EF Core启动时偶发System.InvalidOperationException异常排查求助

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2026-7-9

EF Core启动阶段偶发Sequence contains no matching elements异常

问题现象

使用EF Core将LINQ表达式转换为SQL时，仅在Web应用通过dotnet run刚启动时偶发抛出System.InvalidOperationException，提示Sequence contains no matching elements。异常触发于以下代码段：

var results = await qry
    .AsNoTracking()
    .AsSplitQuery()
    .ToListAsync();

其中qry为IQueryable<Street>类型，调试确认DbContext和DbSet<Street>均不为空且未被释放。预期的LINQ转换逻辑如下：

DbSet<Street>()
     .Include(p => p.LocalBoard)
         .ThenInclude(p => p.City)
     .Where(prop => prop.Name.ToLower().Contains(string.IsNullOrEmpty(<>c__DisplayClass1_0.filter.Name) ? prop.Name.ToLower() : <>c__DisplayClass1_0.filter.Name.ToLower()) 
         && prop.LocalBoardID == <>c__DisplayClass1_0.filter.LocalBoardID != null ? <>c__DisplayClass1_0.filter.LocalBoardID.Value : prop.LocalBoardID
     )
     .Where(r => r.DeleteDate == null)
     .Select(r => r)
     .OrderBy(p => p.Name)

未使用.Single()、.First()这类会触发序列匹配的方法，异常仅在启动阶段偶发，当前环境为.NET 7.0 + EF Core 7.0.11。

补充信息

完整查询代码

var qry = context.Street
    .Include(p => p.LocalBoard)
        .ThenInclude(p => p.City)     
    .Where(prop => prop.Name.ToLower().Contains(String.IsNullOrEmpty(filter.Name) ? prop.Name.ToLower() : filter.Name.ToLower())
        && prop.LocalBoardID == (filter.LocalBoardID != null ? filter.LocalBoardID.Value : prop.LocalBoardID)
    )
    .Where(r => r.DeleteDate == null)
    .Select(r => r)     
    .OrderBy(p => p.Name)
    .AsNoTracking()
    .AsSplitQuery()
    .ToListAsync();

完整异常堆栈跟踪

Exception thrown: 'System.InvalidOperationException' in System.Private.CoreLib.dll: 'Sequence contains no matching element'
at System.Linq.ThrowHelper.ThrowNoMatchException()
at System.Linq.Enumerable.First[TSource](IEnumerable`1 source, Func`2 predicate)
at Microsoft.EntityFrameworkCore.Query.SqlExpressions.SelectExpression..ctor(IEntityType entityType, ISqlExpressionFactory sqlExpressionFactory)
at Microsoft.EntityFrameworkCore.Query.SqlExpressionFactory.Select(IEntityType entityType)
at Microsoft.EntityFrameworkCore.Query.RelationalQueryableMethodTranslatingExpressionVisitor.CreateShapedQueryExpression(IEntityType entityType)
at Microsoft.EntityFrameworkCore.Query.QueryableMethodTranslatingExpressionVisitor.VisitExtension(Expression extensionExpression)
at Microsoft.EntityFrameworkCore.Query.RelationalQueryableMethodTranslatingExpressionVisitor.VisitExtension(Expression extensionExpression)
at Microsoft.EntityFrameworkCore.SqlServer.Query.Internal.SqlServerQueryableMethodTranslatingExpressionVisitor.VisitExtension(Expression extensionExpression)
at Microsoft.EntityFrameworkCore.Query.QueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.RelationalQueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.QueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.RelationalQueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.QueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.RelationalQueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.QueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.RelationalQueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.QueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.RelationalQueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.QueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.RelationalQueryableMethodTranslatingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression)
at Microsoft.EntityFrameworkCore.Query.QueryCompilationContext.CreateQueryExecutor[TResult](Expression query)
at Microsoft.EntityFrameworkCore.Storage.Database.CompileQuery[TResult](Expression query, Boolean async)
at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.CompileQueryCore[TResult](IDatabase database, Expression query, IModel model, Boolean async)
at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.<>c__DisplayClass12_0`1.<ExecuteAsync>b__0()
at Microsoft.EntityFrameworkCore.Query.Internal.CompiledQueryCache.GetOrAddQuery[TResult](Object cacheKey, Func`1 compiler)
at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.ExecuteAsync[TResult](Expression query, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Query.Internal.EntityQueryProvider.ExecuteAsync[TResult](Expression expression, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Query.Internal.EntityQueryable`1.GetAsyncEnumerator(CancellationToken cancellationToken)
at System.Runtime.CompilerServices.ConfiguredCancelableAsyncEnumerable`1.GetAsyncEnumerator()
at Microsoft.EntityFrameworkCore.EntityFrameworkQueryableExtensions.<ToListAsync>d__65`1.MoveNext()
at MyProject_api.Domain.Services.ApiLogic.Sequential.MSSQL.ActiveDatabase.Core.RServiceCore`3.<GetAsync>d__18.MoveNext() in E:\Goran\Development\MyProject\MyProject-api\Domain\Services\ApiLogic\Sequential\MSSQL\ActiveDatabase\Core\RServiceCore.cs:line 194

实体类定义

Street类

[Table("Street")]
public class Street
{
    [Key]
    public int ID { get; set; }

    [Required]
    [MaxLength(124)]
    public string Name { get; set; }

    [Required]
    public int LocalBoardID { get; set; }
    [ForeignKey("LocalBoardID")]
    public virtual LocalBoard LocalBoard { get; set; }

    [Required]
    public int UserID { get; set; }
    [ForeignKey("UserID")]
    public virtual User User { get; set; }

    public DateTime? DeleteDate { get; set; }

    [JsonIgnore]
    public virtual ICollection<Person> People { get; set; }
}

LocalBoard类

[Table("LocalBoard")]
public class LocalBoard
{
    [Key]
    public int ID { get; set; }

    [Required]
    [MaxLength(250)]
    public string Name { get; set; }

    [Required]
    [MaxLength(10)]
    public string IdentificationNumber { get; set; }
    
    [Required]
    public int CityID { get; set; }
    [ForeignKey("CityID")]
    public virtual City City { get; set; }
    
    [Required]
    public int UserID { get; set; }
    [ForeignKey("UserID")]
    public virtual User User { get; set; }

    public DateTime? DeleteDate { get; set; }

    [JsonIgnore]
    public virtual ICollection<Person> People { get; set; }

    [JsonIgnore]
    public virtual ICollection<Street> Streets { get; set; }
}

City类

[Table("City")]
public class City
{
    [Key]
    public int ID { get; set; }

    [Required]
    [MaxLength(250)]
    public string Name { get; set; }
    
    [Required]
    [MaxLength(8)]
    public string PostCode { get; set; }

    [Required]
    public int UserID { get; set; }
    [ForeignKey("UserID")]
    public virtual User User { get; set; }

    public DateTime? DeleteDate { get; set; }

    [JsonIgnore]
    public virtual ICollection<LocalBoard> LocalBoards { get; set; }

    [JsonIgnore]
    public virtual ICollection<Person> People { get; set; }
}

排查与解决方向

元数据加载竞争：从堆栈看，异常发生在EF Core构建SelectExpression时调用Enumerable.First找不到匹配元素，大概率是启动阶段模型元数据未完全加载就执行查询导致。可在应用启动时提前初始化DbContext并预热模型，比如在Program.cs中添加await context.Database.EnsureCreatedAsync()或触发一次空查询。
LINQ表达式优化：原查询条件存在语法歧义，比如prop.LocalBoardID == (filter.LocalBoardID != null ? filter.LocalBoardID.Value : prop.LocalBoardID)，可重构为更简洁的逻辑，避免EF Core解析异常：
```
.Where(prop => 
    (string.IsNullOrEmpty(filter.Name) || prop.Name.ToLower().Contains(filter.Name.ToLower()))
    && (filter.LocalBoardID == null || prop.LocalBoardID == filter.LocalBoardID.Value)
)
```
版本bug修复：EF Core 7.0.11存在启动阶段查询编译的已知竞争问题，升级到.NET 7最新补丁版本（如7.0.15）或直接升级到.NET 8可修复此类偶发问题。
DbContext生命周期检查：若启动阶段存在多个DbContext实例并行操作，可能导致元数据缓存冲突，需确保DbContext使用Scoped生命周期，避免启动时创建多个并行实例。

内容的提问来源于stack exchange，提问作者Goran Petrović

EF Core启动时偶发System.InvalidOperationException异常排查求助

问题现象 #

补充信息 #

完整查询代码 #

完整异常堆栈跟踪 #

实体类定义 #