diff --git a/src/entry/Maat_ex_data.cpp b/src/entry/Maat_ex_data.cpp
index e78acea..7cf2a77 100644
--- a/src/entry/Maat_ex_data.cpp
+++ b/src/entry/Maat_ex_data.cpp
@@ -135,13 +135,14 @@ int EX_data_rt_row2EX_data(struct EX_data_rt* ex_rt,
 		return -1;
 	}
 	ex_container=ALLOC(struct EX_data_container, 1);
-	ex_schema->new_func(ex_rt->table_id, key, row, &ex_data, 
+	ex_container->key=ALLOC(char, key_len+1);
+	memcpy(ex_container->key, key, key_len);
+	ex_schema->new_func(ex_rt->table_id, ex_container->key, row, &ex_data, 
 						ex_schema->argl, ex_schema->argp);
 	ex_container->ex_data=ex_data;
 	ex_container->rt=ex_rt;
 	ex_container->user_data=user_data;
-	ex_container->key=ALLOC(char, key_len);
-	memcpy(ex_container->key, key, key_len);
+
 	ex_container->key_len=key_len;
 	HASH_ADD_KEYPTR(hh, ex_rt->hash_key2ex, ex_container->key, ex_container->key_len, ex_container);
 	return 0;
diff --git a/src/entry/Maat_rule.cpp b/src/entry/Maat_rule.cpp
index ad029f1..fac6b42 100644
--- a/src/entry/Maat_rule.cpp
+++ b/src/entry/Maat_rule.cpp
@@ -34,7 +34,7 @@
 #include "stream_fuzzy_hash.h"
 #include "gram_index_engine.h"
 
-int MAAT_FRAME_VERSION_3_0_20200706=1;
+int MAAT_FRAME_VERSION_3_0_20200707=1;
 
 int is_valid_table_name(const char* str)
 {
diff --git a/src/inc_internal/Maat_rule_internal.h b/src/inc_internal/Maat_rule_internal.h
index df61050..d151fc8 100644
--- a/src/inc_internal/Maat_rule_internal.h
+++ b/src/inc_internal/Maat_rule_internal.h
@@ -147,8 +147,8 @@ struct Maat_region_inner
 	int district_id;
 	int table_id;
 	int expr_id_cnt;
-	int expr_id_lb;
-	int expr_id_ub;
+	int expr_id_lb;	//low boundary
+	int expr_id_ub;	//up boundary
 	enum MAAT_TABLE_TYPE table_type;
 };