temporal_analyze.c File Reference

Functions for gathering statistics from temporal alphanumeric columns. More...

#include "general/temporal_analyze.h"
#include <assert.h>
#include <math.h>
#include <access/tuptoaster.h>
#include <catalog/pg_collation.h>
#include <catalog/pg_operator.h>
#include <commands/vacuum.h>
#include <parser/parse_oper.h>
#include <utils/datum.h>
#include <utils/fmgrprotos.h>
#include <utils/lsyscache.h>
#include <utils/timestamp.h>
#include "general/period.h"
#include "general/time_analyze.h"
#include "general/rangetypes_ext.h"
#include "general/temporaltypes.h"
#include "general/tempcache.h"
#include "general/temporal_util.h"

Include dependency graph for temporal_analyze.c:

Macros
#define	TEMPORAL_WIDTH_THRESHOLD   4096

Functions
static int	range_bound_qsort_cmp (const void *a1, const void *a2, void *arg)
	Comparison function for sorting RangeBounds. More...
void	range_compute_stats (VacAttrStats *stats, int non_null_cnt, int *slot_idx, RangeBound *lowers, RangeBound *uppers, float8 *lengths, TypeCacheEntry *typcache, Oid rangetypid)
	Compute statistics for the value dimension (that is ranges) for temporal numbers. More...
static void	temp_compute_stats (VacAttrStats *stats, AnalyzeAttrFetchFunc fetchfunc, int samplerows, bool valuestats)
	Compute statistics for temporal columns. More...
void	temporal_extra_info (VacAttrStats *stats)
	Collect extra information about the temporal type and its base and time types. More...
void	temporal_compute_stats (VacAttrStats *stats, AnalyzeAttrFetchFunc fetchfunc, int samplerows, double totalrows)
	Compute the statistics for temporal columns where only the time dimension is considered. More...
void	tnumber_compute_stats (VacAttrStats *stats, AnalyzeAttrFetchFunc fetchfunc, int samplerows, double totalrows)
	Compute the statistics for temporal number columns. More...
Datum	generic_analyze (FunctionCallInfo fcinfo, void(*func)(VacAttrStats *, AnalyzeAttrFetchFunc, int, double))
	Generic analyze function for temporal columns. More...
PGDLLEXPORT Datum	temporal_analyze (PG_FUNCTION_ARGS)
	Compute the statistics for temporal columns where only the time dimension is considered. More...
PGDLLEXPORT Datum	tnumber_analyze (PG_FUNCTION_ARGS)
	Compute the statistics for temporal number columns. More...

Variables
TemporalAnalyzeExtraData *	temporal_extra_data

Detailed Description

Functions for gathering statistics from temporal alphanumeric columns.

Various kind of statistics are collected for both the value and the time dimension of temporal types. Please refer to the PostgreSQL file pg_statistic_d.h for more information about the statistics collected.

• Slot 1
  • stakind contains the type of statistics which is STATISTIC_KIND_BOUNDS_HISTOGRAM.
  • staop contains the "<" operator of the value dimension.
  • stavalues stores the histogram of ranges for the value dimension.
  • numvalues contains the number of buckets in the histogram.
• Slot 2
  • stakind contains the type of statistics which is STATISTIC_KIND_RANGE_LENGTH_HISTOGRAM.
  • staop contains the "<" operator to the value dimension.
  • stavalues stores the length of the histogram of ranges for the value dimension.
  • numvalues contains the number of buckets in the histogram.
• Slot 3
  • stakind contains the type of statistics which is STATISTIC_KIND_PERIOD_BOUNDS_HISTOGRAM.
  • staop contains the "<" operator of the time dimension.
  • stavalues stores the histogram of periods for the time dimension.
  • numvalues contains the number of buckets in the histogram.
• Slot 4
  • stakind contains the type of statistics which is STATISTIC_KIND_PERIOD_LENGTH_HISTOGRAM.
  • staop contains the "<" operator of the time dimension.
  • stavalues stores the length of the histogram of periods for the time dimension.
  • numvalues contains the number of buckets in the histogram.

In the case of temporal types having a Period as bounding box, that is, tbool and ttext, no statistics are collected for the value dimension and the statistics for the temporal part are stored in slots 1 and 2.