From 56d2128726fbc33b806edd719973e526f5c0f620 Mon Sep 17 00:00:00 2001
From: 2881099 <2881099@qq.com>
Date: Tue, 2 Feb 2021 13:07:01 +0800
Subject: [PATCH] =?UTF-8?q?-=20=E4=BC=98=E5=8C=96=20FreeSql.Extensions.Lin?=
 =?UTF-8?q?q=20Select=20=E9=80=89=E5=AE=9A=E5=AD=97=E6=AE=B5=E6=9F=A5?=
 =?UTF-8?q?=E8=AF=A2=E6=96=B9=E6=B3=95=EF=BC=9B#674=20#533?=
MIME-Version: 1.0
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---
 FreeSql.Tests/FreeSql.Tests/UnitTest5.cs           |  6 ++++++
 .../SelectProvider/Select0Provider.cs              | 14 ++++++++++++--
 .../SelectProvider/Select0ProviderReader.cs        |  9 +++++++++
 3 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/FreeSql.Tests/FreeSql.Tests/UnitTest5.cs b/FreeSql.Tests/FreeSql.Tests/UnitTest5.cs
index 917dc93f..a8c3b9df 100644
--- a/FreeSql.Tests/FreeSql.Tests/UnitTest5.cs
+++ b/FreeSql.Tests/FreeSql.Tests/UnitTest5.cs
@@ -24,6 +24,12 @@ namespace FreeSql.Tests
 
             Assert.Equal(@"SELECT count(distinct a.""status"") as1 
 FROM ""ts_up_dywhere01"" a", sql);
+
+            sql = fsql.Select<ts_up_dywhere01>().Select(a => new { a.status }).Distinct().ToSql();
+            fsql.Select<ts_up_dywhere01>().Select(a => new { a.status }).Distinct().Count(out count);
+
+            Assert.Equal(@"SELECT DISTINCT a.""status"" as1 
+FROM ""ts_up_dywhere01"" a", sql);
         }
 
         [Fact]
diff --git a/FreeSql/Internal/CommonProvider/SelectProvider/Select0Provider.cs b/FreeSql/Internal/CommonProvider/SelectProvider/Select0Provider.cs
index 38f19ac3..75a75ceb 100644
--- a/FreeSql/Internal/CommonProvider/SelectProvider/Select0Provider.cs
+++ b/FreeSql/Internal/CommonProvider/SelectProvider/Select0Provider.cs
@@ -698,18 +698,23 @@ namespace FreeSql.Internal.CommonProvider
             var tmpOrderBy = _orderby;
             var tmpSkip = _skip;
             var tmpLimit = _limit;
+            var tmpDistinct = _distinct;
             _orderby = null; //解决 select count(1) from t order by id 这样的 SQL 错误
             _skip = 0;
             _limit = 0;
+            _distinct = false;
             try
             {
-                return this.ToList<int>($"count(1){_commonUtils.FieldAsAlias("as1")}").Sum(); //这里的 Sum 为了分表查询
+                var countField = "1";
+                if (tmpDistinct && _selectExpression != null) countField = $"distinct {this.GetExpressionField(_selectExpression, FieldAliasOptions.AsProperty).field}";
+                return this.ToList<int>($"count({countField}){_commonUtils.FieldAsAlias("as1")}").Sum(); //这里的 Sum 为了分表查询
             }
             finally
             {
                 _orderby = tmpOrderBy;
                 _skip = tmpSkip;
                 _limit = tmpLimit;
+                _distinct = tmpDistinct;
             }
         }
         public TSelect Count(out long count)
@@ -741,18 +746,23 @@ namespace FreeSql.Internal.CommonProvider
             var tmpOrderBy = _orderby;
             var tmpSkip = _skip;
             var tmpLimit = _limit;
+            var tmpDistinct = _distinct;
             _orderby = null;
             _skip = 0;
             _limit = 0;
+            _distinct = false;
             try
             {
-                return (await this.ToListAsync<int>($"count(1){_commonUtils.FieldAsAlias("as1")}", cancellationToken)).Sum(); //这里的 Sum 为了分表查询
+                var countField = "1";
+                if (tmpDistinct && _selectExpression != null) countField = $"distinct {this.GetExpressionField(_selectExpression, FieldAliasOptions.AsProperty).field}";
+                return (await this.ToListAsync<int>($"count({countField}){_commonUtils.FieldAsAlias("as1")}", cancellationToken)).Sum(); //这里的 Sum 为了分表查询
             }
             finally
             {
                 _orderby = tmpOrderBy;
                 _skip = tmpSkip;
                 _limit = tmpLimit;
+                _distinct = tmpDistinct;
             }
         }
         public virtual Task<List<T1>> ToListAsync(bool includeNestedMembers = false, CancellationToken cancellationToken = default)
diff --git a/FreeSql/Internal/CommonProvider/SelectProvider/Select0ProviderReader.cs b/FreeSql/Internal/CommonProvider/SelectProvider/Select0ProviderReader.cs
index 2ff30188..e0a432a4 100644
--- a/FreeSql/Internal/CommonProvider/SelectProvider/Select0ProviderReader.cs
+++ b/FreeSql/Internal/CommonProvider/SelectProvider/Select0ProviderReader.cs
@@ -516,6 +516,15 @@ namespace FreeSql.Internal.CommonProvider
         static EventHandler<Aop.AuditDataReaderEventArgs> _OldAuditDataReaderHandler;
         public GetAllFieldExpressionTreeInfo GetAllFieldExpressionTreeLevel2()
         {
+            if (_selectExpression != null) //ToSql
+            {
+                var af = this.GetExpressionField(_selectExpression);
+                return new GetAllFieldExpressionTreeInfo
+                {
+                    Field = af.field,
+                    Read = (dr, idx) => throw new Exception("GetAllFieldExpressionTreeInfo.Read Is Null")
+                };
+            }
             if (_OldAuditDataReaderHandler != _orm.Aop.AuditDataReaderHandler)
             {
                 _OldAuditDataReaderHandler = _orm.Aop.AuditDataReaderHandler; //清除单表 ExppressionTree