[fix] 新增修改表结构时，清空tableNames缓存，便于上层快速感知新表。完善分表自动创建的逻辑，不创建默认表，首次写入时自动创建新分表

XCode/DataAccessLayer/DAL.cs

@@ -86,7 +86,7 @@ public partial class DAL
     public IAsyncDbSession AsyncSession => (Db as DbBase)!.CreateSessionForAsync();
 
     private String? _mapTo;
-    private readonly ICache _cache = new MemoryCache();
+    private static ICache _cache = new MemoryCache();
     #endregion
 
     #region 创建函数
@@ -634,7 +634,7 @@ public partial class DAL
     /// <summary>
     /// 获取所有表名，带缓存，不区分大小写
     /// </summary>
-    public ICollection<String> TableNames => _cache.GetOrAdd("tableNames", k => new HashSet<String>(GetTableNames(), StringComparer.OrdinalIgnoreCase), 60) ?? [];
+    public ICollection<String> TableNames => _cache.GetOrAdd($"tableNames:{ConnName}", k => new HashSet<String>(GetTableNames(), StringComparer.OrdinalIgnoreCase), 60) ?? [];
 
     /// <summary>
     /// 快速获取所有表名，无缓存，区分大小写
@@ -680,7 +680,7 @@ public partial class DAL
     /// <returns></returns>
     public static IList<IDataTable> Import(String xml)
     {
-        if (xml.IsNullOrEmpty()) return new IDataTable[0];
+        if (xml.IsNullOrEmpty()) return [];
 
         return ModelHelper.FromXml(xml, CreateTable);
     }
@@ -820,6 +820,10 @@ public partial class DAL
             span?.SetError(ex, null);
             throw;
         }
+        finally
+        {
+            _cache.Remove($"tableNames:{ConnName}");
+        }
     }
 
     private void FixIndexName(IDataTable table)

XUnitTest.XCode/EntityTests/TimeShardTests.cs

@@ -0,0 +1,44 @@
+using System;
+using System.IO;
+using NewLife;
+using XCode.Exceptions;
+using Xunit;
+using XUnitTest.XCode.TestEntity;
+
+namespace XUnitTest.XCode.EntityTests;
+
+public class TimeShardTests
+{
+    [Fact]
+    public void Test1()
+    {
+        var file = Setting.Current.DataPath.CombinePath("test.db");
+        if (File.Exists(file)) File.Delete(file);
+
+        //var dal = ExpressLogs.Meta.Session.Dal;
+        //var table = ExpressLogs.Meta.Table.DataTable;
+
+        //dal.SetTables(table);
+
+        // 对分表查行数，报错
+        Assert.Throws<XSqlException>(() => ExpressLogs.FindCount());
+
+        // 分表查询，没有数据
+        var time = DateTime.Now.AddHours(1);
+        var list = ExpressLogs.Search(time.Date, time, null, null);
+        Assert.Empty(list);
+
+        // 写入数据
+        var entity = new ExpressLogs
+        {
+            Code = "123456",
+        };
+        entity.Insert();
+
+        list = ExpressLogs.Search(time.Date, time, null, null);
+        Assert.Single(list);
+
+        //var n = ExpressLogs.Meta.Count;
+        //Assert.Equal(0, n);
+    }
+}

XUnitTest.XCode/TimeShardTests.cs

@@ -1,16 +0,0 @@
-using Xunit;
-
-using XUnitTest.XCode.TestEntity;
-
-namespace XUnitTest.XCode;
-
-public class TimeShardTests
-{
-    [Fact]
-    public void Test1()
-    {
-        var n = ExpressLogs.Meta.Count;
-
-        Assert.Equal(0, n);
-    }
-}