读取oracle blob字符串
OleDbConnectioncon=newOleDbConnection(cnnstr);
try
{
con.Open();
}
catch
{}
OleDbCommandcmd=newOleDbCommand(strSQL,con);
System.Data.OleDb.OleDbDataReaderdr=cmd.ExecuteReader();
while(dr.Read())
{
stringdd=dr["gggg"].ToString();
byte[]ooo=(byte[])dr["hhhh"];
stringstr;
str=System.Text.Encoding.Unicode.GetString(ooo);
this.textBox1.Text=str;
}
}
//向数据库中写入
private void button1_Click(object sender, EventArgs e)
{
oracleConnection1.Open();
OracleCommand cmd = new OracleCommand("UPDATE TEST SET F2 =:blob where F1=:sn ", oracleConnection1);
cmd.Parameters.Add(new OracleParameter("blob",OracleType.Blob));
cmd.Parameters.Add(new OracleParameter("sn",OracleType.Int32));
FileInfo fi = new FileInfo("c:\\dos.doc");
FileStream fs = fi.OpenRead();
byte[] MyData = new byte[fs.Length];
fs.Read(MyData, 0, System.Convert.ToInt32(fs.Length));
fs.Close();
cmd.Parameters["blob"].Value = MyData;
cmd.Parameters["sn"].Value = 1;
&nbs
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q 触发器是当特定事件出现时自动执行的存储过程
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q 触发器的功能：
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