MySQL 8.0.30
Source Code Documentation
index_range_scan_plan.h
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22
23#ifndef SQL_RANGE_OPTIMIZER_INDEX_RANGE_SCAN_PLAN_H_
24#define SQL_RANGE_OPTIMIZER_INDEX_RANGE_SCAN_PLAN_H_
25
26#include <sys/types.h>
27
28#include "my_dbug.h"
29#include "sql/handler.h"
35#include "sql/sql_const.h"
36
38class RANGE_OPT_PARAM;
39class SEL_ROOT;
40class SEL_TREE;
41struct MEM_ROOT;
42
43bool get_ranges_from_tree(MEM_ROOT *return_mem_root, TABLE *table,
44 KEY_PART *key, uint keyno, SEL_ROOT *key_tree,
45 uint num_key_parts, unsigned *used_key_parts,
46 unsigned *num_exact_key_parts, Quick_ranges *ranges);
47
48/*
49 Get best "range" table read plan for given SEL_TREE, also update some info
50
51 SYNOPSIS
52 get_key_scans_params()
53 param Parameters from test_quick_select
54 tree Make range select for this SEL_TREE
55 index_read_must_be_used true <=> assume 'index only' option will be set
56 (except for clustered PK indexes)
57 update_tbl_stats true <=> update table->quick_* with information
58 about range scans we've evaluated.
59 interesting_order The sort order the range access method must be
60 able to provide. Three-value logic:
61 asc/desc/don't care
62 skip_records_in_range Same value as JOIN_TAB::skip_records_in_range().
63 cost_est Maximum cost. i.e. don't create read plans with
64 cost > cost_est.
65 needed_reg ptr to needed_reg argument
66 of test_quick_select().
67
68 DESCRIPTION
69 Find the best "range" table read plan for given SEL_TREE.
70 The side effects are
71 - tree->ror_scans is updated to indicate which scans are ROR scans.
72 - if update_tbl_stats=true then table->quick_* is updated with info
73 about every possible range scan.
74
75 RETURN
76 Best range read plan
77 NULL if no plan found or error occurred
78*/
79
81 SEL_TREE *tree, bool index_read_must_be_used,
82 bool update_tbl_stats,
83 enum_order interesting_order,
84 bool skip_records_in_range, double cost_est,
85 Key_map *needed_reg);
86
87/*
88 Calculate estimate of number records that will be retrieved by a range
89 scan on given index using given SEL_ARG intervals tree.
90
91 SYNOPSIS
92 check_quick_select()
93 param Parameter from test_quick_select
94 idx Number of index to use in RANGE_OPT_PARAM::key
95 SEL_TREE::key
96 index_only true - assume only index tuples will be accessed
97 false - assume full table rows will be read
98 tree Transformed selection condition, tree->key[idx] holds
99 the intervals for the given index.
100 update_tbl_stats true <=> update table->quick_* with information
101 about range scan we've evaluated.
102 order_direction The sort order the range access method must be able
103 to provide. Three-value logic: asc/desc/don't care
104 skip_records_in_range Same value as JOIN_TAB::skip_records_in_range().
105 mrr_flags INOUT MRR access flags
106 cost OUT Scan cost
107 is_ror_scan OUT Set to reflect if the key scan is a ROR
108 (see is_key_scan_ror function for more info)
109 is_imerge_scan OUT Set to reflect if the key scan can be used for
110 index-merge-scan
111
112 NOTES
113 param->table->quick_*, param->range_count (and maybe others) are
114 updated with data of given key scan, see quick_range_seq_next for details.
115
116 RETURN
117 Estimate # of records to be retrieved.
118 HA_POS_ERROR if estimate calculation failed due to table handler problems.
119*/
121 bool index_only, SEL_ROOT *tree,
122 bool update_tbl_stats, enum_order order_direction,
123 bool skip_records_in_range, uint *mrr_flags,
124 uint *bufsize, Cost_estimate *cost,
125 bool *is_ror_scan, bool *is_imerge_scan);
126
127#ifndef NDEBUG
128void dbug_dump_range(int indent, bool verbose, TABLE *table, int index,
129 KEY_PART *used_key_part,
131#endif
132
134 const RANGE_OPT_PARAM *param,
135 Opt_trace_object *trace_object);
136
137#endif // SQL_RANGE_OPTIMIZER_INDEX_RANGE_SCAN_PLAN_H_
Definition: sql_bitmap.h:137
A wrapper class which provides array bounds checking.
Definition: sql_array.h:46
Used to store optimizer cost estimates.
Definition: handler.h:3582
A JSON object (unordered set of key/value pairs).
Definition: opt_trace.h:801
Definition: range_opt_param.h:28
A graph of (possible multiple) key ranges, represented as a red-black binary tree.
Definition: tree.h:67
Definition: tree.h:870
For each client connection we create a separate thread with THD serving as a thread/connection descri...
Definition: sql_class.h:922
AccessPath * get_key_scans_params(THD *thd, RANGE_OPT_PARAM *param, SEL_TREE *tree, bool index_read_must_be_used, bool update_tbl_stats, enum_order interesting_order, bool skip_records_in_range, double cost_est, Key_map *needed_reg)
Definition: index_range_scan_plan.cc:819
ha_rows check_quick_select(THD *thd, RANGE_OPT_PARAM *param, uint idx, bool index_only, SEL_ROOT *tree, bool update_tbl_stats, enum_order order_direction, bool skip_records_in_range, uint *mrr_flags, uint *bufsize, Cost_estimate *cost, bool *is_ror_scan, bool *is_imerge_scan)
Definition: index_range_scan_plan.cc:567
void trace_basic_info_index_range_scan(THD *thd, const AccessPath *path, const RANGE_OPT_PARAM *param, Opt_trace_object *trace_object)
Definition: index_range_scan_plan.cc:793
void dbug_dump_range(int indent, bool verbose, TABLE *table, int index, KEY_PART *used_key_part, Bounds_checked_array< QUICK_RANGE * > ranges)
Definition: index_range_scan_plan.cc:1307
bool get_ranges_from_tree(MEM_ROOT *return_mem_root, TABLE *table, KEY_PART *key, uint keyno, SEL_ROOT *key_tree, uint num_key_parts, unsigned *used_key_parts, unsigned *num_exact_key_parts, Quick_ranges *ranges)
Definition: index_range_scan_plan.cc:771
enum_order
Definition: key_spec.h:64
my_off_t ha_rows
Definition: my_base.h:1139
static uint verbose
Definition: mysqlcheck.cc:64
static char * path
Definition: mysqldump.cc:133
required string key
Definition: replication_asynchronous_connection_failover.proto:59
File containing constants that can be used throughout the server.
Access paths are a query planning structure that correspond 1:1 to iterators, in that an access path ...
Definition: access_path.h:188
Definition: range_optimizer.h:54
The MEM_ROOT is a simple arena, where allocations are carved out of larger blocks.
Definition: my_alloc.h:82
Definition: table.h:1394
unsigned int uint
Definition: uca-dump.cc:29