用于学习目的的 SQL Express Edition、SQL Compact Editin 和 SQLCMD

Question

我想从我在这里听说过的一些 SQL 教程网站学习 SQL 编程，但我需要一些环境来执行查询。我想我的计算机上同时安装了 SQL CE 和 SQL EE，但我对这些 DBMS 有一些疑问，我不确切知道如何使用 SQLCMD 实用程序，所以我希望这里有人有时间并会向我解释以下内容：

1234563速成版名称？

1. 我可以通过我的 C# (VC# Express) 应用程序交付和使用数据库，该应用程序是使用 SQL EE（嵌入式？）创建的？

1234563想要使用 SQL 我很想避免 DBMS 的图形工具）？

2. 如果您有其他建议，请告诉我，关于在学习如何使用 SQL 编程时我应该更好地使用什么，或者我现在应该坚持上述建议。

提前致谢。

Answer 1

您将需要使用 Microsoft SQL Server Management Studio Express。这要容易得多，您可以保存查询。您可以直接从 microsoft 下载，只需 google 即可。

要将它与自定义程序一起使用，用户还必须安装 Express，除非您将数据库转换为其他内容。许多使用 SQL Server 数据库制作程序的公司在他们的产品中包含 SQL Express 的一部分。

w3schools 是开始学习 SQL 的好地方。

Answer 2

SQL 入门的好地方是sql zoo

Answer 3

我做了一个小程序：SqlCdm 类似但用于 SDF 文件。 这是代码，下面是一个简单的测试。

我的程序的使用说明如下：

SqlCeCmd: [--create-database] [--shrink-database] --connection-string <connection_string> -f <sql_file>
  if create-database flag is present, it will be created for you.
  if shrink-database is present, the database will be shrinked.
WARNING: only one sqlfile can be provided

可能是SqlCmd 支持吧？但是这里的任何方式都是代码

SqlCeCmd.cs：

using System;
using System.Collections.Generic;
using System.Text;
using System.Data.SqlServerCe;
using System.Data.Common;
using System.Data;
using System.IO;

namespace SqlCeCmd
{
  /// <summary>
  /// A basic SqlCeCmd to be an equivalent to SqlCmd but for sdf files.
  /// </summary>
  public static class SqlCeCmd
  {

    private static void showUsage()
    {
      Console.Out.WriteLine("SqlCeCmd: [--create-database] [--shrink-database] --connection-string <connection_string> -f <sql_file>");
      Console.Out.WriteLine("  if create-database flag is present, it will be created for you.");
      Console.Out.WriteLine("  if shrink-database is present, the database will be shrinked.");
      Console.Out.WriteLine("WARNING: only one sqlfile can be provided");
    }

    /// <summary>
    /// The main entry point for the application.
    /// </summary>
    [STAThread]
    static void Main(string[] args)
    {
      if (args.Length == 0)
      {
        showUsage();
        return;
      }

      // parsing arguments
      string connectionString = "";
      string sqlFile = "";
      bool createDatabase = false;
      bool shrinkDatabase = false;


      bool nextIsConnectionString = false;
      bool nextIsSqlFile = false;
      foreach (string arg in args)
      {

        // ConnectionString
        if (nextIsConnectionString)
        {
          connectionString = arg;
          nextIsConnectionString = false;
        }
        if (arg.Equals("--connection-string"))
          nextIsConnectionString = true;

        // SqlFile
        if (nextIsSqlFile)
        {
          sqlFile = arg;
          nextIsSqlFile = false;
        }
        if (arg.Equals("-f"))
          nextIsSqlFile = true;

        if (arg.Equals("--create-database"))
          createDatabase = true;
        if (arg.Equals("--shrink-database"))
          shrinkDatabase = true;

      }

      if (connectionString == "")
      {
        Console.Out.WriteLine("error: can't find --connection-string <connection_string>");
        showUsage();
        return;
      }

      if (!createDatabase && sqlFile == "")
      {
        Console.Out.WriteLine("error: can't find -f <sql_file>");
        showUsage();
        return;
      }

      // creating database?
      if (createDatabase)
        createSdfDatabase(connectionString);
      if (shrinkDatabase)
        shrinkSdfDatabase(connectionString);

      // executing queies
      if (sqlFile != "")
      {
        Console.Out.WriteLine("connectionString: " + connectionString);
        Console.Out.WriteLine("sqlFile: " + sqlFile);
        executeSqlFile(connectionString, sqlFile);
      }
    }

    private static void createSdfDatabase(string connectionString)
    {
      Console.Out.WriteLine("Creating database: " + connectionString);
      new SqlCeEngine(connectionString).CreateDatabase();
    }
    private static void shrinkSdfDatabase(string connectionString)
    {
      Console.Out.WriteLine("Shrinking database: " + connectionString);
      new SqlCeEngine(connectionString).Shrink();
    }

    public static void executeSqlFile(String connectionString, String sqlFile)
    {

      IDbConnection cn = new SqlCeConnection(connectionString);
      cn.Open();
      string lastQuery = ""; // for debug only
      try
      {
        foreach (string query in splitCaseInsensitive(readWholeFile(sqlFile), "go"))
        {
          if (!query.Trim().Equals(""))
          {
            lastQuery = query;
            executeSqlQuery(cn, query);
          }
        }
      }
      catch (Exception e)
      {
        Console.Out.WriteLine("error: executing " + lastQuery);
        Console.Out.WriteLine("-----------------------------");
        Console.Out.WriteLine(e.StackTrace);
        Console.Out.WriteLine("-----------------------------");
      }
      finally
      {
        cn.Close();
      }
    }

    private static void executeSqlQuery(IDbConnection cn, string query)
    {
      IDbCommand cmd = new SqlCeCommand(query);
      cmd.Connection = cn;
      cmd.CommandType = CommandType.Text;
      cmd.ExecuteNonQuery();
    }


    // ************************
    // Util
    // ************************
    public static String[] split(String text, String delimiter)
    {
      return split(text, delimiter, false);
    }

    public static String[] splitCaseInsensitive(String text, String delimiter)
    {
      return split(text, delimiter, true);
    }

    private static String[] split(String text, String delimiter, bool caseSensitive)
    {
      List<String> splitted = new List<String>();
      String remaining = text;

      while (remaining.IndexOf(delimiter) > -1)
      {
        splitted.Add(leftMost(remaining, delimiter));
        remaining = right(remaining, delimiter);
      }
      splitted.Add(remaining);

      return splitted.ToArray();
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="expression">The string to split</param>
    /// <param name="delimiter">The splitting delimiter</param>
    /// <returns>The left most part of the string</returns>
    public static string leftMost(string expression, string delimiter)
    {
      int index = expression.IndexOf(delimiter);
      if (index > 0)
      {
        return expression.Substring(0, index);
      }
      return "";
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="expression">The string to split</param>
    /// <param name="delimiter">The splitting delimiter</param>
    /// <returns>Return the right part of an expression</returns>
    public static string right(string expression, string delimiter)
    {
      int index = expression.IndexOf(delimiter);
      if (index > -1 && index < (expression.Length - 1))
      {
        return expression.Substring(index + delimiter.Length, expression.Length - index - delimiter.Length);
      }
      return "";
    }

    /// <summary>
    /// Read the whole file and return its content
    /// </summary>
    /// <param name="path">path for existing file used to read from</param>
    /// <returns>The whole content of the file</returns>
    public static string readWholeFile(string path)
    {
      StreamReader reader = File.OpenText(path);
      string content = reader.ReadToEnd();
      reader.Close();
      return content;
    }
  }
}

TestSqlCeCmd.bat：

@echo off

:: Creating the Test.sql file
echo create table test (id int, test nvarchar(100)) > Test.sql
echo go >> Test.sql
echo create table test2 (id int, test nvarchar(100)) >> Test.sql

rm -f Test.sdf
SqlCeCmd.exe --create-database --connection-string "data source='Test.sdf'; mode=Exclusive; LCID=3084" -f "Test.sql"

:: an error should be raised here
:: SqlCeCmd.exe --connection-string "data source='Test.sdf'; mode=Exclusive; LCID=3084" -f Test.sql

pause