diff --git a/table/plain_table_key_coding.cc b/table/plain_table_key_coding.cc
index eedf58aea..dbe53c0c6 100644
--- a/table/plain_table_key_coding.cc
+++ b/table/plain_table_key_coding.cc
@@ -97,9 +97,9 @@ Status PlainTableKeyEncoder::AppendKey(const Slice& key, WritableFile* file,
 
     Slice prefix =
         prefix_extractor_->Transform(Slice(key.data(), user_key_size));
-    if (key_count_for_prefix == 0 || prefix != pre_prefix_.GetKey() ||
-        key_count_for_prefix % index_sparseness_ == 0) {
-      key_count_for_prefix = 1;
+    if (key_count_for_prefix_ == 0 || prefix != pre_prefix_.GetKey() ||
+        key_count_for_prefix_ % index_sparseness_ == 0) {
+      key_count_for_prefix_ = 1;
       pre_prefix_.SetKey(prefix);
       size_bytes_pos += EncodeSize(kFullKey, user_key_size, size_bytes);
       Status s = file->Append(Slice(size_bytes, size_bytes_pos));
@@ -108,8 +108,8 @@ Status PlainTableKeyEncoder::AppendKey(const Slice& key, WritableFile* file,
       }
       *offset += size_bytes_pos;
     } else {
-      key_count_for_prefix++;
-      if (key_count_for_prefix == 2) {
+      key_count_for_prefix_++;
+      if (key_count_for_prefix_ == 2) {
         // For second key within a prefix, need to encode prefix length
         size_bytes_pos +=
             EncodeSize(kPrefixFromPreviousKey, pre_prefix_.GetKey().size(),
diff --git a/table/plain_table_key_coding.h b/table/plain_table_key_coding.h
index ba66c2645..9047087ae 100644
--- a/table/plain_table_key_coding.h
+++ b/table/plain_table_key_coding.h
@@ -26,7 +26,7 @@ class PlainTableKeyEncoder {
         fixed_user_key_len_(user_key_len),
         prefix_extractor_(prefix_extractor),
         index_sparseness_((index_sparseness > 1) ? index_sparseness : 1),
-        key_count_for_prefix(0) {}
+        key_count_for_prefix_(0) {}
   // key: the key to write out, in the format of internal key.
   // file: the output file to write out
   // offset: offset in the file. Needs to be updated after appending bytes
@@ -45,7 +45,7 @@ class PlainTableKeyEncoder {
   uint32_t fixed_user_key_len_;
   const SliceTransform* prefix_extractor_;
   const size_t index_sparseness_;
-  size_t key_count_for_prefix;
+  size_t key_count_for_prefix_;
   IterKey pre_prefix_;
 };