item_sum.cc File Reference

Sum functions (COUNT, MIN...) More...

#include "sql/item_sum.h"
#include <algorithm>
#include <bitset>
#include <cmath>
#include <cstring>
#include <functional>
#include <memory>
#include <optional>
#include <string>
#include <utility>
#include "decimal.h"
#include "field_types.h"
#include "my_alloc.h"
#include "my_base.h"
#include "my_byteorder.h"
#include "my_compare.h"
#include "my_dbug.h"
#include "my_double2ulonglong.h"
#include "my_sys.h"
#include "mysql/strings/dtoa.h"
#include "mysql/strings/m_ctype.h"
#include "mysql/strings/my_strtoll10.h"
#include "mysql_com.h"
#include "mysqld_error.h"
#include "sql-common/json_dom.h"
#include "sql/aggregate_check.h"
#include "sql/create_field.h"
#include "sql/current_thd.h"
#include "sql/dd/cache/dictionary_client.h"
#include "sql/derror.h"
#include "sql/field.h"
#include "sql/gis/gc_utils.h"
#include "sql/gis/geometries.h"
#include "sql/gis/geometry_extraction.h"
#include "sql/gis/relops.h"
#include "sql/handler.h"
#include "sql/item_cmpfunc.h"
#include "sql/item_func.h"
#include "sql/item_json_func.h"
#include "sql/item_subselect.h"
#include "sql/key_spec.h"
#include "sql/mysqld.h"
#include "sql/parse_tree_helpers.h"
#include "sql/parse_tree_node_base.h"
#include "sql/parse_tree_nodes.h"
#include "sql/parser_yystype.h"
#include "sql/sql_array.h"
#include "sql/sql_class.h"
#include "sql/sql_const.h"
#include "sql/sql_error.h"
#include "sql/sql_exception_handler.h"
#include "sql/sql_executor.h"
#include "sql/sql_lex.h"
#include "sql/sql_list.h"
#include "sql/sql_optimizer.h"
#include "sql/sql_resolver.h"
#include "sql/sql_select.h"
#include "sql/sql_time.h"
#include "sql/sql_tmp_table.h"
#include "sql/srs_fetcher.h"
#include "sql/system_variables.h"
#include "sql/table.h"
#include "sql/temp_table_param.h"
#include "sql/uniques.h"
#include "sql/window.h"
#include "string_with_len.h"

Namespaces
namespace	anonymous_namespace{item_sum.cc}

Functions
static int	simple_generic_key_cmp (const void *arg, const void *a, const void *b)
	Compare keys consisting of single field that cannot be compared as binary. More...
static enum enum_field_types	calc_tmp_field_type (enum enum_field_types table_field_type, Item_result result_type)
static int	simple_raw_key_cmp (const void *arg, const void *key1, const void *key2)
static int	item_sum_distinct_walk (void *element, element_count, void *item)
template<class Char_op , class Int_op >
static void	apply_bit_op (size_t buff_length, const uchar *s1_c_p, uchar *value_bits)
	Helper for Item_sum_bit::add_bits(). More...
static void	add_sample (double *m, double *s, double *s2, ulonglong *count, double nr)
	Calculates the next recurrence value s,s2 using the current sample as input. More...
static void	remove_sample (double *m, double *s, double *s2, ulonglong *count, double nr)
	Removes the earlier calculated recurrence value s,s2 for current sample from the current s,s2 values. More...
static bool	variance_fp_recurrence_next (Item_sum_variance *self, double *m, double *s, double *s2, ulonglong *count, double nr, bool optimize, bool inverse)
	Calculates the next recurrence value for current sample. More...
static double	variance_fp_recurrence_result (double s, double s2, ulonglong count, bool is_sample_variance, bool optimize)
	Calculates variance using one of the two algorithms (See Item_sum_variance) as specified. More...
static bool	min_max_best_so_far (int comparison_result, bool is_min)
	Checks if a value should replace the minimum or maximum value seen so far in the MIN and MAX aggregate functions. More...
int	group_concat_key_cmp_with_distinct (const void *arg, const void *key1, const void *key2)
	Compares the values for fields in expr list of GROUP_CONCAT. More...
int	group_concat_key_cmp_with_order (const void *arg, const void *key1, const void *key2)
	function of sort for syntax: GROUP_CONCAT(expr,... ORDER BY col,... ) More...
int	dump_leaf_key (void *key_arg, element_count count, void *item_arg)
	Append data from current leaf to item->result. More...
std::unique_ptr< gis::Geometrycollection >	anonymous_namespace{item_sum.cc}::filtergeometries (std::unique_ptr< gis::Geometrycollection > geometrycollection, const dd::Spatial_reference_system *srs)

Detailed Description

Sum functions (COUNT, MIN...)

Function Documentation

add_sample()

static void add_sample ( double *  m, double *  s, double *  s2, ulonglong *  count, double  nr  )

static

Calculates the next recurrence value s,s2 using the current sample as input.

m is initialized to the first sample. Its not changed for the later calls.

Parameters

[in,out]	m	recurrence value
[in,out]	s	recurrence value
[in,out]	s2	Square of the recurrence value s
[in,out]	count	Number of rows for which m,s,s2 is calculated
[in]	nr	Current sample

apply_bit_op()

template<class Char_op , class Int_op >

static void apply_bit_op ( size_t  buff_length, const uchar *  s1_c_p, uchar *  value_bits  )

inlinestatic

Helper for Item_sum_bit::add_bits().

Does value_bits = s1_c_p bit_op value_bits.

Template Parameters

Char_op	class offering a bit operation for a uchar: AND, OR or XOR
Int_op	class offering a bit operation for a ulonglong: ditto

Parameters

	buff_length	length of s1_c_p
	s1_c_p	first argument of bit op
[in,out]	value_bits	second argument of bit op, and result

calc_tmp_field_type()

static enum enum_field_types calc_tmp_field_type ( enum enum_field_types  table_field_type, Item_result  result_type  )

static

dump_leaf_key()

int dump_leaf_key	(	void *	key_arg,
		element_count	count,
		void *	item_arg
	)

Append data from current leaf to item->result.

To avoid duplicated warnings in Item_func_group_concat::val_str()

group_concat_key_cmp_with_distinct()

int group_concat_key_cmp_with_distinct	(	const void *	arg,
		const void *	key1,
		const void *	key2
	)

Compares the values for fields in expr list of GROUP_CONCAT.

GROUP_CONCAT([DISTINCT] expr [,expr ...]
         [ORDER BY {unsigned_integer | col_name | expr}
             [ASC | DESC] [,col_name ...]]
         [SEPARATOR str_val])

Return values

-1	: key1 < key2
0	: key1 = key2
1	: key1 > key2

group_concat_key_cmp_with_order()

int group_concat_key_cmp_with_order	(	const void *	arg,
		const void *	key1,
		const void *	key2
	)

function of sort for syntax: GROUP_CONCAT(expr,... ORDER BY col,... )

item_sum_distinct_walk()

static int item_sum_distinct_walk ( void *  element, element_count  , void *  item  )

static

min_max_best_so_far()

static bool min_max_best_so_far ( int  comparison_result, bool  is_min  )

static

Checks if a value should replace the minimum or maximum value seen so far in the MIN and MAX aggregate functions.

Parameters

comparison_result	the result of comparing the current value with the min/max value seen so far (negative if it's smaller, 0 if it's equal, positive if it's greater)
is_min	true if called by MIN, false if called by MAX

Returns

true if the current value should replace the min/max value seen so far

remove_sample()

static void remove_sample ( double *  m, double *  s, double *  s2, ulonglong *  count, double  nr  )

static

Removes the earlier calculated recurrence value s,s2 for current sample from the current s,s2 values.

Called when do_inverse() is true.

Parameters

[in]	m	recurrence value
[in,out]	s	recurrence value
[in,out]	s2	Square of the recurrence value s
[in,out]	count	Number of rows for which s,s2 is calculated
[in]	nr	Current sample

simple_generic_key_cmp()

static int simple_generic_key_cmp ( const void *  arg, const void *  a, const void *  b  )

static

Compare keys consisting of single field that cannot be compared as binary.

Used by the Unique class to compare keys. Will do correct comparisons for all field types.

Parameters

arg	Pointer to the relevant Field class instance
a	left key image
b	right key image

Returns

comparison result

Return values

<	0 if key1 < key2
=	0 if key1 = key2
>	0 if key1 > key2

simple_raw_key_cmp()

static int simple_raw_key_cmp ( const void *  arg, const void *  key1, const void *  key2  )

static

variance_fp_recurrence_next()

static bool variance_fp_recurrence_next ( Item_sum_variance *  self, double *  m, double *  s, double *  s2, ulonglong *  count, double  nr, bool  optimize, bool  inverse  )

static

Calculates the next recurrence value for current sample.

Parameters

[in]	self	The object on which behalf we are computing
[in,out]	m	recurrence value
[in,out]	s	recurrence value
[in,out]	s2	Square of the recurrence value s
[in,out]	count	Number of rows for which m,s,s2 is calculated
[in]	nr	Current sample
[in]	optimize	If set to true is Algorithm II is used to calculate m,s and s2. Else Algorithm I is used to calculate m,s.
[in]	inverse	If set to true, we use formulas from Algorithm II to remove value calculated for s,s2 for sample "nr" from the the current value of (s,s2).

Returns

false if success, true if error

Note: variance_fp_recurrence_next and variance_fp_recurrence_result are used by Item_sum_variance and Item_variance_field classes, which are unrelated, and each need to calculate variance. The difference between the two classes is that the first is used for a mundane SELECT and when used with windowing functions, while the latter is used in a GROUPing SELECT.

variance_fp_recurrence_result()

static double variance_fp_recurrence_result ( double  s, double  s2, ulonglong  count, bool  is_sample_variance, bool  optimize  )

static

Calculates variance using one of the two algorithms (See Item_sum_variance) as specified.

Parameters

[in]	s	Recurrence value
[in]	s2	Square of the recurrence value. Used only by Algorithm II
[in]	count	Number of rows for which variance needs to be calculated.
[in]	is_sample_variance	True if calculating sample variance and false if population variance.
[in]	optimize	True if algorithm II is used to calculate variance.

Return values

Returns

calculated variance value