PGsql(PostgreSQL)的本地连接和远程连接的问题
刚接收一个项目，数据库是Pgsql,第一次使用这种数据库。安装pgsql后，调试项目时发现：Error: System.Data.Odbc.OdbcException (0x80131937): ERROR [IM002] [Microsoft][ODBC 驱动程序管理器] 未发现数据源名称并且未指定默认驱动程序。
好吧解决过程就不说了，直接说方法：这种问题大体分两种，第一，ODBC的问题，第二，配置文件的问题。先说第一，我本机的环境是win7，不知道为什么，pgsql的odbc驱动就是装不上，随后，我把驱动装到server2008服务器上，成功了。随后配置odbc,这里切记
务必把数据源配置到系统DSN中，至于为什么，你自己慢慢想吧。然后Data Source取决于你在
<add name="PGSQL1" connectionString="DSN=MAINDB" providerName="System.Data.Odbc"/>
connectionString="DSN=MaINDB"，好吧，这些是基础，我就不废话了。第一结束
再说第二，配置文件的问题，1.~\PostgreSQL\9.1\data\pg_hba.conf 2. ~\PostgreSQL\9.1\data\ postgresql.conf,要修改这两个文件。还是先说1：
TYPE DATABASE USER ADDRESS METHOD # IPv4 local connections: host all all 127.0.0.1/32 md5 host all all 192.168.1.107/32 md5
上面的host 是本机的配置，而下面的，则是你需要远程访问的ip，默认是木有的，你要自己添。2. 我的pgsql装好后，这个配置文件是正常的，也是可用的：
# - Connection Settings - listen_addresses = '*' # what IP address(es) to listen on; # comma-separated list of addresses; # defaults to 'localhost', '*' = all # (change requires restart) port = 5432 # (change requires restart) max_connections = 100 # (change requires restart)
所以我也没改。
第二也说完了
然后再说说远程访问的事，远程访问，你总不能还用odbc吧，好吧，这里就需要插件了， http://pgfoundry.org/frs/download.php/3226/Npgsql2.0.11.93-bin-ms.net4.0.zip ，这是传送门，或者你也可以根据你的.net版本下载（http://pgfoundry.org/frs/?group_id=1000140&release_id=958），有插件然后最好有个帮助类，好吧。
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using Npgsql;
using Mono.Security;
using System.Configuration;
using System.Data;
/// <summary>
///PgSqlHelper 的摘要说明
/// </summary>
namespace company.Helper{
public static class Conn
{
public static readonly string PgSqlConn = System.Configuration.ConfigurationManager.ConnectionStrings["connectionString"].ConnectionString;
}
public class PgSqlHelper
{
#region 私有构造函数和方法
private PgSqlHelper() { }
/// <summary>
/// 将NpgsqlParameter参数数组(参数值)分配给NpgsqlCommand命令.
/// 这个方法将给任何一个参数分配DBNull.Value;
/// 该操作将阻止默认值的使用.
/// </summary>
/// <param name="command">命令名</param>
/// <param name="commandParameters">NpgsqlParameters数组</param>
private static void AttachParameters(NpgsqlCommand command, NpgsqlParameter[] commandParameters)
{
if (command == null) throw new ArgumentNullException("command");
if (commandParameters != null)
{
foreach (NpgsqlParameter p in commandParameters)
{
if (p != null)
{
// 检查未分配值的输出参数,将其分配以DBNull.Value.
if ((p.Direction == ParameterDirection.InputOutput || p.Direction == ParameterDirection.Input) &&
(p.Value == null))
{
p.Value = DBNull.Value;
}
command.Parameters.Add(p);
}
}
}
}
/// <summary>
/// 将DataRow类型的列值分配到NpgsqlParameter参数数组.
/// </summary>
/// <param name="commandParameters">要分配值的NpgsqlParameter参数数组</param>
/// <param name="dataRow">将要分配给存储过程参数的DataRow</param>
private static void AssignParameterValues(NpgsqlParameter[] commandParameters, DataRow dataRow)
{
if ((commandParameters == null) || (dataRow == null))
{
return;
}
int i = 0;
// 设置参数值
foreach (NpgsqlParameter commandParameter in commandParameters)
{
// 创建参数名称,如果不存在,只抛出一个异常.
if (commandParameter.ParameterName == null ||
commandParameter.ParameterName.Length <= 1)
throw new Exception(
string.Format("请提供参数{0}一个有效的名称{1}.", i, commandParameter.ParameterName));
// 从dataRow的表中获取为参数数组中数组名称的列的索引.
// 如果存在和参数名称相同的列,则将列值赋给当前名称的参数.
if (dataRow.Table.Columns.IndexOf(commandParameter.ParameterName.Substring(1)) != -1)
commandParameter.Value = dataRow[commandParameter.ParameterName.Substring(1)];
i++;
}
}
/// <summary>
/// 将一个对象数组分配给NpgsqlParameter参数数组.
/// </summary>
/// <param name="commandParameters">要分配值的NpgsqlParameter参数数组</param>
/// <param name="parameterValues">将要分配给存储过程参数的对象数组</param>
private static void AssignParameterValues(NpgsqlParameter[] commandParameters, object[] parameterValues)
{
if ((commandParameters == null) || (parameterValues == null))
{
return;
}
// 确保对象数组个数与参数个数匹配,如果不匹配,抛出一个异常.
if (commandParameters.Length != parameterValues.Length)
{
throw new ArgumentException("参数值个数与参数不匹配.");
}
// 给参数赋值
for (int i = 0, j = commandParameters.Length; i < j; i++)
{
// If the current array value derives from IDbDataParameter, then assign its Value property
if (parameterValues[i] is IDbDataParameter)
{
IDbDataParameter paramInstance = (IDbDataParameter)parameterValues[i];
if (paramInstance.Value == null)
{
commandParameters[i].Value = DBNull.Value;
}
else
{
commandParameters[i].Value = paramInstance.Value;
}
}
else if (parameterValues[i] == null)
{
commandParameters[i].Value = DBNull.Value;
}
else
{
commandParameters[i].Value = parameterValues[i];
}
}
}
/// <summary>
/// 预处理用户提供的命令,数据库连接/事务/命令类型/参数
/// </summary>
/// <param name="command">要处理的NpgsqlCommand</param>
/// <param name="connection">数据库连接</param>
/// <param name="transaction">一个有效的事务或者是null值</param>
/// <param name="commandType">命令类型 (存储过程,命令文本, 其它.)</param>
/// <param name="commandText">存储过程名或都T-SQL命令文本</param>
/// <param name="commandParameters">和命令相关联的NpgsqlParameter参数数组,如果没有参数为'null'</param>
/// <param name="mustCloseConnection"><c>true</c> 如果连接是打开的,则为true,其它情况下为false.</param>
private static void PrepareCommand(NpgsqlCommand command, NpgsqlConnection connection, NpgsqlTransaction transaction, CommandType commandType, string commandText, NpgsqlParameter[] commandParameters, out bool mustCloseConnection)
{
if (command == null) throw new ArgumentNullException("command");
if (commandText == null || commandText.Length == 0) throw new ArgumentNullException("commandText");
// If the provided connection is not open, we will open it
if (connection.State != ConnectionState.Open)
{
mustCloseConnection = true;
connection.Open();
}
else
{
mustCloseConnection = false;
}
// 给命令分配一个数据库连接.
command.Connection = connection;
// 设置命令文本(存储过程名或SQL语句)
command.CommandText = commandText;
// 分配事务
if (transaction != null)
{
if (transaction.Connection == null) throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction");
command.Transaction = transaction;
}
// 设置命令类型.
command.CommandType = commandType;
// 分配命令参数
if (commandParameters != null)
{
AttachParameters(command, commandParameters);
}
return;
}
#endregion 私有构造函数和方法结束
#region ExecuteNonQuery命令
/// <summary>
/// 执行指定连接字符串,类型的NpgsqlCommand.
/// </summary>
/// <remarks>
/// 示例:
/// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders");
/// </remarks>
/// <param name="connectionString">一个有效的数据库连接字符串</param>
/// <param name="commandType">命令类型 (存储过程,命令文本, 其它.)</param>
/// <param name="commandText">存储过程名称或SQL语句</param>
/// <returns>返回命令影响的行数</returns>
public static int ExecuteNonQuery(string connectionString, CommandType commandType, string commandText)
{
return ExecuteNonQuery(connectionString, commandType, commandText, (NpgsqlParameter[])null);
}
/// <summary>
/// 执行指定连接字符串,类型的NpgsqlCommand.如果没有提供参数,不返回结果.
/// </summary>
/// <remarks>
/// 示例:
/// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new NpgsqlParameter("@prodid", 24));
/// </remarks>
/// <param name="connectionString">一个有效的数据库连接字符串</param>
/// <param name="commandType">命令类型 (存储过程,命令文本, 其它.)</param>
/// <param name="commandText">存储过程名称或SQL语句</param>
/// <param name="commandParameters">NpgsqlParameter参数数组</param>
/// <returns>返回命令影响的行数</returns>
public static int ExecuteNonQuery(string connectionString, CommandType commandType, string commandText, params NpgsqlParameter[] commandParameters)
{
if (connectionString == null || connectionString.Length == 0) throw new ArgumentNullException("connectionString");
using (NpgsqlConnection connection = new NpgsqlConnection(connectionString))
{
connection.Open();
return ExecuteNonQuery(connection, commandType, commandText, commandParameters);
}
}
/// <summary>
/// 执行指定数据库连接对象的命令
/// </summary>
/// <remarks>
/// 示例:
/// int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders");
/// </remarks>
/// <param name="connection">一个有效的数据库连接对象</param>
/// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
/// <param name="commandText">存储过程名称或T-SQL语句</param>
/// <returns>返回影响的行数</returns>
public static int ExecuteNonQuery(NpgsqlConnection connection, CommandType commandType, string commandText)
{
return ExecuteNonQuery(connection, commandType, commandText, (NpgsqlParameter[])null);
}
/// <summary>
/// 执行指定数据库连接对象的命令
/// </summary>
/// <remarks>
/// 示例:
/// int result = ExecuteNonQuery(conn, CommandType.StoredProcedure, "PublishOrders", new NpgsqlParameter("@prodid", 24));
/// </remarks>
/// <param name="connection">一个有效的数据库连接对象</param>
/// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
/// <param name="commandText">T存储过程名称或T-SQL语句</param>
/// <param name="commandParameters">SqlParamter参数数组</param>
/// <returns>返回影响的行数</returns>
public static int ExecuteNonQuery(NpgsqlConnection connection, CommandType commandType, string commandText, params NpgsqlParameter[] commandParameters)
{
if (connection == null) throw new ArgumentNullException("connection");
// 创建NpgsqlCommand命令,并进行预处理
NpgsqlCommand cmd = new NpgsqlCommand();
bool mustCloseConnection = false;
PrepareCommand(cmd, connection, (NpgsqlTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection);
// Finally, execute the command
int retval = cmd.ExecuteNonQuery();
// 清除参数,以便再次使用.
cmd.Parameters.Clear();
if (mustCloseConnection)
connection.Close();
return retval;
}
/// <summary>
/// 执行带事务的NpgsqlCommand.
/// </summary>
/// <remarks>
/// 示例.:
/// int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "PublishOrders");
/// </remarks>
/// <param name="transaction">一个有效的数据库连接对象</param>
/// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
/// <param name="commandText">存储过程名称或T-SQL语句</param>
/// <returns>返回影响的行数/returns>
public static int ExecuteNonQuery(NpgsqlTransaction transaction, CommandType commandType, string commandText)
{
return ExecuteNonQuery(transaction, commandType, commandText, (NpgsqlParameter[])null);
}
/// <summary>
/// 执行带事务的NpgsqlCommand(指定参数).
/// </summary>
/// <remarks>
/// 示例:
/// int result = ExecuteNonQuery(trans, CommandType.StoredProcedure, "GetOrders", new NpgsqlParameter("@prodid", 24));
/// </remarks>
/// <param name="transaction">一个有效的数据库连接对象</param>
/// <param name="commandType">命令类型(存储过程,命令文本或其它.)</param>
/// <param name="commandText">存储过程名称或T-SQL语句</param>
/// <param name="commandParameters">SqlParamter参数数组</param>
/// <returns>返回影响的行数</returns>
public static int ExecuteNonQuery(NpgsqlTransaction transaction, CommandType commandType, string commandText, params NpgsqlParameter[] commandParameters)
{
if (transaction == null) throw new ArgumentNullException("transaction");
if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction");
// 预处理
NpgsqlCommand cmd = new NpgsqlCommand();
bool mustCloseConnection = false;
PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection);
// 执行
int retval = cmd.ExecuteNonQuery();
// 清除参数集,以便再次使用.
cmd.Parameters.Clear();
return retval;
}
#endregion ExecuteNonQuery方法结束
#region ExecuteDataset方法
/// <summary>
/// 执行指定数据库连接字符串的命令,返回DataSet.
/// </summary>
/// <remarks>
/// 示例:
/// DataSet ds = ExecuteDataset(connString, CommandType.StoredProcedure, "GetOrders");
/// </remarks>
/// <param name="connectionString">一个有效的数据库连接字符串</param>
/// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
/// <param name="commandText">存储过程名称或T-SQL语句</param>
/// <returns>返回一个包含结果集的DataSet</returns>
public static DataSet ExecuteDataset(string connectionString, CommandType commandType, string commandText)
{
return ExecuteDataset(connectionString, commandType, commandText, (NpgsqlParameter[])null);
}
/// <summary>
/// 执行指定数据库连接字符串的命令,返回DataSet.
/// </summary>
/// <remarks>
/// 示例:
/// DataSet ds = ExecuteDataset(connString, CommandType.StoredProcedure, "GetOrders", new NpgsqlParameter("@prodid", 24));
/// </remarks>
/// <param name="connectionString">一个有效的数据库连接字符串</param>
/// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
/// <param name="commandText">存储过程名称或T-SQL语句</param>
/// <param name="commandParameters">SqlParamters参数数组</param>
/// <returns>返回一个包含结果集的DataSet</returns>
public static DataSet ExecuteDataset(string connectionString, CommandType commandType, string commandText, params NpgsqlParameter[] commandParameters)
{
if (connectionString == null || connectionString.Length == 0) throw new ArgumentNullException("connectionString");
// 创建并打开数据库连接对象,操作完成释放对象.
using (NpgsqlConnection connection = new NpgsqlConnection(connectionString))
{
connection.Open();
// 调用指定数据库连接字符串重载方法.
return ExecuteDataset(connection, commandType, commandText, commandParameters);
}
}
/// <summary>
/// 执行指定数据库连接对象的命令,返回DataSet.
/// </summary>
/// <remarks>
/// 示例:
/// DataSet ds = ExecuteDataset(conn, CommandType.StoredProcedure, "GetOrders");
/// </remarks>
/// <param name="connection">一个有效的数据库连接对象</param>
/// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
/// <param name="commandText">存储过程名或T-SQL语句</param>
/// <returns>返回一个包含结果集的DataSet</returns>
public static DataSet ExecuteDataset(NpgsqlConnection connection, CommandType commandType, string commandText)
{
return ExecuteDataset(connection, commandType, commandText, (NpgsqlParameter[])null);
}
/// <summary>
/// 执行指定数据库连接对象的命令,指定存储过程参数,返回DataSet.
/// </summary>
/// <remarks>
/// 示例:
/// DataSet ds = ExecuteDataset(conn, CommandType.StoredProcedure, "GetOrders", new NpgsqlParameter("@prodid", 24));
/// </remarks>
/// <param name="connection">一个有效的数据库连接对象</param>
/// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
/// <param name="commandText">存储过程名或T-SQL语句</param>
/// <param name="commandParameters">SqlParamter参数数组</param>
/// <returns>返回一个包含结果集的DataSet</returns>
public static DataSet ExecuteDataset(NpgsqlConnection connection, CommandType commandType, string commandText, params NpgsqlParameter[] commandParameters)
{
if (connection == null) throw new ArgumentNullException("connection");
// 预处理
NpgsqlCommand cmd = new NpgsqlCommand();
bool mustCloseConnection = false;
PrepareCommand(cmd, connection, (NpgsqlTransaction)null, commandType, commandText, commandParameters, out mustCloseConnection);
// 创建NpgsqlDataAdapter和DataSet.
using (NpgsqlDataAdapter da = new NpgsqlDataAdapter(cmd))
{
DataSet ds = new DataSet();
// 填充DataSet.
da.Fill(ds);
cmd.Parameters.Clear();
if (mustCloseConnection)
connection.Close();
return ds;
}
}
/// <summary>
/// 执行指定事务的命令,返回DataSet.
/// </summary>
/// <remarks>
/// 示例:
/// DataSet ds = ExecuteDataset(trans, CommandType.StoredProcedure, "GetOrders");
/// </remarks>
/// <param name="transaction">事务</param>
/// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
/// <param name="commandText">存储过程名或T-SQL语句</param>
/// <returns>返回一个包含结果集的DataSet</returns>
public static DataSet ExecuteDataset(NpgsqlTransaction transaction, CommandType commandType, string commandText)
{
return ExecuteDataset(transaction, commandType, commandText, (NpgsqlParameter[])null);
}
/// <summary>
/// 执行指定事务的命令,指定参数,返回DataSet.
/// </summary>
/// <remarks>
/// 示例:
/// DataSet ds = ExecuteDataset(trans, CommandType.StoredProcedure, "GetOrders", new NpgsqlParameter("@prodid", 24));
/// </remarks>
/// <param name="transaction">事务</param>
/// <param name="commandType">命令类型 (存储过程,命令文本或其它)</param>
/// <param name="commandText">存储过程名或T-SQL语句</param>
/// <param name="commandParameters">SqlParamter参数数组</param>
/// <returns>返回一个包含结果集的DataSet</returns>
public static DataSet ExecuteDataset(NpgsqlTransaction transaction, CommandType commandType, string commandText, params NpgsqlParameter[] commandParameters)
{
if (transaction == null) throw new ArgumentNullException("transaction");
if (transaction != null && transaction.Connection == null) throw new ArgumentException("The transaction was rollbacked or commited, please provide an open transaction.", "transaction");
// 预处理
NpgsqlCommand cmd = new NpgsqlCommand();
bool mustCloseConnection = false;
PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection);
// 创建 DataAdapter & DataSet
using (NpgsqlDataAdapter da = new NpgsqlDataAdapter(cmd))
{
DataSet ds = new DataSet();
da.Fill(ds);
cmd.Parameters.Clear();
return ds;
}
}
#endregion ExecuteDataset数据集命令结束
}
}
我自己改的sqlhelper，好吧，没什么技术含量。好吧，完了，就这样。
