OracleTypes
Oracle .NET Framework 数据提供程序包括多个可以用于使用 Oracle 数据类型的结构。 包括 OracleNumber 和 OracleString。
备注
有关此类结构的完整列表,请参见 System.Data.OracleClient。
创建 Oracle 表
此示例创建一个 Oracle 表并为该表加载数据。 必须先运行此示例,才能运行下一个示例。
public void Setup(string connectionString)
{
OracleConnection conn = new OracleConnection(connectionString);
try
{
conn.Open();
OracleCommand cmd = conn.CreateCommand();
cmd.CommandText ="CREATE TABLE OracleTypesTable " +
"(MyVarchar2 varchar2(3000),MyNumber number(28,4) " +
"PRIMARY KEY ,MyDate date, MyRaw raw(255))";
cmd.ExecuteNonQuery();
cmd.CommandText ="INSERT INTO OracleTypesTable VALUES " +
"( 'test', 2, to_date('2000-01-11 12:54:01','yyyy-mm-dd " +
"hh24:mi:ss'), '0001020304' )";
cmd.ExecuteNonQuery();
}
catch(Exception)
{
}
finally
{
conn.Close();
}
}
从 Oracle 表检索数据
此示例使用 OracleDataReader 访问数据,并使用多个 OracleType 结构显示数据。
public void ReadOracleTypesExample(string connectionString)
{
OracleConnection myConnection =
new OracleConnection(connectionString);
myConnection.Open();
OracleCommand myCommand = myConnection.CreateCommand();
try
{
myCommand.CommandText = "SELECT * from OracleTypesTable";
OracleDataReader oracledatareader1 = myCommand.ExecuteReader();
oracledatareader1.Read();
//Using the oracle specific getters for each type is faster than
//using GetOracleValue.
//First column, MyVarchar2, is a VARCHAR2 data type in Oracle
//Server and maps to OracleString.
OracleString oraclestring1 =
oracledatareader1.GetOracleString(0);
Console.WriteLine("OracleString " + oraclestring1.ToString());
//Second column, MyNumber, is a NUMBER data type in Oracle Server
//and maps to OracleNumber.
OracleNumber oraclenumber1 =
oracledatareader1.GetOracleNumber(1);
Console.WriteLine("OracleNumber " + oraclenumber1.ToString());
//Third column, MyDate, is a DATA data type in Oracle Server
//and maps to OracleDateTime.
OracleDateTime oracledatetime1 =
oracledatareader1.GetOracleDateTime(2);
Console.WriteLine("OracleDateTime " + oracledatetime1.ToString());
//Fourth column, MyRaw, is a RAW data type in Oracle Server and
//maps to OracleBinary.
OracleBinary oraclebinary1 =
oracledatareader1.GetOracleBinary(3);
//Calling value on a null OracleBinary throws
//OracleNullValueException; therefore, check for a null value.
if (oraclebinary1.IsNull==false)
{
foreach(byte b in oraclebinary1.Value)
{
Console.WriteLine("byte " + b.ToString());
}
}
oracledatareader1.Close();
}
catch(Exception e)
{
Console.WriteLine(e.ToString());
}
finally
{
myConnection.Close();
}
}