update readme

FreeSql.Tests/FreeSql.Tests/UnitTest1.cs

@@ -344,9 +344,17 @@ namespace FreeSql.Tests
             public bool IsLeaf { get; set; }
         }
 
+        public static int GetUNIX_TIMESTAMP() => 0;
         [Fact]
         public void Test1()
         {
+            g.mysql.Aop.ParseExpression += new EventHandler<Aop.ParseExpressionEventArgs>((s, e) =>
+            {
+                if (e.Expression.NodeType == ExpressionType.Call && (e.Expression as MethodCallExpression).Method.Name == "GetUNIX_TIMESTAMP")
+                    e.Result = "UNIX_TIMESTAMP(NOW())";
+            });
+            var dkkdksdjgj = g.mysql.Select<TaskBuild>().Where(a => a.OptionsEntity04 > GetUNIX_TIMESTAMP()).ToSql();
+
             var kdkdfm = g.sqlite.Select<AnswerQuestionnaire>()
                 .Include(a => a.MedicalRecord)
                 .ToSql();

readme.md

@@ -65,7 +65,7 @@ IFreeSql fsql = new FreeSql.FreeSqlBuilder()
     .UseConnectionString(FreeSql.DataType.Sqlite, 
         @"Data Source=|DataDirectory|\document.db;Pooling=true;Max Pool Size=10")
     .UseAutoSyncStructure(true) //自动同步实体结构到数据库
-    .Build();
+    .Build(); //请务必定义成 Singleton 单例模式
 
 class Song {
     [Column(IsIdentity = true)]