From 1299733477031c12460a2ce3c05f8c71f727010d Mon Sep 17 00:00:00 2001
From: bill <sunyinqi0508@gmail.com>
Date: Wed, 21 Sep 2022 04:42:04 +0800
Subject: [PATCH] bug fix on select distinct

---
 server/hasher.h | 51 +++++++++++++++++++++++++++++--------------------
 server/table.h  | 13 ++++++++-----
 2 files changed, 38 insertions(+), 26 deletions(-)

diff --git a/server/hasher.h b/server/hasher.h
index 2de5555..526c168 100644
--- a/server/hasher.h
+++ b/server/hasher.h
@@ -17,19 +17,46 @@ inline size_t append_bytes(const unsigned char* _First) noexcept {
 	return _Val;
 }
 
+inline size_t append_bytes(const astring_view& view) noexcept {
+	return append_bytes(view.str);
+}
+
+
+template <class ...Types>
+struct hasher {
+	template <size_t i = 0> typename std::enable_if< i == sizeof...(Types),
+		size_t>::type hashi(const std::tuple<Types...>&) const {
+		return 534235245539ULL;
+	}
+
+	template <size_t i = 0> typename std::enable_if < i < sizeof ...(Types),
+		size_t>::type hashi(const std::tuple<Types...>& record) const {
+		using current_type = typename std::decay<typename std::tuple_element<i, std::tuple<Types...>>::type>::type;
+
+		return std::hash<current_type>()(std::get<i>(record)) ^ hashi<i + 1>(record);
+	}
+	size_t operator()(const std::tuple<Types...>& record) const {
+		return hashi(record);
+	}
+};
+
+
 namespace std{
+
 	template<>
 	struct hash<astring_view> {
 		size_t operator()(const astring_view& _Keyval) const noexcept {
 			return append_bytes(_Keyval.str);
 		}
 	};
+
 	template<>
 	struct hash<types::date_t> {
 		size_t operator() (const types::date_t& _Keyval) const noexcept {
 			return std::hash<unsigned int>()(*(unsigned int*)(&_Keyval));
 		}
 	};
+
 	template<>
 	struct hash<types::time_t> {
 		size_t operator() (const types::time_t& _Keyval) const noexcept {
@@ -40,6 +67,7 @@ namespace std{
 			;
 		}
 	};
+
 	template<>
 	struct hash<types::timestamp_t>{
 		size_t operator() (const types::timestamp_t& _Keyval) const noexcept {
@@ -48,27 +76,8 @@ namespace std{
 		}
 	};
 
-}
+	template <class ...Types>
+	struct hash<std::tuple<Types...>> : public hasher<Types...>{ };
 
-inline size_t append_bytes(const astring_view& view) noexcept {
-	return append_bytes(view.str);
 }
 
-
-template <class ...Types>
-struct hasher {
-	template <size_t i = 0> typename std::enable_if< i == sizeof...(Types), 
-		size_t>::type hashi(const std::tuple<Types...>& record) const {
-		return 534235245539ULL;
-	}
-
-	template <size_t i = 0> typename std::enable_if< i < sizeof ...(Types), 
-		size_t>::type hashi(const std::tuple<Types...>& record) const {
-		using current_type = typename std::decay<typename std::tuple_element<i, std::tuple<Types...>>::type>::type;
-		
-		return std::hash<current_type>()(std::get<i>(record)) ^ hashi<i+1>(record);
-	}
-	size_t operator()(const std::tuple<Types...>& record) const {
-		return hashi(record);
-	}
-};
diff --git a/server/table.h b/server/table.h
index f96c0e6..eab5f9d 100644
--- a/server/table.h
+++ b/server/table.h
@@ -9,6 +9,8 @@
 #include <string>
 #include <algorithm>
 #include "io.h"
+#include "hasher.h"
+
 #undef ERROR
 template <typename T>
 class vector_type;
@@ -432,21 +434,21 @@ struct TableInfo {
 	void inline
 	reserve(std::index_sequence<Is...>, uint32_t size) {
 		const auto& assign_sz = [&size](auto& col){ col.size = size;};
-		(assign_sz(get_col<Is>(*this)), ...);
+		(assign_sz(get_col<Is>()), ...);
 	}
 	template <size_t ...Is> 
 	decltype(auto) inline 
 	get_record(std::index_sequence<Is...>, uint32_t i) {
-		return std::forward_as_tuple((get_col<Is>(*this)[i], ...));
+		return std::forward_as_tuple(get_col<Is>()[i] ...);
 	}
 	template <size_t ...Is> 
 	void inline 
-	set_record(std::index_sequence<Is...>, tuple_type t) {
+	set_record(std::index_sequence<Is...>, const tuple_type& t, uint32_t i) {
 		const auto& assign_field = 
 			[](auto& l, const auto& r){
 				l = r;
 			};
-		(assign_field(get_col<Is>(*this)[Is], std::get<Is>(t)), ...);
+		(assign_field(get_col<Is>()[i], std::get<Is>(t)), ...);
 	}
 	TableInfo<Types ...>* distinct() {
 		std::unordered_set<tuple_type> d_records;
@@ -456,8 +458,9 @@ struct TableInfo {
 			d_records.insert(get_record(seq, j));
 		}
 		reserve(seq, d_records.size());
+		uint32_t i = 0;
 		for (const auto& dr : d_records) {
-			set_record(seq, dr);
+			set_record(seq, dr, i++);
 		}
 		return this;
 	}