SQL: 
declare v_cnt Number; 
    begin 
        select count(1) into v_cnt from user_tables where table_name = 'BITS_UPGRADE_LOG'; 
        if v_cnt = 0 then 
             execute immediate 'create table BITS_UPGRADE_LOG
                              (
                                UPGRADEDATE DATE,
                                VERSION     VARCHAR2(1000)
                              ) ';  
        end If; 
        insert into bits_upgrade_log
                  (upgradedate, version)
                values
                  (sysdate, '1');
     End;C#代码: 
 
string ConnectionString = string.Format("Data Source={0};User Id ={1};Password = {2};", 
                                                            tbDataBase.Text, tbUserName.Text, tbPassWord.Text);//写连接串
                OracleConnection conn = new OracleConnection(ConnectionString);
                OracleCommand comm = new OracleCommand();
                string strSql =string.Format(@"declare v_cnt Number; 
                                                begin  select count(1) into v_cnt from user_tables where table_name = 'BITS_UPGRADE_LOG'; 
                                                    if v_cnt = 0 then 
                                                         execute immediate 'create table BITS_UPGRADE_LOG
                                                                          (
                                                                            UPGRADEDATE DATE,
                                                                            VERSION     VARCHAR2(1000)
                                                                          ) ';  
                                                    end If; 
                                                    insert into bits_upgrade_log
                                                              (upgradedate, version)
                                                            values
                                                              (sysdate, '{0}');
                                                 End; ",label9.Text)  ;                comm.CommandText = strSql;
                comm.Connection = conn;
                conn.Open();
                comm.ExecuteNonQuery();
                conn.Close();