diff --git a/Makefile b/Makefile
index dcdf17c..2efdb7c 100644
--- a/Makefile
+++ b/Makefile
@@ -10,7 +10,8 @@ EXTENSION = pg_store_plans
 
 PG_VERSION := $(shell pg_config --version | sed "s/^PostgreSQL //" | sed "s/\.[0-9]*$$//")
 
-DATA = pg_store_plans--1.9.sql
+DATA = pg_store_plans--1.9.sql \
+	   pg_store_plans--1.8--1.9.sql
 
 REGRESS = convert store
 REGRESS_OPTS = --temp-config=regress.conf
diff --git a/pg_store_plans--1.8--1.9.sql b/pg_store_plans--1.8--1.9.sql
new file mode 100644
index 0000000..4ac802b
--- /dev/null
+++ b/pg_store_plans--1.8--1.9.sql
@@ -0,0 +1,105 @@
+/*
+ * pg_store_plans/pg_store_plans--1.8--1.9.sql
+ *
+ * 업그레이드 스크립트: pg_store_plans 1.8 -> 1.9
+ *
+ * - 기존 함수 및 뷰 삭제
+ * - PostgreSQL 17 이상/미만 버전별 함수(분기 처리) 재생성
+ * - 뷰 생성 및 권한 부여
+ */
+
+-- psql에서 직접 실행되는 것을 방지 (CREATE EXTENSION을 통해서만 실행)
+\echo Use "CREATE EXTENSION pg_store_plans" to load this file. \quit
+
+-- 기존 뷰 및 함수 삭제 (업그레이드 전 정리)
+DROP VIEW pg_store_plans;
+DROP FUNCTION pg_store_plans();
+
+-- PostgreSQL 버전에 따라 메인 함수 생성 (17 이상/미만 분기)
+DO
+$$
+BEGIN
+    IF (SELECT split_part(setting,'.',1) FROM pg_settings WHERE name = 'server_version')::int >= 17 THEN
+        -- PostgreSQL 17 이상: shared/local 블록 시간 컬럼 분리
+        CREATE FUNCTION pg_store_plans(
+            OUT userid oid,
+            OUT dbid oid,
+            OUT queryid int8,
+            OUT planid int8,
+            OUT plan text,
+            OUT calls int8,
+            OUT total_time float8,
+            OUT min_time float8,
+            OUT max_time float8,
+            OUT mean_time float8,
+            OUT stddev_time float8,
+            OUT rows int8,
+            OUT shared_blks_hit int8,
+            OUT shared_blks_read int8,
+            OUT shared_blks_dirtied int8,
+            OUT shared_blks_written int8,
+            OUT local_blks_hit int8,
+            OUT local_blks_read int8,
+            OUT local_blks_dirtied int8,
+            OUT local_blks_written int8,
+            OUT temp_blks_read int8,
+            OUT temp_blks_written int8,
+            OUT shared_blk_read_time float8,
+            OUT shared_blk_write_time float8,
+            OUT local_blk_read_time float8,
+            OUT local_blk_write_time float8,
+            OUT temp_blk_read_time float8,
+            OUT temp_blk_write_time float8,
+            OUT first_call timestamptz,
+            OUT last_call timestamptz
+        )
+        RETURNS SETOF record
+        AS 'MODULE_PATHNAME', 'pg_store_plans_1_9'
+        LANGUAGE C
+        VOLATILE PARALLEL SAFE;
+    ELSE
+        -- PostgreSQL 17 미만: blk_read_time, blk_write_time 사용
+        CREATE FUNCTION pg_store_plans(
+            OUT userid oid,
+            OUT dbid oid,
+            OUT queryid int8,
+            OUT planid int8,
+            OUT plan text,
+            OUT calls int8,
+            OUT total_time float8,
+            OUT min_time float8,
+            OUT max_time float8,
+            OUT mean_time float8,
+            OUT stddev_time float8,
+            OUT rows int8,
+            OUT shared_blks_hit int8,
+            OUT shared_blks_read int8,
+            OUT shared_blks_dirtied int8,
+            OUT shared_blks_written int8,
+            OUT local_blks_hit int8,
+            OUT local_blks_read int8,
+            OUT local_blks_dirtied int8,
+            OUT local_blks_written int8,
+            OUT temp_blks_read int8,
+            OUT temp_blks_written int8,
+            OUT blk_read_time float8,
+            OUT blk_write_time float8,
+            OUT temp_blk_read_time float8,
+            OUT temp_blk_write_time float8,
+            OUT first_call timestamptz,
+            OUT last_call timestamptz
+        )
+        RETURNS SETOF record
+        AS 'MODULE_PATHNAME', 'pg_store_plans_1_7'
+        LANGUAGE C
+        VOLATILE PARALLEL SAFE;
+    END IF;
+END
+$$ LANGUAGE plpgsql;
+
+-- 메인 함수에 대한 뷰 생성 (사용 편의성 제공)
+CREATE VIEW pg_store_plans AS
+  SELECT * FROM pg_store_plans();
+
+-- 모든 사용자에게 SELECT 권한 부여
+GRANT SELECT ON pg_store_plans TO PUBLIC;
diff --git a/pg_store_plans--1.9.sql b/pg_store_plans--1.9.sql
index 9f2bec3..77971dd 100644
--- a/pg_store_plans--1.9.sql
+++ b/pg_store_plans--1.9.sql
@@ -1,9 +1,17 @@
-/* pg_store_plans/pg_store_plans--1.9.sql */
+/*
+ * pg_store_plans/pg_store_plans--1.9.sql
+ *
+ * 확장 설치용 SQL 스크립트 (버전 1.9)
+ *
+ * - 주요 함수 및 뷰 생성
+ * - PostgreSQL 17 이상/미만 버전별 함수(분기 처리) 생성
+ * - 권한 부여
+ */
 
--- complain if script is sourced in psql, rather than via CREATE EXTENSION
+-- psql에서 직접 실행되는 것을 방지 (CREATE EXTENSION을 통해서만 실행)
 \echo Use "CREATE EXTENSION pg_store_plans" to load this file. \quit
 
---- Define pg_store_plans_info
+--- pg_store_plans_info 함수 및 뷰 정의 (통계 정보 제공)
 CREATE FUNCTION pg_store_plans_info(
     OUT dealloc bigint,
     OUT stats_reset timestamp with time zone
@@ -17,7 +25,7 @@ CREATE VIEW pg_store_plans_info AS
 
 GRANT SELECT ON pg_store_plans_info TO PUBLIC;
 
--- Register functions.
+-- 주요 기능 함수 등록 (플랜 리셋, 쿼리 축약, 정규화, 다양한 포맷 변환 등)
 CREATE FUNCTION pg_store_plans_reset()
 RETURNS void
 AS 'MODULE_PATHNAME'
@@ -57,48 +65,95 @@ RETURNS oid
 AS 'MODULE_PATHNAME'
 LANGUAGE C
 RETURNS NULL ON NULL INPUT PARALLEL SAFE;
-CREATE FUNCTION pg_store_plans(
-    OUT userid oid,
-    OUT dbid oid,
-    OUT queryid int8,
-    OUT planid int8,
-    OUT plan text,
-    OUT calls int8,
-    OUT total_time float8,
-    OUT min_time float8,
-    OUT max_time float8,
-    OUT mean_time float8,
-    OUT stddev_time float8,
-    OUT rows int8,
-    OUT shared_blks_hit int8,
-    OUT shared_blks_read int8,
-    OUT shared_blks_dirtied int8,
-    OUT shared_blks_written int8,
-    OUT local_blks_hit int8,
-    OUT local_blks_read int8,
-    OUT local_blks_dirtied int8,
-    OUT local_blks_written int8,
-    OUT temp_blks_read int8,
-    OUT temp_blks_written int8,
-    OUT shared_blk_read_time float8,
-    OUT shared_blk_write_time float8,
-    OUT local_blk_read_time float8,
-    OUT local_blk_write_time float8,
-    OUT temp_blk_read_time float8,
-    OUT temp_blk_write_time float8,
-    OUT first_call timestamptz,
-    OUT last_call timestamptz
-)
-RETURNS SETOF record
-AS 'MODULE_PATHNAME', 'pg_store_plans_1_9'
-LANGUAGE C
-VOLATILE PARALLEL SAFE;
 
--- Register a view on the function for ease of use.
+-- PostgreSQL 버전에 따라 메인 함수 생성 (17 이상/미만 분기)
+DO
+$$
+BEGIN
+    IF (SELECT split_part(setting,'.',1) FROM pg_settings WHERE name = 'server_version')::int >= 17 THEN
+        -- PostgreSQL 17 이상: shared/local 블록 시간 컬럼 분리
+        CREATE FUNCTION pg_store_plans(
+            OUT userid oid,
+            OUT dbid oid,
+            OUT queryid int8,
+            OUT planid int8,
+            OUT plan text,
+            OUT calls int8,
+            OUT total_time float8,
+            OUT min_time float8,
+            OUT max_time float8,
+            OUT mean_time float8,
+            OUT stddev_time float8,
+            OUT rows int8,
+            OUT shared_blks_hit int8,
+            OUT shared_blks_read int8,
+            OUT shared_blks_dirtied int8,
+            OUT shared_blks_written int8,
+            OUT local_blks_hit int8,
+            OUT local_blks_read int8,
+            OUT local_blks_dirtied int8,
+            OUT local_blks_written int8,
+            OUT temp_blks_read int8,
+            OUT temp_blks_written int8,
+            OUT shared_blk_read_time float8,
+            OUT shared_blk_write_time float8,
+            OUT local_blk_read_time float8,
+            OUT local_blk_write_time float8,
+            OUT temp_blk_read_time float8,
+            OUT temp_blk_write_time float8,
+            OUT first_call timestamptz,
+            OUT last_call timestamptz
+        )
+        RETURNS SETOF record
+        AS 'MODULE_PATHNAME', 'pg_store_plans_1_9'
+        LANGUAGE C
+        VOLATILE PARALLEL SAFE;
+    ELSE
+        -- PostgreSQL 17 미만: blk_read_time, blk_write_time 사용
+        CREATE FUNCTION pg_store_plans(
+            OUT userid oid,
+            OUT dbid oid,
+            OUT queryid int8,
+            OUT planid int8,
+            OUT plan text,
+            OUT calls int8,
+            OUT total_time float8,
+            OUT min_time float8,
+            OUT max_time float8,
+            OUT mean_time float8,
+            OUT stddev_time float8,
+            OUT rows int8,
+            OUT shared_blks_hit int8,
+            OUT shared_blks_read int8,
+            OUT shared_blks_dirtied int8,
+            OUT shared_blks_written int8,
+            OUT local_blks_hit int8,
+            OUT local_blks_read int8,
+            OUT local_blks_dirtied int8,
+            OUT local_blks_written int8,
+            OUT temp_blks_read int8,
+            OUT temp_blks_written int8,
+            OUT blk_read_time float8,
+            OUT blk_write_time float8,
+            OUT temp_blk_read_time float8,
+            OUT temp_blk_write_time float8,
+            OUT first_call timestamptz,
+            OUT last_call timestamptz
+        )
+        RETURNS SETOF record
+        AS 'MODULE_PATHNAME', 'pg_store_plans_1_7'
+        LANGUAGE C
+        VOLATILE PARALLEL SAFE;
+    END IF;
+END
+$$ LANGUAGE plpgsql;
+
+-- 메인 함수에 대한 뷰 생성 (사용 편의성 제공)
 CREATE VIEW pg_store_plans AS
   SELECT * FROM pg_store_plans();
 
+-- 모든 사용자에게 SELECT 권한 부여
 GRANT SELECT ON pg_store_plans TO PUBLIC;
 
--- Don't want this to be available to non-superusers.
+-- superuser가 아닌 사용자에게는 리셋 함수 권한 제한
 REVOKE ALL ON FUNCTION pg_store_plans_reset() FROM PUBLIC;
diff --git a/pg_store_plans.c b/pg_store_plans.c
index 3b2e64b..eb19a9c 100644
--- a/pg_store_plans.c
+++ b/pg_store_plans.c
@@ -423,7 +423,7 @@ _PG_init(void)
 	  "Sets the maximum number of plans tracked by pg_store_plans.",
 							NULL,
 							&store_size,
-							1000,
+							5000,
 							100,
 							INT_MAX,
 							PGC_POSTMASTER,
@@ -485,7 +485,7 @@ _PG_init(void)
 					"Minimum duration to record plan in milliseconds.",
 							NULL,
 							&min_duration,
-							0,
+							10,
 							0,
 							INT_MAX,
 							PGC_SUSET,
@@ -531,7 +531,7 @@ _PG_init(void)
 							 "Log timings.",
 							 NULL,
 							 &log_timing,
-							 true,
+							 false,
 							 PGC_SUSET,
 							 0,
 							 NULL,
@@ -752,6 +752,15 @@ pgsp_shmem_startup(void)
 		pgver != PGSP_PG_MAJOR_VERSION)
 		goto data_error;
 
+	/* check if num is out of range */
+	if (num < 0 || num > store_size)
+	{
+	    ereport(LOG,
+		    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+		     errmsg("Invalid number of entries in file: %d", num)));
+	    goto data_error;
+	}
+
 	for (i = 0; i < num; i++)
 	{
 		pgspEntry	temp;
@@ -944,6 +953,10 @@ pgsp_shmem_shutdown(int code, Datum arg)
 	/* Unlink query-texts file; it's not needed while shutdown */
 	unlink(PGSP_TEXT_FILE);
 
+	if (pbuffer){
+		free(pbuffer);  // or free(pbuffer)
+		pbuffer = NULL;
+	}
 	return;
 
 error:
@@ -954,6 +967,10 @@ pgsp_shmem_shutdown(int code, Datum arg)
 	if (file)
 		FreeFile(file);
 	unlink(PGSP_DUMP_FILE ".tmp");
+	if (pbuffer){
+		free(pbuffer);  // or free(pbuffer)
+		pbuffer = NULL;
+	}
 }
 
 
@@ -1234,6 +1251,7 @@ pgsp_store(char *plan, queryid_t queryId,
 		return;
 
 	/* Set up key for hashtable search */
+	memset(&key, 0, sizeof(key));
 	key.userid = GetUserId();
 	key.dbid = MyDatabaseId;
 	key.queryid = queryId;
@@ -1612,6 +1630,9 @@ pg_store_plans_internal(FunctionCallInfo fcinfo,
 			else
 				pstr = SHMEM_PLAN_PTR(entry);
 
+			if (pstr == NULL)
+				continue;			/* Ignore any entries with bogus texts */
+
 			switch (plan_format)
 			{
 				case PLAN_FORMAT_TEXT:
@@ -1691,21 +1712,38 @@ pg_store_plans_internal(FunctionCallInfo fcinfo,
 		values[i++] = Int64GetDatumFast(tmp.local_blks_written);
 		values[i++] = Int64GetDatumFast(tmp.temp_blks_read);
 		values[i++] = Int64GetDatumFast(tmp.temp_blks_written);
-		values[i++] = Float8GetDatumFast(tmp.shared_blk_read_time);
-		values[i++] = Float8GetDatumFast(tmp.shared_blk_write_time);
 
 		if (api_version >= PGSP_V1_9)
 		{
 #if PG_VERSION_NUM >= 170000
+			values[i++] = Float8GetDatumFast(tmp.shared_blk_read_time);
+			values[i++] = Float8GetDatumFast(tmp.shared_blk_write_time);
 			values[i++] = Float8GetDatumFast(tmp.local_blk_read_time);
 			values[i++] = Float8GetDatumFast(tmp.local_blk_write_time);
 #else
 			values[i++] = Float8GetDatumFast(0.0);
 			values[i++] = Float8GetDatumFast(0.0);
+			values[i++] = Float8GetDatumFast(0.0);
+			values[i++] = Float8GetDatumFast(0.0);
 #endif
 		}
 		if (api_version >= PGSP_V1_7)
 		{
+#if PG_VERSION_NUM >= 170000
+			if (api_version < PGSP_V1_9)
+			{
+				values[i++] = Float8GetDatumFast(tmp.shared_blk_read_time+
+												 tmp.local_blk_read_time);
+				values[i++] = Float8GetDatumFast(tmp.shared_blk_write_time+
+												 tmp.local_blk_write_time);
+			}
+#else
+			if (api_version < PGSP_V1_9)
+			{
+				values[i++] = Float8GetDatumFast(tmp.blk_read_time);
+				values[i++] = Float8GetDatumFast(tmp.blk_write_time);
+			}
+#endif
 			values[i++] = Float8GetDatumFast(tmp.temp_blk_read_time);
 			values[i++] = Float8GetDatumFast(tmp.temp_blk_write_time);
 		}
@@ -1723,6 +1761,11 @@ pg_store_plans_internal(FunctionCallInfo fcinfo,
 	}
 
 	LWLockRelease(shared_state->lock);
+
+	if (pbuffer){
+		free(pbuffer);  // or free(pbuffer)
+		pbuffer = NULL;
+	}
 }
 
 /* Number of output arguments (columns) for pg_stat_statements_info */