Fix database bindings

Author: ls4154

lmdb/lmdb_db.cc

@@ -235,9 +235,8 @@ DB::Status LmdbDB::Scan(const std::string &table, const std::string &key, int le
   if (ret) {
     throw utils::Exception(std::string("Scan mdb_cursor_open: ") + mdb_strerror(ret));
   }
-  ret = mdb_cursor_get(cursor, &key_slice, &val_slice, MDB_SET);
+  ret = mdb_cursor_get(cursor, &key_slice, &val_slice, MDB_SET_RANGE);
   if (ret == MDB_NOTFOUND) {
-    s = kNotFound;
     goto cleanup;
   } else if (ret) {
     throw utils::Exception(std::string("Scan mdb_cursor_get: ") + mdb_strerror(ret));

sqlite/sqlite_db.cc

@@ -282,10 +282,6 @@ DB::Status SqliteDB::Scan(const std::string &table, const std::string &key, int
     }
   }
 
-  if (result.size() == 0) {
-    s = kNotFound;
-  }
-
 cleanup:
   sqlite3_reset(stmt);
   sqlite3_clear_bindings(stmt);

wiredtiger/wiredtiger_db.cc

@@ -234,9 +234,17 @@ DB::Status WTDB::ScanSingleEntry(const std::string &table, const std::string &ke
   int ret = 0, exact;
 
   cursor_->set_key(cursor_, &k);
-  error_check(cursor_->search_near(cursor_, &exact));
+  ret = cursor_->search_near(cursor_, &exact);
+  if (ret == WT_NOTFOUND) {
+    return kOK;
+  }
+  error_check(ret);
   if (exact < 0) {
     ret = cursor_->next(cursor_);
+    if (ret == WT_NOTFOUND) {
+      return kOK;
+    }
+    error_check(ret);
   }
   for(int i=0; !ret && i<len; ++i){
     error_check(cursor_->get_value(cursor_, &v));
@@ -246,6 +254,10 @@ DB::Status WTDB::ScanSingleEntry(const std::string &table, const std::string &ke
     } else {
       DeserializeRow(&result.back(), (const char*)v.data, v.size);
     }
+    ret = cursor_->next(cursor_);
+    if (ret != 0 && ret != WT_NOTFOUND) {
+      error_check(ret);
+    }
   }
   return kOK;
 }

wiredtiger/wiredtiger_db.h

@@ -85,7 +85,7 @@ class WTDB : public DB {
 
 };
 
-DB *NewRocksdbDB();
+DB *NewWTDB();
 
 } // namespace ycsbc