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浅谈PetShop之使用存储过程与PLSQL批量处理(附案例)

2013-03-03 20:32  夜雨瞳  阅读(1588)  评论(5)  编辑  收藏  举报

目录

1       大概思路... 2

2       PetShop4的经典数据库连接代码回顾... 3

2.1        PrepareCommand. 3

2.2        ExecuteNoQuery. 4

3       如何写好一个的OracleHelper 5

3.1        PetShop的OracleHelper 5

3.2        OracleHelper 6

4       代码示例... 6

4.1        使用存储过程... 6

4.2        批处理之使用PL/SQL. 7

4.3        批处理之使用事务... 8

5       运行效果... 10

6       小结... 10

 

1       大概思路

 

备注：黄色为影响参数

2       PetShop4的经典数据库连接代码回顾

PetShop4有3个函数，具体有：

ExecuteReader:可以读一个表的记录，只能读不能写。

ExecuteScalar:只能读一条记录，一般用来判断数据库是否有数据等，只能读不能写。

ExecuteNonQuery:可以写以可以读。

这里介绍一下PrepareCommand、ExecuteNoQuery。

2.1   PrepareCommand

注意：当前函数是private的，不提供给外部调用。

        /// <summary>
        /// Internal function to prepare a command for execution by the database
        /// </summary>
        /// <param name="cmd">Existing command object</param>
        /// <param name="conn">Database connection object</param>
        /// <param name="trans">Optional transaction object</param>
        /// <param name="cmdType">Command type, e.g. stored procedure</param>
        /// <param name="cmdText">Command test</param>
        /// <param name="commandParameters">Parameters for the command</param>
        private static void PrepareCommand(OracleCommand cmd, OracleConnection conn, OracleTransaction trans, CommandType cmdType, string cmdText, OracleParameter[] commandParameters) {
            //Open the connection if required
            if (conn.State != ConnectionState.Open)
                conn.Open();

            //Set up the command
            cmd.Connection = conn;
            cmd.CommandText = cmdText;
            cmd.CommandType = cmdType;

            //Bind it to the transaction if it exists
            if (trans != null)
                cmd.Transaction = trans;

            // Bind the parameters passed in
            if (commandParameters != null) {
                foreach (OracleParameter parm in commandParameters)
                    cmd.Parameters.Add(parm);
            }
        }

2.2   ExecuteNoQuery

此函数：传入连接串、执行类型、SQL、参数

       /// <summary>
        /// Execute a database query which does not include a select
        /// </summary>
        /// <param name="connString">Connection string to database</param>
        /// <param name="cmdType">Command type either stored procedure or SQL</param>
        /// <param name="cmdText">Acutall SQL Command</param>
        /// <param name="commandParameters">Parameters to bind to the command</param>
        /// <returns></returns>
        public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) {
            // Create a new Oracle command
            OracleCommand cmd = new OracleCommand();
            //Create a connection
            using (OracleConnection connection = new OracleConnection(connectionString)) {
                //Prepare the command
                PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
                //Execute the command
                int val = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
                return val;
            }
        }

此函数：传入事务、执行类型、SQL、参数

      /// <summary>
        /// Execute an OracleCommand (that returns no resultset) against an existing database transaction
        /// using the provided parameters.
        /// </summary>
        /// <remarks>
        /// e.g.: 
        ///  int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "PublishOrders", new OracleParameter(":prodid", 24));
        /// </remarks>
        /// <param name="trans">an existing database transaction</param>
        /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">the stored procedure name or PL/SQL command</param>
        /// <param name="commandParameters">an array of OracleParamters used to execute the command</param>
        /// <returns>an int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(OracleTransaction trans, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) {
            OracleCommand cmd = new OracleCommand();
            PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, commandParameters);
            int val = cmd.ExecuteNonQuery();
            cmd.Parameters.Clear();
            return val;
        }

 此函数：传入连接、执行类型、SQL、参数

       /// <summary>
        /// Execute an OracleCommand (that returns no resultset) against an existing database connection
        /// using the provided parameters.
        /// </summary>
        /// <remarks>
        /// e.g.: 
        ///  int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new OracleParameter(":prodid", 24));
        /// </remarks>
        /// <param name="conn">an existing database connection</param>
        /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">the stored procedure name or PL/SQL command</param>
        /// <param name="commandParameters">an array of OracleParamters used to execute the command</param>
        /// <returns>an int representing the number of rows affected by the command</returns>
        public static int ExecuteNonQuery(OracleConnection connection, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters) {
            OracleCommand cmd = new OracleCommand();
            PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
            int val = cmd.ExecuteNonQuery();
            cmd.Parameters.Clear();
            return val;
        }

3       如何写好一个的OracleHelper

3.1   PetShop的OracleHelper

PetShop不是写好了吗？为什么还要自己写？

eg:PetShop4的函数不足以方便我们操作数据库，如批量插入需要防注入的参数时，需要等全部插入完再提交整个事务。

eg:PetShop4的函数在处理存储过程里还不完善，返回值没有指向。

3.2   OracleHelper

注意：PetShop4在参数上在调用OracleHelper考虑了缓存，这里暂时不考虑。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using System.Data;
using System.Data.OracleClient;
using System.Collections;
namespace Util
{
    public abstract class OracleHelper
    {
        /// <summary>
        /// 准备存储过程执行查询
        /// </summary>        
        /// <param name="connectionString">数据库连接</param>
        public static OracleTransaction GetTrans(string connectionString)
        {
            OracleConnection conn = new OracleConnection(connectionString);
            conn.Open();
            OracleTransaction trans = conn.BeginTransaction();
            return trans;
        }

        /// <summary>
        /// 返回视图
        /// </summary>
        /// <param name="cmdType"></param>
        /// <param name="cmdText"></param>
        /// <param name="commandParameters"></param>
        /// <returns></returns>
        public static DataView ExecuteView(String connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters)
        {
            OracleCommand cmd = new OracleCommand();
            using (OracleConnection conn = new OracleConnection(connectionString))
            {
                PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
                DataSet ds = new DataSet();
                OracleDataAdapter da = new OracleDataAdapter(cmd);
                da.Fill(ds);
                DataView dv = ds.Tables[0].DefaultView;
                cmd.Parameters.Clear();
                return dv;
            }
        }
        /// <summary>
        /// 执行并返回影响行数
        /// </summary>
        /// <param name="connectionString">连接字符串</param>
        /// <param name="cmdType">执行类型</param>
        /// <param name="cmdText">执行文本</param>
        /// <param name="commandParameters">参数</param>
        /// <returns></returns>
        public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText, IList commandParameters)
        {
            OracleCommand cmd = new OracleCommand();
            using (OracleConnection connection = new OracleConnection(connectionString))
            {
                PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
                int val = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
                return val;
            }
        }

        /// <summary>
        /// Execute a database query which does not include a select
        /// </summary>
        /// <param name="connString">Connection string to database</param>
        /// <param name="cmdType">Command type either stored procedure or SQL</param>
        /// <param name="cmdText">Acutall SQL Command</param>
        /// <param name="commandParameters">Parameters to bind to the command</param>
        /// <returns></returns>
        public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters)
        {
            // Create a new Oracle command
            OracleCommand cmd = new OracleCommand();

            //Create a connection
            using (OracleConnection connection = new OracleConnection(connectionString))
            {

                //Prepare the command
                PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);

                //Execute the command
                int val = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
                return val;
            }
        }



        ///    <summary>
        ///    Execute    a OracleCommand (that returns a 1x1 resultset)    against    the    specified SqlTransaction
        ///    using the provided parameters.
        ///    </summary>
        ///    <param name="transaction">A    valid SqlTransaction</param>
        ///    <param name="commandType">The CommandType (stored procedure, text, etc.)</param>
        ///    <param name="commandText">The stored procedure name    or PL/SQL command</param>
        ///    <param name="commandParameters">An array of    OracleParamters used to execute the command</param>
        ///    <returns>An    object containing the value    in the 1x1 resultset generated by the command</returns>
        public static int ExecuteNonQuery(OracleTransaction trans, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters)
        {
            OracleCommand cmd = new OracleCommand();
            PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, commandParameters);
            int val = cmd.ExecuteNonQuery();
            cmd.Parameters.Clear();
            return val;
        }

        /// <summary>
        /// 执行并返回影响行数，得手动关闭数据库连接
        /// </summary>
        /// <param name="connection">连接字符串</param>
        /// <param name="cmdType">执行类型</param>
        /// <param name="cmdText">执行文本</param>
        /// <param name="commandParameters">参数</param>
        /// <returns></returns>
        public static int ExecuteNonQuery(OracleConnection connection, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters)
        {

            OracleCommand cmd = new OracleCommand();
            PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
            int val = cmd.ExecuteNonQuery();
            cmd.Parameters.Clear();
            return val;
        }

        /// <summary>
        /// Execute a select query that will return a result set
        /// </summary>
        /// <param name="connString">Connection string</param>
        //// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
        /// <param name="commandText">the stored procedure name or PL/SQL command</param>
        /// <param name="commandParameters">an array of OracleParamters used to execute the command</param>
        /// <returns></returns>
        public static OracleDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params OracleParameter[] commandParameters)
        {

            //Create the command and connection
            OracleCommand cmd = new OracleCommand();
            OracleConnection conn = new OracleConnection(connectionString);

            try
            {
                //Prepare the command to execute
                PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);

                //Execute the query, stating that the connection should close when the resulting datareader has been read
                OracleDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                cmd.Parameters.Clear();
                return rdr;

            }
            catch
            {

                //If an error occurs close the connection as the reader will not be used and we expect it to close the connection
                conn.Close();
                throw;
            }
        }


        /// <summary>
        /// Internal function to prepare a command for execution by the database
        /// </summary>
        /// <param name="cmd">Existing command object</param>
        /// <param name="conn">Database connection object</param>
        /// <param name="trans">Optional transaction object</param>
        /// <param name="cmdType">Command type, e.g. stored procedure</param>
        /// <param name="cmdText">Command test</param>
        /// <param name="commandParameters">Parameters for the command</param>
        private static void PrepareCommand(OracleCommand cmd, OracleConnection conn, OracleTransaction trans, CommandType cmdType, string cmdText, OracleParameter[] commandParameters)
        {

            //Open the connection if required
            if (conn.State != ConnectionState.Open)
                conn.Open();

            //Set up the command
            cmd.Connection = conn;
            cmd.CommandText = cmdText;
            cmd.CommandType = cmdType;

            //Bind it to the transaction if it exists
            if (trans != null)
                cmd.Transaction = trans;

            // Bind the parameters passed in
            if (commandParameters != null)
            {
                // 若参数Value值为null时，插入到数据库的值应该为DBNull.Value，且为ParameterDirection.Input
                foreach (OracleParameter parm in commandParameters)
                    if (parm.Value == null && parm.Direction == ParameterDirection.Input)
                    {
                        cmd.Parameters.Add(parm.ParameterName, parm.OracleType, parm.Size).Value = DBNull.Value;
                    }
                    else
                    {
                        cmd.Parameters.Add(parm);
                    }
            }
        }

        /// <summary>
        /// Internal function to prepare a command for execution by the database
        /// </summary>
        /// <param name="cmd">Existing command object</param>
        /// <param name="conn">Database connection object</param>
        /// <param name="trans">Optional transaction object</param>
        /// <param name="cmdType">Command type, e.g. stored procedure</param>
        /// <param name="cmdText">Command test</param>
        /// <param name="commandParameters">Parameters for the command</param>
        private static void PrepareCommand(OracleCommand cmd, OracleConnection conn, OracleTransaction trans, CommandType cmdType, string cmdText, IList commandParameters)
        {

            //Open the connection if required
            if (conn.State != ConnectionState.Open)
                conn.Open();

            //Set up the command
            cmd.Connection = conn;
            cmd.CommandText = cmdText;
            cmd.CommandType = cmdType;

            //Bind it to the transaction if it exists
            if (trans != null)
                cmd.Transaction = trans;

            // Bind the parameters passed in
            if (commandParameters != null)
            {
                // 若参数Value值为null时，插入到数据库的值应该为DBNull.Value，且为ParameterDirection.Input
                foreach (OracleParameter parm in commandParameters)
                    if (parm.Value == null && parm.Direction == ParameterDirection.Input)
                    {
                        cmd.Parameters.Add(parm.ParameterName, parm.OracleType, parm.Size).Value = DBNull.Value;
                    }
                    else
                    {
                        cmd.Parameters.Add(parm);
                    }
            }
        }
    }
}

 

4       代码示例

4.1   使用存储过程

      /// <summary>
        /// 新增
        /// </summary>
        /// <param name="v_dept">实体</param>
        /// <param name="re">返回ID</param>
        /// <param name="msg">返回消息</param>
        /// <returns></returns>
        private void executeWithOracleTrans(DEPT v_dept, ref int re, ref string msg)
        {
            try
            {
                OracleParameter[] paras = new OracleParameter[5];
                paras[0] = new OracleParameter("P_DEPTNO", OracleType.Number);
                paras[0].Value = v_dept.DEPTNO;
                paras[1] = new OracleParameter("P_DNAME", OracleType.VarChar);
                paras[1].Value = v_dept.DNAME;
                paras[2] = new OracleParameter("P_LOC", OracleType.VarChar);
                paras[2].Value = v_dept.LOC;
                paras[3] = new OracleParameter("X_RE", OracleType.Int32);
                paras[3].Direction = ParameterDirection.Output;
                paras[4] = new OracleParameter("X_MSG", OracleType.VarChar, 100);
                paras[4].Direction = ParameterDirection.Output;
 
               OracleHelper.ExecuteNonQuery(this.OracleConnectString, CommandType.StoredProcedure, "PKG_DEMO.Dept_Add", paras);
                re = Convert.ToInt32(paras[3].Value);
                msg = paras[4].Value.ToString();
            }
            catch (Exception ex)
            {
                re = 9;
                msg = ex.Message;
            }
        }

4.2   批处理之使用PL/SQL

      /// <summary>
        /// 用PL/SQL增加
        /// </summary>
        /// <param name="list_dept"></param>
        /// <param name="re"></param>
        /// <param name="msg"></param>
        private void executeWithPLSQL(IList<DEPT> list_dept, ref int re, ref string msg)
        {
            string sql = string.Empty;
            string insert_sql = string.Empty;
            List<OracleParameter> list_parm = new List<OracleParameter>();
            try
            {
                int i = 0;
                foreach (DEPT v_dept in list_dept)
                {
                    insert_sql += "insert into DEPT (DEPTNO, DNAME, LOC) values(:P_DEPTNO" + i + ", :P_DNAME" + i + ", :P_LOC" + i + ");";
                    OracleParameter[] paras = new OracleParameter[3];
                    paras[0] = new OracleParameter("P_DEPTNO" + i, OracleType.Number);
                    paras[0].Value = v_dept.DEPTNO;
                    paras[1] = new OracleParameter("P_DNAME" + i, OracleType.VarChar);
                    paras[1].Value = v_dept.DNAME;
                    paras[2] = new OracleParameter("P_LOC" + i, OracleType.VarChar);
                    paras[2].Value = v_dept.LOC;
                    list_parm.Add(paras[0]);
                    list_parm.Add(paras[1]);
                    list_parm.Add(paras[2]);
                    i++;
                }
                sql = "begin " +
                    insert_sql +
                  ":X_RE  := 1; " +
                  ":X_MSG := '提示：新增成功!'; " +
                  "commit; " +
                "exception " +
                  "when others then " +
                    "rollback; " +
                    ":X_RE  := 9; " +
                    ":X_MSG := '操作失败:[' || sqlcode || ':' || sqlerrm || ']'; " +
                "end; ";
                OracleParameter x_re = new OracleParameter("X_RE", OracleType.Int32);
                x_re.Direction = ParameterDirection.Output;
                OracleParameter x_msg = new OracleParameter("X_MSG", OracleType.VarChar, 100);
                x_msg.Direction = ParameterDirection.Output;
                list_parm.Add(x_re);
                list_parm.Add(x_msg);
                 OracleHelper.ExecuteNonQuery(this.OracleConnectString, CommandType.Text, sql, list_parm);
                re = Convert.ToInt32(x_re.Value);
                msg = x_msg.Value.ToString();
            }
            catch (Exception ex)
            {
                re = 9;
                msg = ex.Message;
            }
        }

 

4.3   批处理之使用事务

 

       /// <summary>
        /// 用事务新增
        /// </summary>
        /// <param name="list_dept"></param>
        /// <param name="re"></param>
        /// <param name="msg"></param>
        private void executeWithTrans(IList<DEPT> list_dept, ref int re, ref string msg)
        {
            // 启用事务进行控制
            OracleTransaction myTrans = OracleHelper.GetTrans(this.OracleConnectString);
            OracleConnection conn = myTrans.Connection;
            try
            {
                string sql = string.Empty;
                foreach (DEPT o in list_dept)
                {
                    sql = "insert into DEPT(DEPTNO,DNAME,LOC) values(:P_DEPTNO,:P_DNAME,:P_LOC)";
                    OracleParameter[] paras = new OracleParameter[3];
                    paras[0] = new OracleParameter("P_DEPTNO", OracleType.Int32);
                    paras[0].Value = o.DEPTNO;
                    paras[1] = new OracleParameter("P_DNAME", OracleType.VarChar);
                    paras[1].Value = o.DNAME;
                    paras[2] = new OracleParameter("P_LOC", OracleType.VarChar);
                    paras[2].Value = o.LOC;
                    OracleHelper.ExecuteNonQuery(myTrans, CommandType.Text, sql, paras);
                }
                myTrans.Commit();
                re = 1;
            }
            catch (Exception ex)
            {
                myTrans.Rollback();
                re = 9;
                msg = ex.Message;
            }
            finally
            {
                conn.Close();
            }
        }

5       运行效果

 

6       小结

学好.Net，从PetShop开始。

源代码下载：

https://files.cnblogs.com/yongfeng/HowToConnectDataBase.rar

数据库存储过程下载：

https://files.cnblogs.com/yongfeng/Package.rar

PDF下载：

https://files.cnblogs.com/yongfeng/20130301.rar

录像下载：

https://files.cnblogs.com/yongfeng/Media.rar