diff --git a/rds_mysql/stored_procedure/crm_history.sql b/rds_mysql/stored_procedure/crm_history.sql
index 7573bf9b..b60e2681 100644
--- a/rds_mysql/stored_procedure/crm_history.sql
+++ b/rds_mysql/stored_procedure/crm_history.sql
@@ -1,5 +1,6 @@
 -- A5M2で実行時にSQL区切り文字を「;」以外にすること
--- $$から始まる文字は後からREPLACEする文字を示す独自ルール
+-- $$から始まり$$で終わる文字は後からREPLACEする文字を示す独自ルール
+-- crm_historyストアドプロシージャは、同一セッション内での並列処理を実行することができない
 CREATE PROCEDURE crm_history(target_table VARCHAR(255), target_column VARCHAR(255))
 BEGIN
 	-- 例外処理
@@ -15,21 +16,22 @@ BEGIN
 				SET MYSQL_ERRNO = @error_state, MESSAGE_TEXT = @error_msg;
 		END;
 
+	SET @error_state = NULL, @error_msg = NULL;
 	START TRANSACTION;
 
 	-- ②-3で利用する一時テーブル削除のSQLを準備
 	-- 例外処理でも利用するため先に記述
 	SET @drop_tmp_table = '
-		DROP TEMPORARY TABLE IF EXISTS $$target_table_make_history_tmp
+		DROP TEMPORARY TABLE IF EXISTS $$target_table$$_make_history_tmp
 	';
-	SET @drop_tmp_table = REPLACE(@drop_tmp_table, "$$target_table", target_table);
+	SET @drop_tmp_table = REPLACE(@drop_tmp_table, "$$target_table$$", target_table);
 	PREPARE drop_tmp_table_stmt from @drop_tmp_table;
 	
 	-- ①-1 Salesforce側で更新されたデータの適用開始日時と適用終了日時を設定する
 	SET @new_history_save = '
-		UPDATE $$target_table 
+		UPDATE $$target_table$$ 
 		SET
-			start_datetime = $$target_column
+			start_datetime = $$target_column$$
 			, end_datetime = "9999-12-31 00:00:00"
 			, upd_user = CURRENT_USER() 
 			, upd_date = CURRENT_TIMESTAMP()
@@ -37,21 +39,21 @@ BEGIN
 			start_datetime IS NULL 
 			AND end_datetime IS NULL
 	';
-	SET @new_history_save = REPLACE(@new_history_save, "$$target_table", target_table);
-	SET @new_history_save = REPLACE(@new_history_save, "$$target_column", target_column);
+	SET @new_history_save = REPLACE(@new_history_save, "$$target_table$$", target_table);
+	SET @new_history_save = REPLACE(@new_history_save, "$$target_column$$", target_column);
 	PREPARE new_history_save_stmt from @new_history_save;
 	EXECUTE new_history_save_stmt;
 	DEALLOCATE PREPARE new_history_save_stmt;
 
 	-- ②-1 Salesforce側で更新されたデータを検出用一時テーブルの作成
 	SET @make_history_tmp_create = '
-		CREATE TEMPORARY TABLE $$target_table_make_history_tmp 
+		CREATE TEMPORARY TABLE $$target_table$$_make_history_tmp 
 		SELECT
 			id
-			, MIN($$target_column) AS min_start_datetime
+			, MIN($$target_column$$) AS min_start_datetime
 			, MAX(start_datetime) AS max_start_datetime 
 		FROM
-			$$target_table 
+			$$target_table$$ 
 		WHERE
 			end_datetime = "9999-12-31 00:00:00" 
 		GROUP BY
@@ -59,16 +61,16 @@ BEGIN
 		HAVING
 			count(id) = 2
 	';
-	SET @make_history_tmp_create = REPLACE(@make_history_tmp_create, "$$target_table", target_table);
-	SET @make_history_tmp_create = REPLACE(@make_history_tmp_create, "$$target_column", target_column);
+	SET @make_history_tmp_create = REPLACE(@make_history_tmp_create, "$$target_table$$", target_table);
+	SET @make_history_tmp_create = REPLACE(@make_history_tmp_create, "$$target_column$$", target_column);
 	PREPARE make_history_tmp_create_stmt from @make_history_tmp_create;
 	EXECUTE make_history_tmp_create_stmt;
 	DEALLOCATE PREPARE make_history_tmp_create_stmt;
 
 	-- ②-2 「②-1」で取得した全件に更新処理を行う
 	SET @update_end_datetime = '
-		UPDATE $$target_table tt 
-			LEFT JOIN $$target_table_make_history_tmp mht 
+		UPDATE $$target_table$$ tt 
+			LEFT JOIN $$target_table$$_make_history_tmp mht 
 				ON tt.id = mht.id 
 				AND tt.start_datetime = mht.min_start_datetime 
 		SET
@@ -78,8 +80,8 @@ BEGIN
 		WHERE
 			mht.id IS NOT NULL
 	';
-	SET @update_end_datetime = REPLACE(@update_end_datetime, "$$target_table", target_table);
-	SET @update_end_datetime = REPLACE(@update_end_datetime, "$$target_column", target_column);
+	SET @update_end_datetime = REPLACE(@update_end_datetime, "$$target_table$$", target_table);
+	SET @update_end_datetime = REPLACE(@update_end_datetime, "$$target_column$$", target_column);
 	PREPARE update_end_datetime_stmt from @update_end_datetime;
 	EXECUTE update_end_datetime_stmt;
 	DEALLOCATE PREPARE update_end_datetime_stmt;