd.CommandText = "INSERT INTO mylobtable(a,b) VALUES('" + id + "'," + ":data)";

    cmd.CommandType = CommandType.Text;

    cmd.Parameters.Clear();

    OracleParameter paraClob = new OracleParameter("data", OracleType.Clob);

    paraClob.Value = data.ToString();

    cmd.Parameters.Add(paraClob);

    cmd.ExecuteNonQuery();

    Response.Write("添加成功.<br />");

    // 使用 OracleParameter OracleType.NVarChar

    cmd.CommandText = "INSERT INTO mylobtable(a,b) VALUES('" + id + "'," + ":data)";

    cmd.CommandType = CommandType.Text;

    cmd.Parameters.Clear();

    OracleParameter paraNVarChar = new OracleParameter("data", OracleType.NVarChar);

    paraNVarChar.Value = data.ToString();

    cmd.Parameters.Add(paraNVarChar);

    cmd.ExecuteNonQuery();

    Response.Write("添加成功.<br />");

}

catch (Exception ex)

{

    Response.Write("失败." + ex);

}

finally

{

    cmd.Dispose();

    conn.Close();

    conn.Dispose();

}