diff --git a/source/dnode/vnode/src/tsdb/dev/dev.h b/source/dnode/vnode/src/tsdb/dev/dev.h
index dec43b2a9a..401618f980 100644
--- a/source/dnode/vnode/src/tsdb/dev/dev.h
+++ b/source/dnode/vnode/src/tsdb/dev/dev.h
@@ -26,6 +26,8 @@ extern "C" {
 
 #include "tsdbFile.h"
 
+#include "tsdbFileOp.h"
+
 #include "tsdbFS.h"
 
 #include "tsdbSttFWriter.h"
diff --git a/source/dnode/vnode/src/tsdb/dev/tsdbCommit.c b/source/dnode/vnode/src/tsdb/dev/tsdbCommit.c
index d73174eba8..28b7a6276a 100644
--- a/source/dnode/vnode/src/tsdb/dev/tsdbCommit.c
+++ b/source/dnode/vnode/src/tsdb/dev/tsdbCommit.c
@@ -33,6 +33,7 @@ typedef struct {
   TSKEY   minKey;
   TSKEY   maxKey;
   // writer
+  SArray             *aFileOp;
   struct SSttFWriter *pWriter;
 } SCommitter;
 
@@ -358,7 +359,7 @@ _exit:
   return code;
 }
 
-int32_t tsdbCommitRollback(STsdb *pTsdb) {
+int32_t tsdbCommitAbort(STsdb *pTsdb) {
   int32_t code = 0;
   int32_t lino = 0;
 
diff --git a/source/dnode/vnode/src/tsdb/dev/tsdbFile.c b/source/dnode/vnode/src/tsdb/dev/tsdbFile.c
index d95c61a3cc..5306d2bcd6 100644
--- a/source/dnode/vnode/src/tsdb/dev/tsdbFile.c
+++ b/source/dnode/vnode/src/tsdb/dev/tsdbFile.c
@@ -15,15 +15,6 @@
 
 #include "dev.h"
 
-typedef enum {
-  TSDB_FOP_CREATE = -2,  // create a file
-  TSDB_FOP_EXTEND,       // extend a file
-  TSDB_FOP_NONE,         // no operation
-  TSDB_FOP_TRUNCATE,     // truncate a file
-  TSDB_FOP_DELETE,       // delete a file
-  TSDB_FOP_MAX,
-} tsdb_fop_t;
-
 const char *tsdb_ftype_suffix[] = {
     ".head",  // TSDB_FTYPE_HEAD
     ".data",  // TSDB_FTYPE_DATA
@@ -33,14 +24,6 @@ const char *tsdb_ftype_suffix[] = {
     ".stt",
 };
 
-struct SFileOp {
-  tsdb_fop_t op;
-  union {
-    struct {
-    } create;
-  };
-};
-
 int32_t tsdbTFileInit(STsdb *pTsdb, struct STFile *pFile) {
   SVnode *pVnode = pTsdb->pVnode;
   STfs   *pTfs = pVnode->pTfs;
diff --git a/source/dnode/vnode/src/tsdb/dev/tsdbFileOp.h b/source/dnode/vnode/src/tsdb/dev/tsdbFileOp.h
new file mode 100644
index 0000000000..30ea8b6aca
--- /dev/null
+++ b/source/dnode/vnode/src/tsdb/dev/tsdbFileOp.h
@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
+ *
+ * This program is free software: you can use, redistribute, and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3
+ * or later ("AGPL"), as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _TSDB_FILE_OP_H
+#define _TSDB_FILE_OP_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Exposed Handle */
+typedef enum {
+  TSDB_FOP_EXTEND = -2,
+  TSDB_FOP_CREATE,
+  TSDB_FOP_NONE,
+  TSDB_FOP_DELETE,
+  TSDB_FOP_TRUNCATE,
+} EFileOpType;
+
+struct SFileOp {
+  EFileOpType op;
+  // TODO
+};
+
+/* Exposed APIs */
+
+/* Exposed Structs */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /*_TSDB_FILE_OP_H*/
\ No newline at end of file
diff --git a/source/dnode/vnode/src/tsdb/dev/tsdbMerge.c b/source/dnode/vnode/src/tsdb/dev/tsdbMerge.c
new file mode 100644
index 0000000000..2c548fe8b8
--- /dev/null
+++ b/source/dnode/vnode/src/tsdb/dev/tsdbMerge.c
@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
+ *
+ * This program is free software: you can use, redistribute, and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3
+ * or later ("AGPL"), as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "dev.h"
+
+typedef struct {
+  STsdb *pTsdb;
+} SMerger;
+
+int32_t tsdbMergeBegin(STsdb *pTsdb) {
+  int32_t code = 0;
+  // TODO
+  return code;
+}
+
+int32_t tsdbMergeCommit(STsdb *pTsdb) {
+  int32_t code = 0;
+  // TODO
+  return code;
+}
+
+int32_t tsdbMergeAbort(STsdb *pTsdb) {
+  int32_t code = 0;
+  // TODO
+  return code;
+}
\ No newline at end of file