Data structure storing index statistics for query optimization. More...

#include <dict0mem.h>

Public Attributes
uint64_t *	n_diff_key_vals
	approximate number of different key values for this index, for each n-column prefix where 1 <= n <= dict_get_n_unique(index) (the array is indexed from 0 to n_uniq-1); we periodically calculate new estimates More...

uint64_t *	n_sample_sizes
	number of pages that were sampled to calculate each of n_diff_key_vals[], e.g. More...

uint64_t *	n_non_null_key_vals

ulint	index_size
	approximate index size in database pages More...

ulint	n_leaf_pages
	approximate number of leaf pages in the index tree More...

Detailed Description

Data structure storing index statistics for query optimization.

Member Data Documentation

◆ index_size

ulint dict_index_stats_t::index_size

approximate index size in database pages

◆ n_diff_key_vals

uint64_t* dict_index_stats_t::n_diff_key_vals

approximate number of different key values for this index, for each n-column prefix where 1 <= n <= dict_get_n_unique(index) (the array is indexed from 0 to n_uniq-1); we periodically calculate new estimates

◆ n_leaf_pages

ulint dict_index_stats_t::n_leaf_pages

approximate number of leaf pages in the index tree

◆ n_non_null_key_vals

uint64_t* dict_index_stats_t::n_non_null_key_vals

◆ n_sample_sizes

uint64_t* dict_index_stats_t::n_sample_sizes

number of pages that were sampled to calculate each of n_diff_key_vals[], e.g.

stat_n_sample_sizes[3] pages were sampled to get the number n_diff_key_vals[3].

The documentation for this struct was generated from the following file:

storage/innobase/include/dict0mem.h