Add Subquery.SelectJoin

Src/Asp.Net/SqlSugar/ExpressionsToSql/DbMethods/DefaultDbMethod.cs

@@ -222,6 +222,11 @@ namespace SqlSugar
             }
         }
 
+        public virtual string GetStringJoinSelector(string result, string separator) 
+        {
+            return $"string_agg(({result})::text,'{separator}') ";
+        }
+
         public virtual string ToInt32(MethodCallExpressionModel model)
         {
             var parameter = model.Args[0];

Src/Asp.Net/SqlSugar/ExpressionsToSql/DbMethods/IDbMethods.cs

@@ -33,6 +33,7 @@ namespace SqlSugar
         string StartsWith(MethodCallExpressionModel model);
         string EndsWith(MethodCallExpressionModel model);
         string ToInt32(MethodCallExpressionModel model);
+        string GetStringJoinSelector(string result,string separator);
         string ToInt64(MethodCallExpressionModel model);
         string ToString(MethodCallExpressionModel model);
         string ToVarchar(MethodCallExpressionModel model); 

Src/Asp.Net/SqlSugar/ExpressionsToSql/Subquery/Items/SubSelectStringJoin.cs

@@ -0,0 +1,89 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Linq.Expressions;
+using System.Text;
+namespace SqlSugar 
+{
+    public class SubSelectStringJoin : ISubOperation
+    {
+        public bool HasWhere
+        {
+            get; set;
+        }
+
+        public string Name
+        {
+            get
+            {
+                return "SelectStringJoin";
+            }
+        }
+
+        public Expression Expression
+        {
+            get; set;
+        }
+
+
+        public int Sort
+        {
+            get
+            {
+                return 200;
+            }
+        }
+
+        public ExpressionContext Context
+        {
+            get; set;
+        }
+
+        public string GetValue(Expression expression = null)
+        {
+            var exp = expression as MethodCallExpression;
+            var entityType = (exp.Arguments[0] as LambdaExpression).Parameters[0].Type;
+            if (this.Context.InitMappingInfo != null)
+            {
+                this.Context.InitMappingInfo(entityType);
+                this.Context.RefreshMapping();
+            }
+            var result = "";
+            if (this.Context.JoinIndex == 0)
+                result = SubTools.GetMethodValue(this.Context, exp.Arguments[0], ResolveExpressType.FieldSingle);
+            else
+                result = SubTools.GetMethodValue(this.Context, exp.Arguments[0], ResolveExpressType.FieldMultiple);
+
+            SetShortName(exp, result);
+
+            result = this.Context.DbMehtods.GetStringJoinSelector(result, ExpressionTool.GetExpressionValue(exp.Arguments[1]) + "");
+
+            return result;
+        }
+
+        public void SetShortName(MethodCallExpression exp, string result)
+        {
+            if (exp.Arguments[0] is LambdaExpression && result.IsContainsIn("+", "-", "*", "/"))
+            {
+                var parameters = (exp.Arguments[0] as LambdaExpression).Parameters;
+                if (parameters != null && parameters.Count > 0)
+                {
+                    this.Context.CurrentShortName = this.Context.GetTranslationColumnName(parameters[0].ObjToString());
+                }
+
+            }
+        }
+        public void SetShortNameNext(MethodCallExpression exp, string result)
+        {
+            if (exp.Arguments.Count > 1 && exp.Arguments[1] is LambdaExpression && result.IsContainsIn("+", "-", "*", "/"))
+            {
+                var parameters = (exp.Arguments[1] as LambdaExpression).Parameters;
+                if (parameters != null && parameters.Count > 0)
+                {
+                    this.Context.CurrentShortName = this.Context.GetTranslationColumnName(parameters[0].ObjToString());
+                }
+
+            }
+        }
+    }
+}

Src/Asp.Net/SqlSugar/ExpressionsToSql/Subquery/SubTools.cs

@@ -35,7 +35,8 @@ namespace SqlSugar
                                                     new SubAs(){Context=Context},
                                                     new SubHaving(){  Context=Context},
                                                     new SubWithNolock(){ Context=Context },
-                                                    new SubEnableTableFilter(){ Context=Context }
+                                                    new SubEnableTableFilter(){ Context=Context },
+                                                    new SubSelectStringJoin{ Context=Context }
                                                 };
         }
 

Src/Asp.Net/SqlSugar/ExpressionsToSql/Subquery/Subquerable.cs

@@ -84,6 +84,11 @@ namespace SqlSugar
             return default(string);
         }
 
+        public string SelectStringJoin(Func<T, string> expression,string separator)
+        {
+            return default(string);
+        }
+
         public TResult Max<TResult>(Func<T, TResult> expression) where TResult : struct
         {
             return default(TResult);

Src/Asp.Net/SqlSugar/Realization/MySql/SqlBuilder/MySqlExpressionContext.cs

@@ -14,6 +14,10 @@ namespace SqlSugar
     }
     public class MySqlMethod : DefaultDbMethod, IDbMethods
     {
+        public override string GetStringJoinSelector(string result, string separator)
+        {
+            return $"group_concat({result}  separator '{separator}') ";
+        }
         public override string DateDiff(MethodCallExpressionModel model)
         {
             var parameter = model.Args[0];

Src/Asp.Net/SqlSugar/Realization/Oracle/SqlBuilder/OracleExpressionContext.cs

@@ -57,6 +57,10 @@ namespace SqlSugar
     }
     public partial class OracleMethod : DefaultDbMethod, IDbMethods
     {
+        public override string GetStringJoinSelector(string result, string separator)
+        {
+            return $"listagg(to_char({result}),'{separator}') within group(order by {result}) ";
+        }
         public override string HasValue(MethodCallExpressionModel model)
         {
             var parameter = model.Args[0];

Src/Asp.Net/SqlSugar/Realization/Sqlite/SqlBuilder/SqliteExpressionContext.cs

@@ -14,6 +14,10 @@ namespace SqlSugar
     }
     public class SqliteMethod : DefaultDbMethod, IDbMethods
     {
+        public override string GetStringJoinSelector(string result, string separator)
+        {
+            return $"group_concat({result},'{separator},') ";
+        }
         public override string DateDiff(MethodCallExpressionModel model)
         {
             var parameter = (DateType)(Enum.Parse(typeof(DateType), model.Args[0].MemberValue.ObjToString()));

Src/Asp.Net/SqlSugar/SqlSugar.csproj

@@ -126,6 +126,7 @@
     <Compile Include="Entities\DbFastestProperties.cs" />
     <Compile Include="Entities\DeleteNavOptions.cs" />
     <Compile Include="ExpressionsToSql\Common\NewExpressionInfo.cs" />
+    <Compile Include="ExpressionsToSql\Subquery\Items\SubSelectStringJoin.cs" />
     <Compile Include="ExpressionsToSql\Subquery\Items\SubWithNoLock.cs" />
     <Compile Include="ExpressionsToSql\Subquery\Items\SubEnableTableFilter.cs" />
     <Compile Include="Json2Sql\Entities\JsonDeleteResult.cs" />