From b67e8cf65890ab37feaa063d98e3b3c03da93947 Mon Sep 17 00:00:00 2001
From: SisMaker <1713699517@qq.com>
Date: Tue, 4 Jul 2023 23:22:31 +0800
Subject: [PATCH] =?UTF-8?q?ft:=20ets=E7=9B=B8=E5=85=B3?=
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---
 src/docs/erlang/etsmatch.hrl.md | 14 +++++++++++++-
 src/template/utEtsFold.erl      | 33 ++++++++++++++++++++++++++++++++-
 2 files changed, 45 insertions(+), 2 deletions(-)

diff --git a/src/docs/erlang/etsmatch.hrl.md b/src/docs/erlang/etsmatch.hrl.md
index 1ef15c3..3d46106 100644
--- a/src/docs/erlang/etsmatch.hrl.md
+++ b/src/docs/erlang/etsmatch.hrl.md
@@ -30,4 +30,16 @@ ets表并发写优化
             case Success of
             true -> New;
             false -> update_with_fun(Table, Key, Fun)
-        end.
\ No newline at end of file
+        end.
+
+match
+    用法：获取 ets 存储数据结构的某几个数据集合
+match_object
+    用法：获取 ets 存储的符合条件的整个结构，只能支持直接值匹配
+    用法 1：迭代的遍历整个 ets 列表 match_object/3
+    用法 2：查找指定数据的 ets 列表 match_object/2
+select
+    用法： 一般用于条件判定来筛选符合条件的数据和指定格式 (>=, =/=,<,=< 等)
+    一般和 ets:fun2ms 结合使用
+    效率较前两个较为慢一些，特别是 ets 中 key 的查找，效率就更慢了，能用 match_object 的就不要用 select
+
diff --git a/src/template/utEtsFold.erl b/src/template/utEtsFold.erl
index 5db6a71..d7aaf03 100644
--- a/src/template/utEtsFold.erl
+++ b/src/template/utEtsFold.erl
@@ -1,7 +1,9 @@
 -module(utEtsFold).
-
+-include_lib("stdlib/include/ms_transform.hrl").
 %% 请注意，对于表类型ordered_set和由单个 ETS 函数调用(如select/2)完成的遍历(一次调用就返回了全部结果没有Next 迭代器了)，不需要 safe_fixtable/ 2 。
 
+-compile([export_all]).
+
 -export([rank/5, fold/2]).
 
 rank(TabId, PageInfo, Page, Limit, TotalCnt) ->
@@ -89,3 +91,32 @@ continueNext(NextKey) ->
 matchDoFun(_ValueList) ->
    %% do something
    ok.
+
+new() ->
+   ets:new(test_replace, [named_table, public]),
+   [ets:insert(test_replace, {One, #{ One => One}}) || One <- lists:seq(1, 100000)],
+   ok.
+
+new_bag(Count) ->
+   ets:new(test_bag, [named_table, public, bag]),
+   [ets:insert(test_bag, {1, One}) || One <- lists:seq(1, Count)],
+   ok.
+
+replace(Key) ->
+   [{Key, Map}] = ets:lookup(test_replace, Key),
+   NewMap = Map#{aaa => aaa},
+   Ms = ets:fun2ms(fun({Key1, OldMap}) when Key =/= Key1 -> {Key1, 1} end),
+   ets:select_replace(test_replace, Ms).
+replace2(Key) ->
+   [{Key, Map} = Old] = ets:lookup(test_replace, Key),
+   NewMap = Map#{bbbb => bbb},
+   ets:select_replace(test_replace, [{Old, [], [{const, {Key, NewMap}}]}]).
+
+replace3(Key) ->
+   [{Key, Map} = Old] = ets:lookup(test_replace, Key),
+   NewMap = Map#{bbbb => bbb},
+   ets:select_replace(test_replace, [{Old, [], [{const, {Key, NewMap}}]}]).
+
+
+
+