项目 6 数据存储：仿冒 SqlClient（T-SQL 转写成 SQLite）、数据库页面、DataGridView、DateTimePicker

- 每个学生一套数据库，长期保存（data/databases/<用户编号>/库名.db）；学生程序运行时挂进沙箱可读写 - Sim.Data：SqlConnection / SqlCommand / SqlDataReader / SqlDataAdapter / SqlCommandBuilder / SqlParameter；连接字符串只按库名打开学生自己的库；ScriptDom 解析 T-SQL 后按白名单转写成 SQLite 语句， STRICT 表 + 元数据表还原 SQL Server 的列类型，报错编号和中文信息与 SQL Server 一致； INSERT 不写列名时跳过自增列，日期统一格式（书上 DateTime.ToString() 拼接的日期能正确比较） - 常驻 SQL 服务（Sim.Runner sql-server）：数据库页面的查询、对象资源管理器，评分前按实验 database.sql 建库 - 数据库页面（代替 SSMS）：对象资源管理器、查询窗口、编辑前 200 行、表设计器、恢复实验初始数据 - DataGridView（绑定 DataView/DataTable/DataSet，单元格修改写回 DataTable）、DateTimePicker；设计器工具箱加入 - 评分：每个检查项一份新建的实验库；新增点 / 修改表格单元格、选日期、表格里有 / 没有某行的检查 - 示例：项目 6 任务 2、3；时间格式改成和中文 Windows 一致（9:05:03）；异常堆栈不暴露服务器路径 - 测试：数据库端到端、接口（每人只看到自己的库、恢复实验数据）、评分出错情况、T-SQL 生成 Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-23 09:18:56 +08:00
1 parent 6b088240da
commit 670abe5921
@@ -0,0 +1,302 @@
+using System.Collections;
+using System.Collections.Generic;
+using System.Data.Common;
+using System.Linq;
+using Sim.Data.Engine;
+
+namespace System.Data.SqlClient;
+
+/// <summary>执行 T-SQL 语句。一条命令里可以有多条语句（用分号或换行分开）</summary>
+public sealed class SqlCommand : DbCommand, ICloneable
+{
+    private SqlConnection? _connection;
+    private string _commandText = "";
+    private CommandType _commandType = CommandType.Text;
+
+    public SqlCommand() { }
+
+    public SqlCommand(string cmdText) => CommandText = cmdText;
+
+    public SqlCommand(string cmdText, SqlConnection connection) : this(cmdText) => Connection = connection;
+
+    public SqlCommand(string cmdText, SqlConnection connection, SqlTransaction transaction) : this(cmdText, connection) => Transaction = transaction;
+
+    [Diagnostics.CodeAnalysis.AllowNull]
+    public override string CommandText
+    {
+        get => _commandText;
+        set => _commandText = value ?? "";
+    }
+
+    public override int CommandTimeout { get; set; } = 30;
+
+    public override CommandType CommandType
+    {
+        get => _commandType;
+        set => _commandType = value;
+    }
+
+    public new SqlConnection? Connection
+    {
+        get => _connection;
+        set => _connection = value;
+    }
+
+    protected override DbConnection? DbConnection
+    {
+        get => _connection;
+        set => _connection = (SqlConnection?)value;
+    }
+
+    public new SqlParameterCollection Parameters { get; } = new();
+    protected override DbParameterCollection DbParameterCollection => Parameters;
+
+    public new SqlTransaction? Transaction { get; set; }
+
+    protected override DbTransaction? DbTransaction
+    {
+        get => Transaction;
+        set => Transaction = (SqlTransaction?)value;
+    }
+
+    public override bool DesignTimeVisible { get; set; } = true;
+    public override UpdateRowSource UpdatedRowSource { get; set; } = UpdateRowSource.Both;
+
+    public override int ExecuteNonQuery() => Run(nameof(ExecuteNonQuery)).RecordsAffected;
+
+    public override object? ExecuteScalar()
+    {
+        var result = Run(nameof(ExecuteScalar));
+        return result.Results.Count > 0 && result.Results[0].Rows.Count > 0 ? result.Results[0].Rows[0][0] : null;
+    }
+
+    public new SqlDataReader ExecuteReader() => ExecuteReader(CommandBehavior.Default);
+
+    public new SqlDataReader ExecuteReader(CommandBehavior behavior) =>
+        new(Run(nameof(ExecuteReader)), behavior.HasFlag(CommandBehavior.CloseConnection) ? _connection : null);
+
+    protected override DbDataReader ExecuteDbDataReader(CommandBehavior behavior) => ExecuteReader(behavior);
+
+    public override void Cancel() { }
+    public override void Prepare() { }
+
+    public new SqlParameter CreateParameter() => new();
+    protected override DbParameter CreateDbParameter() => CreateParameter();
+
+    public SqlCommand Clone()
+    {
+        var clone = new SqlCommand(_commandText, _connection!) { CommandType = _commandType, CommandTimeout = CommandTimeout, Transaction = Transaction };
+        foreach (SqlParameter parameter in Parameters) clone.Parameters.Add(parameter.Clone());
+        return clone;
+    }
+
+    object ICloneable.Clone() => Clone();
+
+    private BatchResult Run(string operation)
+    {
+        if (_connection == null) throw new InvalidOperationException($"{operation}: Connection 属性尚未初始化。");
+        var session = _connection.Session(operation);
+        if (string.IsNullOrWhiteSpace(_commandText)) throw new InvalidOperationException($"{operation}: CommandText 属性尚未初始化");
+        if (_commandType == CommandType.StoredProcedure) throw SqlException.NotSupported("存储过程");
+        try
+        {
+            return session.Execute(_commandText, name =>
+            {
+                var parameter = Parameters.Find(name);
+                return parameter == null ? (false, null) : (true, parameter.Value);
+            });
+        }
+        catch (SqlException ex)
+        {
+            throw ex.Rethrow();
+        }
+    }
+}
+
+public sealed class SqlParameter : DbParameter, ICloneable
+{
+    private SqlDbType _sqlDbType = SqlDbType.NVarChar;
+    private bool _typeSet;
+    private string _parameterName = "";
+    private string _sourceColumn = "";
+
+    public SqlParameter() { }
+
+    public SqlParameter(string parameterName, object? value)
+    {
+        ParameterName = parameterName;
+        Value = value;
+    }
+
+    public SqlParameter(string parameterName, SqlDbType dbType)
+    {
+        ParameterName = parameterName;
+        SqlDbType = dbType;
+    }
+
+    public SqlParameter(string parameterName, SqlDbType dbType, int size) : this(parameterName, dbType) => Size = size;
+
+    public SqlParameter(string parameterName, SqlDbType dbType, int size, string sourceColumn) : this(parameterName, dbType, size) => SourceColumn = sourceColumn;
+
+    [Diagnostics.CodeAnalysis.AllowNull]
+    public override string ParameterName
+    {
+        get => _parameterName;
+        set => _parameterName = value ?? "";
+    }
+
+    public override object? Value { get; set; }
+
+    public SqlDbType SqlDbType
+    {
+        get => _sqlDbType;
+        set
+        {
+            _sqlDbType = value;
+            _typeSet = true;
+        }
+    }
+
+    public override DbType DbType
+    {
+        get => _sqlDbType switch
+        {
+            SqlDbType.Int => DbType.Int32,
+            SqlDbType.BigInt => DbType.Int64,
+            SqlDbType.SmallInt => DbType.Int16,
+            SqlDbType.TinyInt => DbType.Byte,
+            SqlDbType.Bit => DbType.Boolean,
+            SqlDbType.Float => DbType.Double,
+            SqlDbType.Real => DbType.Single,
+            SqlDbType.Decimal or SqlDbType.Money => DbType.Decimal,
+            SqlDbType.DateTime or SqlDbType.SmallDateTime or SqlDbType.Date => DbType.DateTime,
+            SqlDbType.VarBinary or SqlDbType.Image or SqlDbType.Binary => DbType.Binary,
+            SqlDbType.UniqueIdentifier => DbType.Guid,
+            SqlDbType.VarChar or SqlDbType.Char or SqlDbType.Text => DbType.AnsiString,
+            _ => DbType.String,
+        };
+        set => SqlDbType = value switch
+        {
+            DbType.Int32 => SqlDbType.Int,
+            DbType.Int64 => SqlDbType.BigInt,
+            DbType.Int16 => SqlDbType.SmallInt,
+            DbType.Byte => SqlDbType.TinyInt,
+            DbType.Boolean => SqlDbType.Bit,
+            DbType.Double => SqlDbType.Float,
+            DbType.Single => SqlDbType.Real,
+            DbType.Decimal or DbType.Currency => SqlDbType.Decimal,
+            DbType.DateTime or DbType.Date => SqlDbType.DateTime,
+            DbType.Binary => SqlDbType.VarBinary,
+            DbType.Guid => SqlDbType.UniqueIdentifier,
+            DbType.AnsiString => SqlDbType.VarChar,
+            _ => SqlDbType.NVarChar,
+        };
+    }
+
+    public override ParameterDirection Direction { get; set; } = ParameterDirection.Input;
+    public override bool IsNullable { get; set; }
+    public override int Size { get; set; }
+    public new byte Precision { get; set; }
+    public new byte Scale { get; set; }
+
+    [Diagnostics.CodeAnalysis.AllowNull]
+    public override string SourceColumn
+    {
+        get => _sourceColumn;
+        set => _sourceColumn = value ?? "";
+    }
+
+    public override bool SourceColumnNullMapping { get; set; }
+    public override DataRowVersion SourceVersion { get; set; } = DataRowVersion.Current;
+
+    public override void ResetDbType()
+    {
+        _sqlDbType = SqlDbType.NVarChar;
+        _typeSet = false;
+    }
+
+    internal bool TypeSet => _typeSet;
+
+    public SqlParameter Clone() => new(_parameterName, Value)
+    {
+        _sqlDbType = _sqlDbType,
+        _typeSet = _typeSet,
+        Direction = Direction,
+        Size = Size,
+        SourceColumn = SourceColumn,
+        SourceVersion = SourceVersion,
+        SourceColumnNullMapping = SourceColumnNullMapping,
+        IsNullable = IsNullable,
+    };
+
+    object ICloneable.Clone() => Clone();
+
+    public override string ToString() => _parameterName;
+}
+
+public sealed class SqlParameterCollection : DbParameterCollection
+{
+    private readonly List<SqlParameter> _items = new();
+
+    public override int Count => _items.Count;
+    public override object SyncRoot => this;
+
+    public new SqlParameter this[int index]
+    {
+        get => _items[index];
+        set => _items[index] = value;
+    }
+
+    public new SqlParameter this[string parameterName]
+    {
+        get => Find(parameterName) ?? throw new IndexOutOfRangeException($"此 SqlParameterCollection 中未包含带有 ParameterName“{parameterName}”的 SqlParameter。");
+        set => _items[IndexOf(parameterName)] = value;
+    }
+
+    /// <summary>按名字找参数，"@id" 和 "id" 视为同一个（和 SqlClient 一样不区分大小写）</summary>
+    internal SqlParameter? Find(string name)
+    {
+        var bare = name.TrimStart('@');
+        return _items.FirstOrDefault(p => string.Equals(p.ParameterName.TrimStart('@'), bare, StringComparison.OrdinalIgnoreCase));
+    }
+
+    public SqlParameter Add(SqlParameter value)
+    {
+        _items.Add(value ?? throw new ArgumentNullException(nameof(value)));
+        return value;
+    }
+
+    public override int Add(object value)
+    {
+        Add(value as SqlParameter ?? throw new InvalidCastException("SqlParameterCollection 只接受非空的 SqlParameter 类型对象。"));
+        return _items.Count - 1;
+    }
+
+    public SqlParameter Add(string parameterName, SqlDbType sqlDbType) => Add(new SqlParameter(parameterName, sqlDbType));
+    public SqlParameter Add(string parameterName, SqlDbType sqlDbType, int size) => Add(new SqlParameter(parameterName, sqlDbType, size));
+    public SqlParameter Add(string parameterName, SqlDbType sqlDbType, int size, string sourceColumn) => Add(new SqlParameter(parameterName, sqlDbType, size, sourceColumn));
+    public SqlParameter AddWithValue(string parameterName, object? value) => Add(new SqlParameter(parameterName, value));
+
+    public override void AddRange(Array values)
+    {
+        foreach (var value in values) Add(value);
+    }
+
+    public void AddRange(SqlParameter[] values) => AddRange((Array)values);
+
+    public override void Clear() => _items.Clear();
+    public override bool Contains(object value) => value is SqlParameter p && _items.Contains(p);
+    public override bool Contains(string value) => Find(value) != null;
+    public override void CopyTo(Array array, int index) => ((ICollection)_items).CopyTo(array, index);
+    public override IEnumerator GetEnumerator() => _items.GetEnumerator();
+    public override int IndexOf(object value) => value is SqlParameter p ? _items.IndexOf(p) : -1;
+    public override int IndexOf(string parameterName) => Find(parameterName) is { } p ? _items.IndexOf(p) : -1;
+    public override void Insert(int index, object value) => _items.Insert(index, (SqlParameter)value);
+    public override void Remove(object value) => _items.Remove((SqlParameter)value);
+    public override void RemoveAt(int index) => _items.RemoveAt(index);
+    public override void RemoveAt(string parameterName) => _items.RemoveAt(IndexOf(parameterName));
+    protected override DbParameter GetParameter(int index) => _items[index];
+    protected override DbParameter GetParameter(string parameterName) => this[parameterName];
+    protected override void SetParameter(int index, DbParameter value) => _items[index] = (SqlParameter)value;
+    protected override void SetParameter(string parameterName, DbParameter value) => this[parameterName] = (SqlParameter)value;
+}
@@ -0,0 +1,169 @@
+using System.Collections.Generic;
+using System.Data.Common;
+using Sim.Data.Engine;
+
+namespace System.Data.SqlClient;
+
+/// <summary>
+/// 数据库连接。连接字符串里的服务器名、账号、密码都不检查（书上的长服务器名、"." 都能连上），
+/// 只按 Initial Catalog（或 Database）打开这个学生自己的同名数据库；不写时连到 master。
+/// </summary>
+public sealed class SqlConnection : DbConnection, ICloneable
+{
+    private static readonly HashSet<string> KnownKeywords = new(StringComparer.OrdinalIgnoreCase)
+    {
+        "data source", "server", "address", "addr", "network address", "initial catalog", "database", "user id", "uid", "user",
+        "password", "pwd", "integrated security", "trusted_connection", "persist security info", "persistsecurityinfo",
+        "connect timeout", "connection timeout", "timeout", "pooling", "max pool size", "min pool size", "multipleactiveresultsets",
+        "encrypt", "trustservercertificate", "application name", "app", "workstation id", "wsid", "packet size",
+        "asynchronous processing", "async", "user instance", "attachdbfilename", "connection lifetime", "load balance timeout", "current language", "language",
+    };
+
+    private string _connectionString = "";
+    private ConnectionState _state = ConnectionState.Closed;
+    private Session? _session;
+
+    public SqlConnection() { }
+
+    public SqlConnection(string connectionString) => ConnectionString = connectionString;
+
+    [Diagnostics.CodeAnalysis.AllowNull]
+    public override string ConnectionString
+    {
+        get => _connectionString;
+        set
+        {
+            if (_state != ConnectionState.Closed) throw new InvalidOperationException("不允许更改“ConnectionString”属性。连接的当前状态为打开。");
+            _connectionString = value ?? "";
+        }
+    }
+
+    public override string Database => _session?.Database ?? Setting("initial catalog", "database") ?? DatabaseStore.Master;
+    public override string DataSource => Setting("data source", "server", "address", "addr", "network address") ?? "";
+    public override string ServerVersion => "10.50.1600";
+    public override ConnectionState State => _state;
+    public override int ConnectionTimeout => 15;
+    public string WorkstationId => Environment.MachineName;
+
+    /// <summary>连接打开时的数据库会话（平台内部使用）</summary>
+    internal Session Session(string operation) =>
+        _state == ConnectionState.Open && _session != null
+            ? _session
+            : throw new InvalidOperationException($"{operation} 要求已打开且可用的连接。连接的当前状态为已关闭。");
+
+    public override void Open()
+    {
+        if (_state == ConnectionState.Open) throw new InvalidOperationException("连接未关闭。连接的当前状态为打开。");
+        CheckKeywords();
+        var store = DatabaseStore.FromEnvironment()
+            ?? throw new SqlException(-1, "在与 SQL Server 建立连接时出现与网络相关的或特定于实例的错误：这次运行没有准备数据库。");
+        try
+        {
+            _session = new Session(store, Database);
+        }
+        catch (SqlException ex)
+        {
+            throw ex.Rethrow();
+        }
+        SetState(ConnectionState.Open);
+    }
+
+    public override void Close()
+    {
+        if (_session == null) return;
+        _session.Dispose();
+        _session = null;
+        SetState(ConnectionState.Closed);
+    }
+
+    public override void ChangeDatabase(string databaseName) => Session("ChangeDatabase").ChangeDatabase(databaseName);
+
+    public new SqlCommand CreateCommand() => new() { Connection = this };
+
+    protected override DbCommand CreateDbCommand() => CreateCommand();
+
+    public new SqlTransaction BeginTransaction() => BeginTransaction(IsolationLevel.ReadCommitted);
+
+    public new SqlTransaction BeginTransaction(IsolationLevel iso)
+    {
+        Session("BeginTransaction").BeginTransaction();
+        return new SqlTransaction(this, iso);
+    }
+
+    protected override DbTransaction BeginDbTransaction(IsolationLevel isolationLevel) => BeginTransaction(isolationLevel);
+
+    public object Clone() => new SqlConnection(_connectionString);
+
+    public static void ClearAllPools() { }
+    public static void ClearPool(SqlConnection connection) { }
+
+    protected override void Dispose(bool disposing)
+    {
+        if (disposing) Close();
+        base.Dispose(disposing);
+    }
+
+    private void SetState(ConnectionState state)
+    {
+        var original = _state;
+        _state = state;
+        OnStateChange(new StateChangeEventArgs(original, state));
+    }
+
+    private string? Setting(params string[] keys)
+    {
+        var builder = Parse();
+        foreach (var key in keys)
+            if (builder.TryGetValue(key, out var value) && value?.ToString() is { Length: > 0 } text) return text.Trim();
+        return null;
+    }
+
+    private DbConnectionStringBuilder Parse()
+    {
+        try
+        {
+            return new DbConnectionStringBuilder { ConnectionString = _connectionString };
+        }
+        catch (ArgumentException)
+        {
+            throw new ArgumentException("初始化字符串的格式不符合从索引 0 处开始的规范。");
+        }
+    }
+
+    private void CheckKeywords()
+    {
+        foreach (string key in Parse().Keys)
+            if (!KnownKeywords.Contains(key)) throw new ArgumentException($"不支持关键字:“{key}”。");
+        if (Setting("attachdbfilename") != null) throw new SqlException(-1, "平台不支持 AttachDbFilename：请用 Initial Catalog 指定数据库名。");
+    }
+}
+
+public sealed class SqlTransaction : DbTransaction
+{
+    private readonly SqlConnection _connection;
+    private bool _done;
+
+    internal SqlTransaction(SqlConnection connection, IsolationLevel isolationLevel)
+    {
+        _connection = connection;
+        IsolationLevel = isolationLevel;
+    }
+
+    public new SqlConnection Connection => _connection;
+    protected override DbConnection DbConnection => _connection;
+    public override IsolationLevel IsolationLevel { get; }
+
+    public override void Commit()
+    {
+        if (_done) throw new InvalidOperationException("此 SqlTransaction 已完成；它再也无法使用。");
+        _done = true;
+        _connection.Session("Commit").Commit();
+    }
+
+    public override void Rollback()
+    {
+        if (_done) throw new InvalidOperationException("此 SqlTransaction 已完成；它再也无法使用。");
+        _done = true;
+        _connection.Session("Rollback").Rollback();
+    }
+}
@@ -0,0 +1,120 @@
+using System.Data.Common;
+
+namespace System.Data.SqlClient;
+
+public delegate void SqlRowUpdatingEventHandler(object sender, SqlRowUpdatingEventArgs e);
+public delegate void SqlRowUpdatedEventHandler(object sender, SqlRowUpdatedEventArgs e);
+
+public sealed class SqlRowUpdatingEventArgs : RowUpdatingEventArgs
+{
+    public SqlRowUpdatingEventArgs(DataRow row, IDbCommand? command, StatementType statementType, DataTableMapping tableMapping)
+        : base(row, command, statementType, tableMapping) { }
+
+    public new SqlCommand? Command
+    {
+        get => (SqlCommand?)base.Command;
+        set => base.Command = value;
+    }
+}
+
+public sealed class SqlRowUpdatedEventArgs : RowUpdatedEventArgs
+{
+    public SqlRowUpdatedEventArgs(DataRow row, IDbCommand? command, StatementType statementType, DataTableMapping tableMapping)
+        : base(row, command, statementType, tableMapping) { }
+
+    public new SqlCommand? Command => (SqlCommand?)base.Command;
+}
+
+/// <summary>在数据库和 DataSet 之间搬运数据：Fill 读出来，Update 把 DataTable 里改过的行写回去</summary>
+public sealed class SqlDataAdapter : DbDataAdapter, ICloneable
+{
+    public SqlDataAdapter() { }
+
+    public SqlDataAdapter(SqlCommand selectCommand) => SelectCommand = selectCommand;
+
+    public SqlDataAdapter(string selectCommandText, SqlConnection selectConnection) => SelectCommand = new SqlCommand(selectCommandText, selectConnection);
+
+    public SqlDataAdapter(string selectCommandText, string selectConnectionString) =>
+        SelectCommand = new SqlCommand(selectCommandText, new SqlConnection(selectConnectionString));
+
+    public new SqlCommand? SelectCommand
+    {
+        get => (SqlCommand?)base.SelectCommand;
+        set => base.SelectCommand = value;
+    }
+
+    public new SqlCommand? InsertCommand
+    {
+        get => (SqlCommand?)base.InsertCommand;
+        set => base.InsertCommand = value;
+    }
+
+    public new SqlCommand? UpdateCommand
+    {
+        get => (SqlCommand?)base.UpdateCommand;
+        set => base.UpdateCommand = value;
+    }
+
+    public new SqlCommand? DeleteCommand
+    {
+        get => (SqlCommand?)base.DeleteCommand;
+        set => base.DeleteCommand = value;
+    }
+
+    public event SqlRowUpdatingEventHandler? RowUpdating;
+    public event SqlRowUpdatedEventHandler? RowUpdated;
+
+    protected override RowUpdatingEventArgs CreateRowUpdatingEvent(DataRow dataRow, IDbCommand? command, StatementType statementType, DataTableMapping tableMapping) =>
+        new SqlRowUpdatingEventArgs(dataRow, command, statementType, tableMapping);
+
+    protected override RowUpdatedEventArgs CreateRowUpdatedEvent(DataRow dataRow, IDbCommand? command, StatementType statementType, DataTableMapping tableMapping) =>
+        new SqlRowUpdatedEventArgs(dataRow, command, statementType, tableMapping);
+
+    protected override void OnRowUpdating(RowUpdatingEventArgs value) => RowUpdating?.Invoke(this, (SqlRowUpdatingEventArgs)value);
+
+    protected override void OnRowUpdated(RowUpdatedEventArgs value) => RowUpdated?.Invoke(this, (SqlRowUpdatedEventArgs)value);
+
+    object ICloneable.Clone() => new SqlDataAdapter { SelectCommand = SelectCommand, InsertCommand = InsertCommand, UpdateCommand = UpdateCommand, DeleteCommand = DeleteCommand };
+}
+
+/// <summary>按 SqlDataAdapter 的查询语句自动生成 INSERT / UPDATE / DELETE（要求查询包含主键列）</summary>
+public sealed class SqlCommandBuilder : DbCommandBuilder
+{
+    public SqlCommandBuilder()
+    {
+        QuotePrefix = "[";
+        QuoteSuffix = "]";
+    }
+
+    public SqlCommandBuilder(SqlDataAdapter adapter) : this() => DataAdapter = adapter;
+
+    public new SqlDataAdapter? DataAdapter
+    {
+        get => (SqlDataAdapter?)base.DataAdapter;
+        set => base.DataAdapter = value;
+    }
+
+    public new SqlCommand GetInsertCommand() => (SqlCommand)base.GetInsertCommand();
+    public new SqlCommand GetInsertCommand(bool useColumnsForParameterNames) => (SqlCommand)base.GetInsertCommand(useColumnsForParameterNames);
+    public new SqlCommand GetUpdateCommand() => (SqlCommand)base.GetUpdateCommand();
+    public new SqlCommand GetUpdateCommand(bool useColumnsForParameterNames) => (SqlCommand)base.GetUpdateCommand(useColumnsForParameterNames);
+    public new SqlCommand GetDeleteCommand() => (SqlCommand)base.GetDeleteCommand();
+    public new SqlCommand GetDeleteCommand(bool useColumnsForParameterNames) => (SqlCommand)base.GetDeleteCommand(useColumnsForParameterNames);
+
+    protected override void ApplyParameterInfo(DbParameter parameter, DataRow row, StatementType statementType, bool whereClause) { }
+
+    protected override string GetParameterName(int parameterOrdinal) => "@p" + parameterOrdinal.ToString(Globalization.CultureInfo.InvariantCulture);
+    protected override string GetParameterName(string parameterName) => "@" + parameterName;
+    protected override string GetParameterPlaceholder(int parameterOrdinal) => GetParameterName(parameterOrdinal);
+
+    public override string QuoteIdentifier(string unquotedIdentifier) => "[" + unquotedIdentifier.Replace("]", "]]") + "]";
+
+    protected override void SetRowUpdatingHandler(DbDataAdapter adapter)
+    {
+        if (adapter is not SqlDataAdapter sql) throw new InvalidOperationException("SqlCommandBuilder 只能用于 SqlDataAdapter。");
+        if (adapter == base.DataAdapter) sql.RowUpdating += Handler;
+        else sql.RowUpdating -= Handler;
+    }
+
+    private void Handler(object sender, SqlRowUpdatingEventArgs e) => RowUpdatingHandler(e);
+}
@@ -0,0 +1,211 @@
+using System.Collections;
+using System.Data.Common;
+using System.Globalization;
+using Sim.Data.Engine;
+
+namespace System.Data.SqlClient;
+
+/// <summary>按行读取查询结果（结果已在内存里，读的时候不再访问数据库）</summary>
+public sealed class SqlDataReader : DbDataReader
+{
+    private readonly BatchResult _batch;
+    private readonly SqlConnection? _closeConnection;
+    private int _resultIndex;
+    private int _row = -1;
+    private bool _closed;
+
+    internal SqlDataReader(BatchResult batch, SqlConnection? closeConnection)
+    {
+        _batch = batch;
+        _closeConnection = closeConnection;
+    }
+
+    private QueryResult? Current => _resultIndex < _batch.Results.Count ? _batch.Results[_resultIndex] : null;
+
+    private object[] Row
+    {
+        get
+        {
+            if (_closed) throw new InvalidOperationException("阅读器关闭时尝试调用 Read 无效。");
+            var current = Current;
+            if (current == null || _row < 0 || _row >= current.Rows.Count) throw new InvalidOperationException("不存在数据时进行无效的读取尝试。");
+            return current.Rows[_row];
+        }
+    }
+
+    public override int FieldCount => Current?.Columns.Count ?? 0;
+    public override bool HasRows => Current?.Rows.Count > 0;
+    public override bool IsClosed => _closed;
+    public override int RecordsAffected => _batch.RecordsAffected;
+    public override int Depth => 0;
+
+    public override object this[int ordinal] => GetValue(ordinal);
+    public override object this[string name] => GetValue(GetOrdinal(name));
+
+    public override bool Read()
+    {
+        if (_closed) throw new InvalidOperationException("阅读器关闭时尝试调用 Read 无效。");
+        var current = Current;
+        if (current == null) return false;
+        _row++;
+        return _row < current.Rows.Count;
+    }
+
+    public override bool NextResult()
+    {
+        _resultIndex++;
+        _row = -1;
+        return Current != null;
+    }
+
+    public override void Close()
+    {
+        if (_closed) return;
+        _closed = true;
+        _closeConnection?.Close();
+    }
+
+    public override string GetName(int ordinal) => Column(ordinal).Name;
+
+    public override int GetOrdinal(string name)
+    {
+        var columns = Current?.Columns ?? throw new IndexOutOfRangeException(name);
+        for (var i = 0; i < columns.Count; i++)
+            if (string.Equals(columns[i].Name, name, StringComparison.OrdinalIgnoreCase)) return i;
+        throw new IndexOutOfRangeException(name);
+    }
+
+    public override Type GetFieldType(int ordinal) => Column(ordinal).ClrType;
+    public override string GetDataTypeName(int ordinal) => Column(ordinal).Type?.Name ?? "sql_variant";
+
+    public override object GetValue(int ordinal)
+    {
+        Column(ordinal);
+        return Row[ordinal];
+    }
+
+    public override int GetValues(object[] values)
+    {
+        var row = Row;
+        var count = Math.Min(values.Length, row.Length);
+        Array.Copy(row, values, count);
+        return count;
+    }
+
+    public override bool IsDBNull(int ordinal) => GetValue(ordinal) is DBNull;
+
+    public override bool GetBoolean(int ordinal) => Cast<bool>(ordinal);
+    public override byte GetByte(int ordinal) => Cast<byte>(ordinal);
+    public override char GetChar(int ordinal) => throw new NotSupportedException("SqlDataReader 不支持 GetChar。");
+    public override DateTime GetDateTime(int ordinal) => Cast<DateTime>(ordinal);
+    public override decimal GetDecimal(int ordinal) => Cast<decimal>(ordinal);
+    public override double GetDouble(int ordinal) => Cast<double>(ordinal);
+    public override float GetFloat(int ordinal) => Cast<float>(ordinal);
+    public override Guid GetGuid(int ordinal) => Cast<Guid>(ordinal);
+    public override short GetInt16(int ordinal) => Cast<short>(ordinal);
+    public override int GetInt32(int ordinal) => Cast<int>(ordinal);
+    public override long GetInt64(int ordinal) => Cast<long>(ordinal);
+    public override string GetString(int ordinal) => Cast<string>(ordinal);
+
+    /// <summary>和 SqlClient 一样严格：列是 varchar 时 GetInt32 报"指定的转换无效"，是 NULL 时报"数据为空"</summary>
+    private T Cast<T>(int ordinal)
+    {
+        var value = GetValue(ordinal);
+        if (value is DBNull) throw new InvalidCastException("数据为空。不能对空值调用此方法或属性。");
+        if (value is T typed) return typed;
+        // 表达式列（如 count(*)）没有声明类型，数字之间可以互相转换
+        if (Column(ordinal).Type == null && value is IConvertible && typeof(T) != typeof(string))
+            return (T)Convert.ChangeType(value, typeof(T), CultureInfo.InvariantCulture);
+        throw new InvalidCastException("指定的转换无效。");
+    }
+
+    public override long GetBytes(int ordinal, long dataOffset, byte[]? buffer, int bufferOffset, int length)
+    {
+        var bytes = Cast<byte[]>(ordinal);
+        if (buffer == null) return bytes.Length;
+        var count = (int)Math.Min(length, bytes.Length - dataOffset);
+        if (count <= 0) return 0;
+        Array.Copy(bytes, dataOffset, buffer, bufferOffset, count);
+        return count;
+    }
+
+    public override long GetChars(int ordinal, long dataOffset, char[]? buffer, int bufferOffset, int length)
+    {
+        var text = Cast<string>(ordinal);
+        if (buffer == null) return text.Length;
+        var count = (int)Math.Min(length, text.Length - dataOffset);
+        if (count <= 0) return 0;
+        text.CopyTo((int)dataOffset, buffer, bufferOffset, count);
+        return count;
+    }
+
+    public override IEnumerator GetEnumerator() => new DbEnumerator(this, closeReader: false);
+
+    /// <summary>列的结构信息：DbDataAdapter 填充、SqlCommandBuilder 生成增删改语句时要用（主键、自增、来自哪张表的哪一列）</summary>
+    public override DataTable GetSchemaTable()
+    {
+        var table = new DataTable("SchemaTable");
+        table.Columns.Add(SchemaTableColumn.ColumnName, typeof(string));
+        table.Columns.Add(SchemaTableColumn.ColumnOrdinal, typeof(int));
+        table.Columns.Add(SchemaTableColumn.ColumnSize, typeof(int));
+        table.Columns.Add(SchemaTableColumn.NumericPrecision, typeof(short));
+        table.Columns.Add(SchemaTableColumn.NumericScale, typeof(short));
+        table.Columns.Add(SchemaTableColumn.IsUnique, typeof(bool));
+        table.Columns.Add(SchemaTableColumn.IsKey, typeof(bool));
+        table.Columns.Add(SchemaTableOptionalColumn.BaseServerName, typeof(string));
+        table.Columns.Add(SchemaTableOptionalColumn.BaseCatalogName, typeof(string));
+        table.Columns.Add(SchemaTableColumn.BaseColumnName, typeof(string));
+        table.Columns.Add(SchemaTableColumn.BaseSchemaName, typeof(string));
+        table.Columns.Add(SchemaTableColumn.BaseTableName, typeof(string));
+        table.Columns.Add(SchemaTableColumn.DataType, typeof(Type));
+        table.Columns.Add(SchemaTableColumn.AllowDBNull, typeof(bool));
+        table.Columns.Add(SchemaTableColumn.ProviderType, typeof(int));
+        table.Columns.Add(SchemaTableColumn.IsAliased, typeof(bool));
+        table.Columns.Add(SchemaTableColumn.IsExpression, typeof(bool));
+        table.Columns.Add("IsIdentity", typeof(bool));
+        table.Columns.Add(SchemaTableOptionalColumn.IsAutoIncrement, typeof(bool));
+        table.Columns.Add(SchemaTableOptionalColumn.IsRowVersion, typeof(bool));
+        table.Columns.Add(SchemaTableOptionalColumn.IsHidden, typeof(bool));
+        table.Columns.Add(SchemaTableColumn.IsLong, typeof(bool));
+        table.Columns.Add(SchemaTableOptionalColumn.IsReadOnly, typeof(bool));
+        table.Columns.Add("DataTypeName", typeof(string));
+
+        var columns = Current?.Columns ?? Array.Empty<ResultColumn>();
+        for (var i = 0; i < columns.Count; i++)
+        {
+            var c = columns[i];
+            var row = table.NewRow();
+            row[SchemaTableColumn.ColumnName] = c.Name;
+            row[SchemaTableColumn.ColumnOrdinal] = i;
+            row[SchemaTableColumn.ColumnSize] = c.Type?.MaxLength ?? (c.Type?.IsMax == true ? int.MaxValue : 0);
+            row[SchemaTableColumn.NumericPrecision] = (short)(c.Type?.Precision ?? 0);
+            row[SchemaTableColumn.NumericScale] = (short)(c.Type?.Scale ?? 0);
+            row[SchemaTableColumn.IsUnique] = c.IsKey;
+            row[SchemaTableColumn.IsKey] = c.IsKey;
+            row[SchemaTableColumn.BaseColumnName] = (object?)c.BaseColumn ?? DBNull.Value;
+            row[SchemaTableColumn.BaseSchemaName] = c.BaseTable != null ? "dbo" : DBNull.Value;
+            row[SchemaTableColumn.BaseTableName] = (object?)c.BaseTable ?? DBNull.Value;
+            row[SchemaTableColumn.DataType] = c.ClrType;
+            row[SchemaTableColumn.AllowDBNull] = c.AllowNull;
+            row[SchemaTableColumn.ProviderType] = 0;
+            row[SchemaTableColumn.IsAliased] = c.BaseColumn != null && !string.Equals(c.BaseColumn, c.Name, StringComparison.OrdinalIgnoreCase);
+            row[SchemaTableColumn.IsExpression] = c.BaseColumn == null;
+            row["IsIdentity"] = c.IsIdentity;
+            row[SchemaTableOptionalColumn.IsAutoIncrement] = c.IsIdentity;
+            row[SchemaTableOptionalColumn.IsRowVersion] = false;
+            row[SchemaTableOptionalColumn.IsHidden] = false;
+            row[SchemaTableColumn.IsLong] = c.Type is { IsMax: true } or { Name: "text" or "ntext" or "image" };
+            row[SchemaTableOptionalColumn.IsReadOnly] = c.IsIdentity || c.BaseColumn == null;
+            row["DataTypeName"] = c.Type?.Name ?? "sql_variant";
+            table.Rows.Add(row);
+        }
+        return table;
+    }
+
+    private ResultColumn Column(int ordinal)
+    {
+        var columns = Current?.Columns;
+        if (columns == null || ordinal < 0 || ordinal >= columns.Count) throw new IndexOutOfRangeException("索引超出了数组界限。");
+        return columns[ordinal];
+    }
+}
@@ -0,0 +1,60 @@
+using System.Data.Common;
+
+namespace System.Data.SqlClient;
+
+/// <summary>
+/// 数据库报错。Number 和 Message 与中文版 SQL Server 一致（如 208"对象名 'X' 无效。"），
+/// 学生在网上搜报错信息能找到对应的说明。
+/// </summary>
+public sealed class SqlException : DbException
+{
+    internal SqlException(int number, string message, int lineNumber = 1) : base(message, unchecked((int)0x80131904))
+    {
+        Number = number;
+        LineNumber = lineNumber;
+    }
+
+    public int Number { get; }
+    public int LineNumber { get; }
+    public byte Class => 16;
+    public byte State => 1;
+    public string Server => ".";
+    public string Procedure => "";
+
+    /// <summary>在 SqlClient 的公开方法里重新抛出：学生看到的调用栈从 SqlCommand.ExecuteNonQuery 等开始，不含平台内部的实现</summary>
+    internal SqlException Rethrow() => new(Number, Message, LineNumber);
+
+    public override string ToString() => $"{GetType().FullName} (0x80131904): {Message}{(StackTrace != null ? Environment.NewLine + StackTrace : "")}";
+
+    // ---------- 常见报错 ----------
+
+    internal static SqlException Syntax(string near, int line = 1) =>
+        new(102, IsKeyword(near) ? $"关键字 '{near}' 附近有语法错误。" : $"'{near}' 附近有语法错误。", line);
+
+    internal static SqlException InvalidObject(string name) => new(208, $"对象名 '{name}' 无效。");
+    internal static SqlException InvalidColumn(string name) => new(207, $"列名 '{name}' 无效。");
+    internal static SqlException AmbiguousColumn(string name) => new(209, $"列名 '{name}' 不明确。");
+    internal static SqlException ColumnCountMismatch() => new(213, "列名或所提供值的数目与表定义不匹配。");
+    internal static SqlException IdentityInsert(string table) => new(544, $"当 IDENTITY_INSERT 设置为 OFF 时，不能为表 '{table}' 中的标识列插入显式值。");
+    internal static SqlException NullNotAllowed(string column, string table) => new(515, $"不能将值 NULL 插入列 '{column}'，表 '{table}'；列不允许有 Null 值。INSERT 失败。");
+    internal static SqlException DuplicateKey(string table) => new(2627, $"违反了 PRIMARY KEY 约束。不能在对象 'dbo.{table}' 中插入重复键。");
+    internal static SqlException Truncated() => new(8152, "将截断字符串或二进制数据。");
+    internal static SqlException ConvertFailed(string value, string type) => new(245, $"在将 varchar 值 '{value}' 转换成数据类型 {type} 时失败。");
+    internal static SqlException DateConvertFailed() => new(241, "从字符串转换日期和/或时间时，转换失败。");
+    internal static SqlException ObjectExists(string name) => new(2714, $"数据库中已存在名为 '{name}' 的对象。");
+    internal static SqlException DatabaseExists(string name) => new(1801, $"数据库 '{name}' 已存在。请选择其他数据库名称。");
+    internal static SqlException CannotOpenDatabase(string name) => new(4060, $"无法打开登录所请求的数据库 \"{name}\"。登录失败。");
+    internal static SqlException DatabaseNotFound(string name) => new(911, $"数据库 '{name}' 不存在。请确保正确地输入了该名称。");
+    internal static SqlException DatabaseInUse(string name) => new(3702, $"无法删除数据库 \"{name}\"，因为该数据库当前正在使用。");
+    internal static SqlException CannotDropTable(string name) => new(3701, $"无法对 表 '{name}' 执行 删除，因为它不存在，或者您没有所需的权限。");
+    internal static SqlException UnknownFunction(string name) => new(195, $"'{name}' 不是可以识别的 内置函数名称。");
+    internal static SqlException UndeclaredVariable(string name) => new(137, $"必须声明标量变量 \"{name}\"。");
+    internal static SqlException DivideByZero() => new(8134, "遇到以零作除数错误。");
+    internal static SqlException NotSupported(string what) => new(40000, $"平台暂不支持 {what}。");
+
+    private static bool IsKeyword(string word) => word.ToUpperInvariant() is
+        "SELECT" or "FROM" or "WHERE" or "INSERT" or "INTO" or "VALUES" or "UPDATE" or "SET" or "DELETE" or "CREATE" or "TABLE"
+        or "DROP" or "ALTER" or "AND" or "OR" or "NOT" or "NULL" or "ORDER" or "GROUP" or "BY" or "HAVING" or "AS" or "ON"
+        or "JOIN" or "INNER" or "LEFT" or "RIGHT" or "OUTER" or "IS" or "IN" or "LIKE" or "BETWEEN" or "TOP" or "DISTINCT"
+        or "PRIMARY" or "KEY" or "IDENTITY" or "DEFAULT" or "DATABASE" or "USE" or "CASE" or "WHEN" or "THEN" or "ELSE" or "END";
+}