diff --git a/storage/tianmu/compress/code_stream.h b/storage/tianmu/compress/code_stream.h
index a77c086ed..2ff1de7f7 100644
--- a/storage/tianmu/compress/code_stream.h
+++ b/storage/tianmu/compress/code_stream.h
@@ -34,10 +34,10 @@ class CoderStream : protected ArithCoder {
     my_stream_.Reset(buf, len, pos);
     str_ = &my_stream_;
   }
-  void Reset(BitStream *str_ = 0) { str_ = str_; }
+  void Reset(BitStream *str = 0) { str_ = str; }
   CoderStream() { Reset(); }
   CoderStream(char *buf, uint len, uint pos = 0) { Reset(buf, len, pos); }
-  CoderStream(BitStream *str_) { Reset(str_); }
+  CoderStream(BitStream *str) { Reset(str); }
   virtual ~CoderStream() {}
   using ArithCoder::BaseT;
   using ArithCoder::MAX_TOTAL_;
diff --git a/storage/tianmu/compress/data_stream.h b/storage/tianmu/compress/data_stream.h
index 841eaf529..0744de736 100644
--- a/storage/tianmu/compress/data_stream.h
+++ b/storage/tianmu/compress/data_stream.h
@@ -42,9 +42,9 @@ class DataStream {
   using uint64_t = unsigned long long;
 
   void Reset() { pos_ = 0; }
-  void Reset(uint len_, uint pos_ = 0) {
-    len_ = len_;
-    pos_ = pos_;
+  void Reset(uint len, uint pos = 0) {
+    len_ = len;
+    pos_ = pos;
   }
   void Reset(char *buf, uint len, uint pos = 0) {
     buf_ = (uchar *)buf;
@@ -57,7 +57,7 @@ class DataStream {
   virtual ~DataStream() {}
   char *GetBuf() { return (char *)buf_; }
   uint GetPos() { return pos_; }
-  void SetPos(uint pos_) { pos_ = pos_; }
+  void SetPos(uint pos) { pos_ = pos; }
   bool CanRead() { return pos_ < len_; }
   bool CanWrite() { return pos_ < len_; }
   virtual uchar Get() = 0;
@@ -85,18 +85,18 @@ class BitStream : public DataStream {
     DataStream::Reset();
     clrlen_ = 0;
   }
-  void Reset(uint len_, uint pos_ = 0) {
-    DataStream::Reset(len_, pos_);
+  void Reset(uint len, uint pos = 0) {
+    DataStream::Reset(len, pos);
     clrlen_ = 0;
   }
-  void Reset(char *buf_, uint len_, uint pos_ = 0) {
-    DataStream::Reset(buf_, len_, pos_);
+  void Reset(char *buf, uint len, uint pos = 0) {
+    DataStream::Reset(buf, len, pos);
     clrlen_ = 0;
   }
 
   // len_, pos_ - numbers of BITS
   BitStream() { Reset(0, 0, 0); }
-  BitStream(char *buf_, uint len_, uint pos_ = 0) { Reset(buf_, len_, pos_); }
+  BitStream(char *buf, uint len, uint pos = 0) { Reset(buf, len, pos); }
   virtual ~BitStream() {}
   uchar NextBit();              // show the next bit, but don't remove it from the stream
   uchar NextByte();             // show the next byte, but don't remove it from the stream
diff --git a/storage/tianmu/compress/ppm_defs.h b/storage/tianmu/compress/ppm_defs.h
index 1aa3f7a88..d712a319e 100644
--- a/storage/tianmu/compress/ppm_defs.h
+++ b/storage/tianmu/compress/ppm_defs.h
@@ -61,7 +61,7 @@ class PPMModel {
   static const int N_Symb_ = 256;
 
  public:
-  virtual void TransformForPPM(PPMParam param_ = PPMParam()) = 0;
+  virtual void TransformForPPM(PPMParam param = PPMParam()) = 0;
 
   virtual void InitPPM() = 0;
 
diff --git a/storage/tianmu/compress/suffix_tree.cpp b/storage/tianmu/compress/suffix_tree.cpp
index ef6b762b1..65d68b007 100644
--- a/storage/tianmu/compress/suffix_tree.cpp
+++ b/storage/tianmu/compress/suffix_tree.cpp
@@ -352,8 +352,8 @@ void SuffixTree<Symb, NSymb>::Print(std::ostream &str, uint flags, PNode n, PNod
 //------------------------------------------------------------------------
 
 template <class Symb, int NSymb>
-void SuffixTree<Symb, NSymb>::TransformForPPM(PPMParam param_) {
-  param_ = param_;
+void SuffixTree<Symb, NSymb>::TransformForPPM(PPMParam param) {
+  param_ = param;
 
   // compute counts of all nodes_ in the 'tree'
   SetCounts();
diff --git a/storage/tianmu/compress/suffix_tree.h b/storage/tianmu/compress/suffix_tree.h
index af5abcf4d..4480f7b07 100644
--- a/storage/tianmu/compress/suffix_tree.h
+++ b/storage/tianmu/compress/suffix_tree.h
@@ -306,7 +306,7 @@ class SuffixTree : public PPMModel {
   //-------------------------------------------------------------------------
   // definitions for PPM
 
-  void TransformForPPM(PPMParam param_ = PPMParam()) override;
+  void TransformForPPM(PPMParam param = PPMParam()) override;
   void InitPPM() override { state_ = ROOT_; }
   // compression: [str,len_total] -> [len_of_edge,rng,total]
   void Move(Symb *str, int &len, Range &rng, Count &total) override;
diff --git a/storage/tianmu/compress/word_graph.cpp b/storage/tianmu/compress/word_graph.cpp
index 0960425f4..5c5cb4857 100644
--- a/storage/tianmu/compress/word_graph.cpp
+++ b/storage/tianmu/compress/word_graph.cpp
@@ -377,8 +377,8 @@ void WordGraph::Print(std::ostream &str, [[maybe_unused]] uint flags) {
 // transformation for PPM
 //------------------------------------------------------------------------
 
-void WordGraph::TransformForPPM(PPMParam param_) {
-  param_ = param_;
+void WordGraph::TransformForPPM(PPMParam param) {
+  param_ = param;
 
   // propagate 'stop' numbers from final nodes_ to all border-path nodes_
   PropagateStop();
diff --git a/storage/tianmu/compress/word_graph.h b/storage/tianmu/compress/word_graph.h
index ca4b24a0e..78e4be6bf 100644
--- a/storage/tianmu/compress/word_graph.h
+++ b/storage/tianmu/compress/word_graph.h
@@ -252,7 +252,7 @@ class WordGraph : public PPMModel {
   //-------------------------------------------------------------------------
   // definitions for PPM
 
-  void TransformForPPM(PPMParam param_ = PPMParam()) override;
+  void TransformForPPM(PPMParam param = PPMParam()) override;
   void InitPPM() override;
 
   // compression: [str,len_total] -> [len_of_edge,rng,total]
diff --git a/storage/tianmu/types/rc_item_types.h b/storage/tianmu/types/rc_item_types.h
index 0a72f6cc7..6192e174a 100644
--- a/storage/tianmu/types/rc_item_types.h
+++ b/storage/tianmu/types/rc_item_types.h
@@ -47,7 +47,7 @@ class Item_sum_int_rcbase : public Item_sum_num {
     maybe_null = null_value = 0;
   }
 
-  void int64_value(int64_t &value_);
+  void int64_value(int64_t &value);
 
   void clear() override;
   bool add() override;
diff --git a/storage/tianmu/types/rc_num.cpp b/storage/tianmu/types/rc_num.cpp
index 8ff5f0122..2b10aa98b 100644
--- a/storage/tianmu/types/rc_num.cpp
+++ b/storage/tianmu/types/rc_num.cpp
@@ -34,8 +34,8 @@ RCNum::RCNum(int64_t value_, short scale, bool is_double_, common::CT attrt) {
   Assign(value_, scale, is_double_, attrt);
 }
 
-RCNum::RCNum(double value_)
-    : value_(*(int64_t *)&value_), scale_(0), is_double_(true), is_dot_(false), attr_type_(common::CT::REAL) {
+RCNum::RCNum(double value)
+    : value_(*(int64_t *)&value), scale_(0), is_double_(true), is_dot_(false), attr_type_(common::CT::REAL) {
   null_ = (value_ == NULL_VALUE_D ? true : false);
 }
 
@@ -51,10 +51,10 @@ RCNum::RCNum(const RCNum &rcn)
 
 RCNum::~RCNum() {}
 
-RCNum &RCNum::Assign(int64_t value_, short scale, bool is_double_, common::CT attrt) {
-  this->value_ = value_;
+RCNum &RCNum::Assign(int64_t value, short scale, bool is_double, common::CT attrt) {
+  this->value_ = value;
   this->scale_ = scale;
-  this->is_double_ = is_double_;
+  this->is_double_ = is_double;
   this->attr_type_ = attrt;
 
   if (scale != -1 && !is_double_) {
@@ -76,8 +76,8 @@ RCNum &RCNum::Assign(int64_t value_, short scale, bool is_double_, common::CT at
   return *this;
 }
 
-RCNum &RCNum::Assign(double value_) {
-  this->value_ = *(int64_t *)&value_;
+RCNum &RCNum::Assign(double value) {
+  this->value_ = *(int64_t *)&value;
   this->scale_ = 0;
   this->is_double_ = true;
   this->is_dot_ = false;
@@ -411,18 +411,18 @@ RCNum &RCNum::operator*=(const RCNum &rcn) {
   return *this;
 }
 
-void fcvt(char *buf_, double val_, int digits_, int *dec_, int *sign_) {
+void fcvt(char *buf, double val, int digits, int *dec, int *sign) {
   static int const fmtlen = 10;
   char format[fmtlen + 1];
-  std::snprintf(format, fmtlen + 1, "%%.%df", digits_);
-  std::snprintf(buf_, digits_, format, val_);
-  int len(std::strlen(buf_));
-  (*sign_) = (buf_[0] == '-') ? 1 : 0;
-  (*sign_) && std::memmove(buf_, buf_ + 1, len);
-  char *pbuf(buf_);
+  std::snprintf(format, fmtlen + 1, "%%.%df", digits);
+  std::snprintf(buf, digits, format, val);
+  int len(std::strlen(buf));
+  (*sign) = (buf[0] == '-') ? 1 : 0;
+  (*sign) && std::memmove(buf, buf + 1, len);
+  char *pbuf(buf);
   ::strsep(&pbuf, ".,");
   if (pbuf) {
-    (*dec_) = pbuf - buf_ - 1;
+    (*dec) = pbuf - buf - 1;
     std::memmove(pbuf - 1, pbuf, std::strlen(pbuf) + 1);
   }
   return;
diff --git a/storage/tianmu/types/text_stat.cpp b/storage/tianmu/types/text_stat.cpp
index b55acb023..5f302de63 100644
--- a/storage/tianmu/types/text_stat.cpp
+++ b/storage/tianmu/types/text_stat.cpp
@@ -28,7 +28,7 @@ TextStat::TextStat() {
 
 bool TextStat::AddString(const BString &rcbs) {
   size_t len = rcbs.size();
-  if (len > TAB_SIZE) {
+  if (len > TAB_SIZE_) {
     valid_ = false;
     return false;
   }
@@ -41,7 +41,7 @@ bool TextStat::AddString(const BString &rcbs) {
     chars_found_[256 * i + uchar(rcbs[i])] = 1;
   }
 
-  if (len < TAB_SIZE)
+  if (len < TAB_SIZE_)
     chars_found_[256 * len] = 1;  // value of len n puts 0 on position n (starting with 0)
   if (len > max_string_size_)
     max_string_size_ = len;
@@ -51,7 +51,7 @@ bool TextStat::AddString(const BString &rcbs) {
 
 bool TextStat::AddChar(uchar v, int pos)  // return false if out of range
 {
-  if (static_cast<size_t>(pos) >= TAB_SIZE || v == 0) {
+  if (static_cast<size_t>(pos) >= TAB_SIZE_ || v == 0) {
     valid_ = false;
     return false;
   }
@@ -64,9 +64,9 @@ bool TextStat::AddChar(uchar v, int pos)  // return false if out of range
 
 void TextStat::AddLen(int pos)  // value of len n puts 0 on position n (starting with 0)
 {
-  if (static_cast<size_t>(pos) == TAB_SIZE)
+  if (static_cast<size_t>(pos) == TAB_SIZE_)
     return;
-  DEBUG_ASSERT(static_cast<size_t>(pos) < TAB_SIZE);
+  DEBUG_ASSERT(static_cast<size_t>(pos) < TAB_SIZE_);
   chars_found_[256 * pos] = 1;
   if (static_cast<size_t>(pos) > max_string_size_)
     max_string_size_ = pos;
@@ -151,7 +151,7 @@ int64_t TextStat::Encode(const BString &rcbs,
 {
   int64_t res = 0;
   size_t len = rcbs.size();
-  if (len > TAB_SIZE)
+  if (len > TAB_SIZE_)
     return common::NULL_VALUE_64;
   int charcode;
   for (size_t i = 0; i < len; i++) {
@@ -205,9 +205,9 @@ BString TextStat::Decode(int64_t code) {
 
   int charcode;
   int len = max_string_size_;
-  char buf_val[TMP_BUFFER_SIZE] = {0};
+  char buf_val[TMP_BUFFER_SIZE_] = {0};
 
-  DEBUG_ASSERT(max_string_size_ < TMP_BUFFER_SIZE);
+  DEBUG_ASSERT(max_string_size_ < TMP_BUFFER_SIZE_);
   buf_val[max_string_size_] = 0;
   for (int i = max_string_size_ - 1; i >= 0; i--) {
     charcode = 0;
diff --git a/storage/tianmu/types/text_stat.h b/storage/tianmu/types/text_stat.h
index 65eac1b33..62ffad48b 100644
--- a/storage/tianmu/types/text_stat.h
+++ b/storage/tianmu/types/text_stat.h
@@ -55,20 +55,20 @@ class TextStat final {
   void Invalidate() { valid_ = false; }
 
  private:
-  static constexpr int TMP_BUFFER_SIZE = 49;
+  static constexpr int TMP_BUFFER_SIZE_ = 49;
 
-  static constexpr size_t TAB_SIZE = 48;
+  static constexpr size_t TAB_SIZE_ = 48;
 
   // binary length of position n, value 0 means that this is a constant
   // character
-  std::array<int, TAB_SIZE> len_table_;
+  std::array<int, TAB_SIZE_> len_table_;
 
   // encode_table[c + 256 * n] is a character for code c on position n
-  std::array<uchar, 256 * TAB_SIZE> encode_table_;
+  std::array<uchar, 256 * TAB_SIZE_> encode_table_;
 
   // a buffer for two purposes: collecting 0/1 info about chars found, or
   // collecting decoding into
-  std::array<uchar, 256 * TAB_SIZE> chars_found_;
+  std::array<uchar, 256 * TAB_SIZE_> chars_found_;
 
   bool chars_found_for_decoding_{false};  // true, if chars_found is initialized for value decoding
   bool valid_{true};