mariadb/sql/sql_analyse.h

#ifndef SQL_ANALYSE_INCLUDED
#define SQL_ANALYSE_INCLUDED

/* Copyright (c) 2000, 2010, Oracle and/or its affiliates.
   Copyright (c) 2010, 2026, MariaDB plc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   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.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */


/* Analyse database */

#include "procedure.h"                          /* Procedure */
#include "sql_tree.h"

#define my_thd_charset	default_charset_info

#define DEC_IN_AVG 4

typedef struct st_number_info
{
  // if zerofill is true, the number must be zerofill, or string
  bool	    negative, is_float, zerofill, maybe_zerofill;
  int8	    integers;
  int8	    decimals;
  double    dval;
  ulonglong ullval;
} NUM_INFO;

typedef struct st_extreme_value_number_info
{
  ulonglong ullval;
  longlong  llval;
  double    max_dval, min_dval;
} EV_NUM_INFO;

typedef struct st_tree_info
{
  bool	 found;
  String *str;
  Item	 *item;
} TREE_INFO;

uint check_ulonglong(const char *str, uint length);
bool get_ev_num_info(EV_NUM_INFO *ev_info, NUM_INFO *info, const char *num);
bool test_if_number(NUM_INFO *info, const char *str, uint str_len);
int compare_double(const double *s, const double *t);
int compare_double2(void *, const void *s, const void *t);
int compare_longlong(const longlong *s, const longlong *t);
int compare_longlong2(void *, const void *s, const void *t);
int compare_ulonglong(const ulonglong *s, const ulonglong *t);
int compare_ulonglong2(void *, const void *s, const void *t);
int compare_decimal2(void *len, const void *s, const void *t);
Procedure *proc_analyse_init(THD *thd, ORDER *param, select_result *result,
			     List<Item> &field_list);

struct DecimalKey
{
  uchar data[DECIMAL_MAX_FIELD_SIZE];
};

class analyse;

class field_info :public Sql_alloc
{
protected:
  ulong   treemem, tree_elements, empty, nulls, min_length, max_length;
  uint	  room_in_tree;
  bool found;
  Item	  *item;
  analyse *pc;

public:
  field_info(Item* a, analyse* b) : treemem(0), tree_elements(0), empty(0),
    nulls(0), min_length(0), max_length(0), room_in_tree(1),
    found(0),item(a), pc(b) {};

  virtual ~field_info() = default;
  virtual void	 add() = 0;
  virtual void	 get_opt_type(String*, ha_rows) = 0;
  virtual String *get_min_arg(String *) = 0;
  virtual String *get_max_arg(String *) = 0;
  virtual String *avg(String*, ha_rows) = 0;
  virtual String *std(String*, ha_rows) = 0;
  virtual void   walk_tree(TREE_INFO *) = 0;
  virtual uint   tree_size() const = 0;
  virtual uint decimals() { return 0; }
  friend  class analyse;
};

int collect_string(const String &element, element_count count, TREE_INFO &info);

int sortcmp2(void *, const void *a, const void *b);

class field_str :public field_info
{
  String      min_arg, max_arg;
  ulonglong   sum;
  bool	      must_be_blob, was_zero_fill, was_maybe_zerofill,
	      can_be_still_num;
  NUM_INFO    num_info;
  EV_NUM_INFO ev_num_info;
  Tree<String> tree;

public:
  field_str(Item* a, analyse* b) :field_info(a,b),
    min_arg("",0,default_charset_info),
    max_arg("",0,default_charset_info), sum(0),
    must_be_blob(0), was_zero_fill(0),
    was_maybe_zerofill(0), can_be_still_num(1),
    tree(sortcmp2, nullptr, MYF(MY_THREAD_SPECIFIC))
    {};

  void	 add() override;
  void	 get_opt_type(String*, ha_rows) override;
  String *get_min_arg(String *not_used __attribute__((unused))) override
  { return &min_arg; }
  String *get_max_arg(String *not_used __attribute__((unused))) override
  { return &max_arg; }
  String *avg(String *s, ha_rows rows) override
  {
    if (!(rows - nulls))
      s->set_real((double) 0.0, 1,my_thd_charset);
    else
      s->set_real((ulonglong2double(sum) / ulonglong2double(rows - nulls)),
	     DEC_IN_AVG,my_thd_charset);
    return s;
  }
  void   walk_tree(TREE_INFO *info) override;
  uint   tree_size() const override { return tree.elements(); }
  friend int collect_string(const String &element, element_count count,
			    TREE_INFO &info);
  String *std(String *s __attribute__((unused)),
	      ha_rows rows __attribute__((unused))) override
  { return (String*) 0; }
};


int collect_decimal(const DecimalKey &element, element_count count,
                    TREE_INFO &info);

class field_decimal :public field_info
{
  my_decimal min_arg, max_arg;
  my_decimal sum[2], sum_sqr[2];
  int cur_sum;
  int bin_size;
  Tree<DecimalKey, int> tree;
public:
  field_decimal(Item* a, analyse* b) :field_info(a,b),
    bin_size((int) my_decimal_get_binary_size(a->max_length, a->decimals)),
    tree(compare_decimal2, &bin_size, MYF(MY_THREAD_SPECIFIC))
  {};

  void	 add() override;
  void	 get_opt_type(String*, ha_rows) override;
  String *get_min_arg(String *) override;
  String *get_max_arg(String *) override;
  String *avg(String *s, ha_rows rows) override;
  friend int collect_decimal(const DecimalKey &element, element_count count,
                             TREE_INFO &info);
  void   walk_tree(TREE_INFO *info) override;
  uint   tree_size() const override { return tree.elements(); }
  String *std(String *s, ha_rows rows) override;
};


int collect_real(const double &element, element_count count, TREE_INFO &info);

class field_real: public field_info
{
  double min_arg, max_arg;
  double sum, sum_sqr;
  uint	 max_notzero_dec_len;
  Tree<double> tree;

public:
  field_real(Item* a, analyse* b) :field_info(a,b),
    min_arg(0), max_arg(0),  sum(0), sum_sqr(0), max_notzero_dec_len(0),
    tree(compare_double2, nullptr, MYF(MY_THREAD_SPECIFIC))
    {}

  void	 add() override;
  void	 get_opt_type(String*, ha_rows) override;
  String *get_min_arg(String *s) override
  {
    s->set_real(min_arg, item->decimals, my_thd_charset);
    return s;
  }
  String *get_max_arg(String *s) override
  {
    s->set_real(max_arg, item->decimals, my_thd_charset);
    return s;
  }
  String *avg(String *s, ha_rows rows) override
  {
    if (!(rows - nulls))
      s->set_real((double) 0.0, 1,my_thd_charset);
    else
      s->set_real(((double)sum / (double) (rows - nulls)), item->decimals,my_thd_charset);
    return s;
  }
  String *std(String *s, ha_rows rows) override
  {
    double tmp = ulonglong2double(rows);
    if (!(tmp - nulls))
      s->set_real((double) 0.0, 1,my_thd_charset);
    else
    {
      double tmp2 = ((sum_sqr - sum * sum / (tmp - nulls)) /
		     (tmp - nulls));
      s->set_real(((double) tmp2 <= 0.0 ? 0.0 : sqrt(tmp2)), item->decimals,my_thd_charset);
    }
    return s;
  }
  uint	 decimals() override { return item->decimals; }
  void   walk_tree(TREE_INFO *info) override;
  uint   tree_size() const override { return tree.elements(); }
  friend int collect_real(const double &element, element_count count,
			  TREE_INFO &info);
};

int collect_longlong(const longlong &element, element_count count,
                     TREE_INFO &info);

class field_longlong: public field_info
{
  longlong min_arg, max_arg;
  double sum, sum_sqr;
  Tree<longlong> tree;

public:
  field_longlong(Item* a, analyse* b) :field_info(a,b),
    min_arg(0), max_arg(0), sum(0), sum_sqr(0.0),
    tree(compare_longlong2, nullptr, MYF(MY_THREAD_SPECIFIC))
  {}

  void	 add() override;
  void	 get_opt_type(String*, ha_rows) override;
  String *get_min_arg(String *s) override { s->set(min_arg,my_thd_charset); return s; }
  String *get_max_arg(String *s) override { s->set(max_arg,my_thd_charset); return s; }
  String *avg(String *s, ha_rows rows) override
  {
    if (!(rows - nulls))
      s->set_real((double) 0.0, 1,my_thd_charset);
    else
      s->set_real(((double) sum / (double) (rows - nulls)), DEC_IN_AVG,my_thd_charset);
    return s;
  }
  String *std(String *s, ha_rows rows) override
  {
    double tmp = ulonglong2double(rows);
    if (!(tmp - nulls))
      s->set_real((double) 0.0, 1,my_thd_charset);
    else
    {
      double tmp2 = (sum_sqr - sum * sum / (tmp - nulls)) /
		    (tmp - nulls);
      s->set_real(tmp2 <= 0.0 ? 0.0 : sqrt(tmp2), DEC_IN_AVG,my_thd_charset);
    }
    return s;
  }
  void   walk_tree(TREE_INFO *info) override;
  uint   tree_size() const override { return tree.elements(); }
  friend int collect_longlong(const longlong &element, element_count count,
			      TREE_INFO &info);
};

int collect_ulonglong(const ulonglong &element, element_count count,
                      TREE_INFO &info);

class field_ulonglong: public field_info
{
  ulonglong min_arg, max_arg;
  double sum, sum_sqr;
  Tree<ulonglong> tree;

public:
  field_ulonglong(Item* a, analyse * b) :field_info(a,b),
    min_arg(0), max_arg(0), sum(0),sum_sqr(0),
    tree(compare_ulonglong2, nullptr, MYF(MY_THREAD_SPECIFIC))
  {}
  void	 add() override;
  void	 get_opt_type(String*, ha_rows) override;
  String *get_min_arg(String *s) override { s->set(min_arg,my_thd_charset); return s; }
  String *get_max_arg(String *s) override { s->set(max_arg,my_thd_charset); return s; }
  String *avg(String *s, ha_rows rows) override
  {
    if (!(rows - nulls))
      s->set_real((double) 0.0, 1,my_thd_charset);
    else
      s->set_real(sum / ulonglong2double(rows - nulls),
                  DEC_IN_AVG, my_thd_charset);
    return s;
  }
  String *std(String *s, ha_rows rows) override
  {
    double tmp = ulonglong2double(rows);
    if (!(tmp - nulls))
      s->set_real((double) 0.0, 1,my_thd_charset);
    else
    {
      double tmp2 = (sum_sqr -
		    (sum * sum) / (tmp - nulls)) /
		    (tmp - nulls);
      s->set_real(tmp2 <= 0.0 ? 0.0 : sqrt(tmp2), DEC_IN_AVG,my_thd_charset);
    }
    return s;
  }
  void   walk_tree(TREE_INFO *info) override;
  uint   tree_size() const override { return tree.elements(); }
  friend int collect_ulonglong(const ulonglong &element, element_count count,
			       TREE_INFO &info);
};


Procedure *proc_analyse_init(THD *thd, ORDER *param,
			     select_result *result,
			     List<Item> &field_list);

class analyse: public Procedure
{
protected:
  Item_proc    *func_items[10];
  List<Item>   fields, result_fields;
  field_info   **f_info, **f_end;
  ha_rows      rows;
  uint	       output_str_length;

public:
  uint max_tree_elements, max_treemem;

  analyse(select_result *res) :Procedure(res, PROC_NO_SORT), f_info(0),
    rows(0), output_str_length(0) {}

  ~analyse()
  {
    if (f_info)
    {
      for (field_info **f=f_info; f != f_end; f++)
	delete (*f);
    }
  }
  void add() override {}
  bool change_columns(THD *thd, List<Item> &fields) override;
  int  send_row(List<Item> &field_list) override;
  void end_group(void) override {}
  int end_of_records(void) override;
  friend Procedure *proc_analyse_init(THD *thd, ORDER *param,
				      select_result *result,
				      List<Item> &field_list);
};

#endif /* SQL_ANALYSE_INCLUDED */