diff --git a/source/libs/tdb/src/db/btree.c b/source/libs/tdb/src/db/btree.c
index 7d42484488..845bddc8b5 100644
--- a/source/libs/tdb/src/db/btree.c
+++ b/source/libs/tdb/src/db/btree.c
@@ -16,7 +16,7 @@
 #include "tdbInt.h"
 
 struct SBTree {
-  pgno_t rootPage;
+  pgno_t root;
   // TODO
 };
 
diff --git a/source/libs/tdb/src/db/pgcache.c b/source/libs/tdb/src/db/pgcache.c
index 8fb54c8344..7ca4f4239d 100644
--- a/source/libs/tdb/src/db/pgcache.c
+++ b/source/libs/tdb/src/db/pgcache.c
@@ -125,13 +125,19 @@ int pgCacheClose(SPgCache *pPgCache) {
   return 0;
 }
 
+#define PG_CACHE_HASH(fileid, pgno)       \
+  ({                                      \
+    uint64_t *tmp = (uint64_t *)(fileid); \
+    (tmp[0] + tmp[1] + tmp[2] + (pgno));  \
+  })
+
 SPage *pgCacheFetch(SPgCache *pPgCache, pgid_t pgid) {
   SPage *  pPage;
   SPgFile *pPgFile;
   SPgList *pBucket;
 
   // 1. Search the page hash table SPgCache.pght
-  pBucket = pPgCache->pght.buckets + ((0 /*TODO*/) % pPgCache->pght.nbucket);
+  pBucket = pPgCache->pght.buckets + (PG_CACHE_HASH(pgid.fileid, pgid.pgno) % pPgCache->pght.nbucket);
   pPage = TD_DLIST_HEAD(pBucket);
   while (pPage && tdbCmprPgId(&(pPage->pgid), &pgid)) {
     pPage = TD_DLIST_NODE_NEXT_WITH_FIELD(pPage, pghtNode);
diff --git a/source/libs/tdb/src/db/pgfile.c b/source/libs/tdb/src/db/pgfile.c
index 15c18b2950..2de0dd9cc5 100644
--- a/source/libs/tdb/src/db/pgfile.c
+++ b/source/libs/tdb/src/db/pgfile.c
@@ -76,7 +76,11 @@ SPage *pgFileFetch(SPgFile *pPgFile, pgno_t pgno) {
   memcpy(pgid.fileid, pPgFile->fileid, TDB_FILE_ID_LEN);
   pgid.pgno = pgno;
 
-  pPage = pgCacheFetch(pPgCache, pgid);
+  if (pgno > pPgFile->pgFileSize) {
+    // TODO
+  } else {
+    pPage = pgCacheFetch(pPgCache, pgid);
+  }
 
   return pPage;
 }
diff --git a/source/libs/tdb/src/db/tdb.c b/source/libs/tdb/src/db/tdb.c
index 0a24331a36..e75c6da00b 100644
--- a/source/libs/tdb/src/db/tdb.c
+++ b/source/libs/tdb/src/db/tdb.c
@@ -15,59 +15,7 @@
 
 #include "tdbInt.h"
 
-// static int tdbOpenImpl(TDB *dbp);
-
-// int tdbOpen(TDB **dbpp, const char *fname, const char *dbname, uint32_t flags) {
-//   TDB *       dbp;
-//   TDB_MPFILE *mpf;
-//   uint8_t     fileid[TDB_FILE_ID_LEN];
-
-//   if ((dbp = (TDB *)calloc(1, sizeof(*dbp))) == NULL) {
-//     return -1;
-//   }
-
-//   if ((dbp->fname = strdup(fname)) == NULL) {
-//     free(dbp);
-//     return -1;
-//   }
-
-//   if ((dbname) && ((dbp->dbname = strdup(dbname)) == NULL)) {
-//     free(dbp->fname);
-//     free(dbp);
-//     return -1;
-//   }
-
-//   // if (tdbGnrtFileID(fname, fileid) < 0) {
-//   //   // todo
-//   //   return -1;
-//   // }
-
-//   // TODO: mpf = tdbGetMPFileByID(fileid);
-//   if (mpf == NULL) {
-//     // todoerr: maybe we need to create one
-//     return -1;
-//   }
-
-//   if (tdbOpenImpl(dbp) < 0) {
-//     // todoerr
-//     return -1;
-//   }
-
-//   *dbpp = dbp;
-//   return 0;
-// }
-
-// int tdbClose(TDB *dbp, uint32_t flags) {
-//   // TODO
-//   return 0;
-// }
-
-// static int tdbOpenImpl(TDB *dbp) {
-//   if (dbp->dbname == NULL) {
-//     // todo: open the DB as a master DB
-//   } else {
-//     // todo: open the DB as a sub-db
-//   }
-//   // TODO
-//   return 0;
-// }
\ No newline at end of file
+struct STDb {
+  // TODO
+  SBTree *pBt;
+};
diff --git a/source/libs/tdb/src/inc/btree.h b/source/libs/tdb/src/inc/btree.h
index 757525d6a7..de143fa3a5 100644
--- a/source/libs/tdb/src/inc/btree.h
+++ b/source/libs/tdb/src/inc/btree.h
@@ -23,6 +23,12 @@ extern "C" {
 typedef struct SBTree    SBTree;
 typedef struct SBtCursor SBtCursor;
 
+// SBTree
+int btreeOpen(SBTree **ppBt);
+int btreeClose(SBTree *pBt);
+
+// SBtCursor
+
 #ifdef __cplusplus
 }
 #endif