From 41ed895e1a7acdbb996ac88a41d40245202adfe5 Mon Sep 17 00:00:00 2001
From: sunkaixuan <610262374@qq.com>
Date: Mon, 26 Jun 2017 00:44:27 +0800
Subject: [PATCH] Update MySql

---
 .../SqlBuilderProvider/UpdateBuilder.cs       |  4 +-
 .../MySql/SqlBuilder/MySqlUpdateBuilder.cs    | 87 ++++++++++++++++++-
 2 files changed, 88 insertions(+), 3 deletions(-)

diff --git a/Src/Asp.Net/SqlSugar/Abstract/SqlBuilderProvider/UpdateBuilder.cs b/Src/Asp.Net/SqlSugar/Abstract/SqlBuilderProvider/UpdateBuilder.cs
index 11374ea30..ced2886fd 100644
--- a/Src/Asp.Net/SqlSugar/Abstract/SqlBuilderProvider/UpdateBuilder.cs
+++ b/Src/Asp.Net/SqlSugar/Abstract/SqlBuilderProvider/UpdateBuilder.cs
@@ -142,7 +142,7 @@ namespace SqlSugar
             }
         }
 
-        private string TomultipleSqlString(List<IGrouping<int, DbColumnInfo>> groupList)
+        protected virtual string TomultipleSqlString(List<IGrouping<int, DbColumnInfo>> groupList)
         {
             Check.Exception(PrimaryKeys == null || PrimaryKeys.Count == 0, " Update List<T> need Primary key");
             int pageSize = 200;
@@ -204,7 +204,7 @@ namespace SqlSugar
             return batchUpdateSql.ToString();
         }
 
-        private string ToSingleSqlString(List<IGrouping<int, DbColumnInfo>> groupList)
+        protected virtual string ToSingleSqlString(List<IGrouping<int, DbColumnInfo>> groupList)
         {
             string columnsString = string.Join(",", groupList.First().Where(it => it.IsPrimarykey == false && (it.IsIdentity == false || (IsOffIdentity && it.IsIdentity))).Select(it =>
             {
diff --git a/Src/Asp.Net/SqlSugar/Realization/MySql/SqlBuilder/MySqlUpdateBuilder.cs b/Src/Asp.Net/SqlSugar/Realization/MySql/SqlBuilder/MySqlUpdateBuilder.cs
index a886c55f9..1e15b645c 100644
--- a/Src/Asp.Net/SqlSugar/Realization/MySql/SqlBuilder/MySqlUpdateBuilder.cs
+++ b/Src/Asp.Net/SqlSugar/Realization/MySql/SqlBuilder/MySqlUpdateBuilder.cs
@@ -1,6 +1,91 @@
-namespace SqlSugar
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace SqlSugar
 {
     public class MySqlUpdateBuilder : UpdateBuilder
     {
+        public override string SqlTemplateBatch
+        {
+            get
+            {
+                return @"UPDATE  {1} S {2}   INNER JOIN ${{0}}  SET {0} ";
+            }
+        }
+        public override string SqlTemplateJoin
+        {
+            get
+            {
+                return @"            (
+              {0}
+
+            ) T ON {1}
+                 ";
+            }
+        }
+        protected override string TomultipleSqlString(List<IGrouping<int, DbColumnInfo>> groupList)
+        {
+            Check.Exception(PrimaryKeys == null || PrimaryKeys.Count == 0, " Update List<T> need Primary key");
+            int pageSize = 200;
+            int pageIndex = 1;
+            int totalRecord = groupList.Count;
+            int pageCount = (totalRecord + pageSize - 1) / pageSize;
+            StringBuilder batchUpdateSql = new StringBuilder();
+            while (pageCount >= pageIndex)
+            {
+                StringBuilder updateTable = new StringBuilder();
+                string setValues = string.Join(",", groupList.First().Where(it => it.IsPrimarykey == false && (it.IsIdentity == false || (IsOffIdentity && it.IsIdentity))).Select(it =>
+                {
+                    if (SetValues.IsValuable())
+                    {
+                        var setValue = SetValues.Where(sv => sv.Key == Builder.GetTranslationColumnName(it.DbColumnName));
+                        if (setValue != null && setValue.Any())
+                        {
+                            return setValue.First().Value;
+                        }
+                    }
+                    var result = string.Format("S.{0}=T.{0}", Builder.GetTranslationColumnName(it.DbColumnName));
+                    return result;
+                }));
+                batchUpdateSql.AppendFormat(SqlTemplateBatch.ToString(), setValues, GetTableNameStringNoWith, TableWithString);
+                int i = 0;
+                foreach (var columns in groupList.Skip((pageIndex - 1) * pageSize).Take(pageSize).ToList())
+                {
+                    var isFirst = i == 0;
+                    if (!isFirst)
+                    {
+                        updateTable.Append(SqlTemplateBatchUnion);
+                    }
+                    updateTable.Append("\r\n SELECT " + string.Join(",", columns.Select(it => string.Format(SqlTemplateBatchSelect, FormatValue(it.Value), it.DbColumnName))));
+                    ++i;
+                }
+                pageIndex++;
+                updateTable.Append("\r\n");
+                string whereString = null;
+                if (this.WhereValues.IsValuable())
+                {
+                    foreach (var item in WhereValues)
+                    {
+                        var isFirst = whereString == null;
+                        whereString += (isFirst ? null : " AND ");
+                        whereString += item;
+                    }
+                }
+                else if (PrimaryKeys.IsValuable())
+                {
+                    foreach (var item in PrimaryKeys)
+                    {
+                        var isFirst = whereString == null;
+                        whereString += (isFirst ? null : " AND ");
+                        whereString += string.Format("S.{0}=T.{0}", Builder.GetTranslationColumnName(item));
+                    }
+                }
+                var format= string.Format(SqlTemplateJoin, updateTable, whereString);
+                batchUpdateSql.Replace("${0}",format);
+                batchUpdateSql.Append(";");
+            }
+            return batchUpdateSql.ToString();
+        }
     }
 }