MDEV-18755 Assertion `inited==INDEX' failed in handler::ha_index_read_map

When the chosen execution plan accesses a join table employing a range
rowid filter a quick select to scan this range has to be built. This
quick select is built by a call of SQL_SELECT::test_quick_select().
At this call the function should allow to evaluate only single index
range scans. In order to be able to do this a new parameter was added
to this function.

mysql-test/main/rowid_filter.result

@@ -1940,4 +1940,5 @@ ALTER TABLE orders DROP CONSTRAINT o_price;
 ALTER TABLE orders DROP COLUMN o_totaldiscount;
 DROP VIEW v1;
 DROP DATABASE dbt3_s001;
+use test;
 set @@use_stat_tables=@save_use_stat_tables;

mysql-test/main/rowid_filter.test

@@ -228,4 +228,6 @@ DROP VIEW v1;
 
 DROP DATABASE dbt3_s001;
 
+use test;
+
 set @@use_stat_tables=@save_use_stat_tables;

mysql-test/main/rowid_filter_innodb.result

@@ -1869,5 +1869,114 @@ ALTER TABLE orders DROP CONSTRAINT o_price;
 ALTER TABLE orders DROP COLUMN o_totaldiscount;
 DROP VIEW v1;
 DROP DATABASE dbt3_s001;
+use test;
 set @@use_stat_tables=@save_use_stat_tables;
+#
+# MDEV-18755: possible RORI-plan and possible plan with range filter
+#
+create table t1 (
+pk int not null primary key, f1 varchar(10), f2 varchar(30), a int(10),
+key (f1), key (f2)
+) engine=innodb;
+insert into t1 values
+(2,'a','a',2),(3,'a','a',null),(4,'a','a',55),(5,'a','a',4),(6,'a','a',0),
+(7,'a','a',1),(8,'a','a',4),(9,'a','a',null),(10,'a','a',0),(11,'a','a',0),
+(12,'a','a',null),(13,'a','a',49778),(14,'a','a',6),(15,'a','a',3),
+(16,'a','a',233),(17,'a','a',-1),(18,'a','a',5),(19,'a','a',-1),
+(20,'a','a',null),(21,'a','a',0),(22,'a','a',null),(23,'a','a',53840),
+(24,'a','a',null),(25,'a','a',null),(26,'a','a',5),(27,'a','a',43454),
+(28,'a','a',0),(29,'a','a',0),(30,'a','a',null),(59,'a','a',null),
+(60,'a','a',null),(61,'a','a',-1),(62,'a','a',null),(63,'a','a',0),
+(64,'a','a',14468),(65,'a','a',0),(66,'a','a',28),(67,'a','a',null),
+(68,'a','a',14983),(69,'a','a',null),(70,'a','a',3),(71,'a','a',null),
+(72,'a','a',null),(73,'a','a',237),(74,'a','a',2),(75,'a','a',0),
+(76,'a','a',6),(77,'a','a',5),(78,'a','a',0),(79,'a','a',1),(80,'a','a',-1),
+(81,'a','a',20),(82,'a','a',0),(83,'a','a',0),(84,'a','a',null),
+(85,'a','a',-1),(86,'a','a',5),(87,'a','a',null),(88,'a','a',160),
+(89,null,null,null),(90,'a','a',14785),(91,'a','a',0),(92,'a','a',null);
+( select * from t1
+where (f1 is null and f2 is null) and (f2 between 'a' and 'z' or f1 in ('a')))
+union
+( select * from t1
+where (f1 is null and f2 is null) and (f2 between 'a' and 'z' or f1 in ('a')));
+pk	f1	f2	a
+explain ( select * from t1
+where (f1 is null and f2 is null) and (f2 between 'a' and 'z' or f1 in ('a')))
+union
+( select * from t1
+where (f1 is null and f2 is null) and (f2 between 'a' and 'z' or f1 in ('a')));
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ref|filter	f1,f2	f2|f1	33|13	const	1 (2%)	Using index condition; Using where; Using rowid filter
+2	UNION	t1	ref|filter	f1,f2	f2|f1	33|13	const	1 (2%)	Using index condition; Using where; Using rowid filter
+NULL	UNION RESULT	<union1,2>	ALL	NULL	NULL	NULL	NULL	NULL	
+explain format=json ( select * from t1
+where (f1 is null and f2 is null) and (f2 between 'a' and 'z' or f1 in ('a')))
+union
+( select * from t1
+where (f1 is null and f2 is null) and (f2 between 'a' and 'z' or f1 in ('a')));
+EXPLAIN
+{
+  "query_block": {
+    "union_result": {
+      "table_name": "<union1,2>",
+      "access_type": "ALL",
+      "query_specifications": [
+        {
+          "query_block": {
+            "select_id": 1,
+            "table": {
+              "table_name": "t1",
+              "access_type": "ref",
+              "possible_keys": ["f1", "f2"],
+              "key": "f2",
+              "key_length": "33",
+              "used_key_parts": ["f2"],
+              "ref": ["const"],
+              "rowid_filter": {
+                "range": {
+                  "key": "f1",
+                  "used_key_parts": ["f1"]
+                },
+                "rows": 1,
+                "selectivity_pct": 1.5873
+              },
+              "rows": 1,
+              "filtered": 100,
+              "index_condition": "t1.f2 is null",
+              "attached_condition": "t1.f1 is null and (t1.f2 between 'a' and 'z' or t1.f1 = 'a')"
+            }
+          }
+        },
+        {
+          "query_block": {
+            "select_id": 2,
+            "operation": "UNION",
+            "table": {
+              "table_name": "t1",
+              "access_type": "ref",
+              "possible_keys": ["f1", "f2"],
+              "key": "f2",
+              "key_length": "33",
+              "used_key_parts": ["f2"],
+              "ref": ["const"],
+              "rowid_filter": {
+                "range": {
+                  "key": "f1",
+                  "used_key_parts": ["f1"]
+                },
+                "rows": 1,
+                "selectivity_pct": 1.5873
+              },
+              "rows": 1,
+              "filtered": 100,
+              "index_condition": "t1.f2 is null",
+              "attached_condition": "t1.f1 is null and (t1.f2 between 'a' and 'z' or t1.f1 = 'a')"
+            }
+          }
+        }
+      ]
+    }
+  }
+}
+drop table t1;
 SET SESSION STORAGE_ENGINE=DEFAULT;

mysql-test/main/rowid_filter_innodb.test

@@ -4,4 +4,44 @@ SET SESSION STORAGE_ENGINE='InnoDB';
 
 --source rowid_filter.test
 
+--echo #
+--echo # MDEV-18755: possible RORI-plan and possible plan with range filter
+--echo #
+
+create table t1 (
+  pk int not null primary key, f1 varchar(10), f2 varchar(30), a int(10),
+  key (f1), key (f2)
+) engine=innodb;
+
+insert into t1 values
+  (2,'a','a',2),(3,'a','a',null),(4,'a','a',55),(5,'a','a',4),(6,'a','a',0),
+  (7,'a','a',1),(8,'a','a',4),(9,'a','a',null),(10,'a','a',0),(11,'a','a',0),
+  (12,'a','a',null),(13,'a','a',49778),(14,'a','a',6),(15,'a','a',3),
+  (16,'a','a',233),(17,'a','a',-1),(18,'a','a',5),(19,'a','a',-1),
+  (20,'a','a',null),(21,'a','a',0),(22,'a','a',null),(23,'a','a',53840),
+  (24,'a','a',null),(25,'a','a',null),(26,'a','a',5),(27,'a','a',43454),
+  (28,'a','a',0),(29,'a','a',0),(30,'a','a',null),(59,'a','a',null),
+  (60,'a','a',null),(61,'a','a',-1),(62,'a','a',null),(63,'a','a',0),
+  (64,'a','a',14468),(65,'a','a',0),(66,'a','a',28),(67,'a','a',null),
+  (68,'a','a',14983),(69,'a','a',null),(70,'a','a',3),(71,'a','a',null),
+  (72,'a','a',null),(73,'a','a',237),(74,'a','a',2),(75,'a','a',0),
+  (76,'a','a',6),(77,'a','a',5),(78,'a','a',0),(79,'a','a',1),(80,'a','a',-1),
+  (81,'a','a',20),(82,'a','a',0),(83,'a','a',0),(84,'a','a',null),
+  (85,'a','a',-1),(86,'a','a',5),(87,'a','a',null),(88,'a','a',160),
+  (89,null,null,null),(90,'a','a',14785),(91,'a','a',0),(92,'a','a',null);
+
+let $q=
+( select * from t1
+    where (f1 is null and f2 is null) and (f2 between 'a' and 'z' or f1 in ('a')))
+  union
+( select * from t1
+    where (f1 is null and f2 is null) and (f2 between 'a' and 'z' or f1 in ('a')));
+
+eval $q;
+eval explain $q;
+eval explain format=json $q;
+
+drop table t1;
+
+
 SET SESSION STORAGE_ENGINE=DEFAULT;

sql/opt_range.cc

@@ -2586,6 +2586,9 @@ static int fill_used_fields_bitmap(PARAM *param)
       limit             Query limit
       force_quick_range Prefer to use range (instead of full table scan) even
                         if it is more expensive.
+      remove_false_parts_of_where  Remove parts of OR-clauses for which range
+                                   analysis produced SEL_TREE(IMPOSSIBLE)
+      only_single_index_range_scan Evaluate only single index range scans
 
   NOTES
     Updates the following in the select parameter:
@@ -2644,7 +2647,8 @@ int SQL_SELECT::test_quick_select(THD *thd, key_map keys_to_use,
 				  table_map prev_tables,
 				  ha_rows limit, bool force_quick_range, 
                                   bool ordered_output,
-                                  bool remove_false_parts_of_where)
+                                  bool remove_false_parts_of_where,
+                                  bool only_single_index_range_scan)
 {
   uint idx;
   double scan_time;
@@ -2824,7 +2828,7 @@ int SQL_SELECT::test_quick_select(THD *thd, key_map keys_to_use,
     }
 
     TABLE_READ_PLAN *best_trp= NULL;
-    TRP_GROUP_MIN_MAX *group_trp;
+    TRP_GROUP_MIN_MAX *group_trp= NULL;
     double best_read_time= read_time;
 
     if (cond)
@@ -2859,7 +2863,8 @@ int SQL_SELECT::test_quick_select(THD *thd, key_map keys_to_use,
       Try to construct a QUICK_GROUP_MIN_MAX_SELECT.
       Notice that it can be constructed no matter if there is a range tree.
     */
-    group_trp= get_best_group_min_max(&param, tree, best_read_time);
+    if (!only_single_index_range_scan)
+      group_trp= get_best_group_min_max(&param, tree, best_read_time);
     if (group_trp)
     {
       param.table->quick_condition_rows= MY_MIN(group_trp->records,
@@ -2907,7 +2912,8 @@ int SQL_SELECT::test_quick_select(THD *thd, key_map keys_to_use,
         table deletes.
       */
       if ((thd->lex->sql_command != SQLCOM_DELETE) && 
-           optimizer_flag(thd, OPTIMIZER_SWITCH_INDEX_MERGE))
+           optimizer_flag(thd, OPTIMIZER_SWITCH_INDEX_MERGE) &&
+          !only_single_index_range_scan)
       {
         /*
           Get best non-covering ROR-intersection plan and prepare data for
@@ -2935,7 +2941,8 @@ int SQL_SELECT::test_quick_select(THD *thd, key_map keys_to_use,
       */
       if (param.table->covering_keys.is_clear_all() &&
           optimizer_flag(thd, OPTIMIZER_SWITCH_INDEX_MERGE) &&
-          optimizer_flag(thd, OPTIMIZER_SWITCH_INDEX_MERGE_SORT_INTERSECT))
+          optimizer_flag(thd, OPTIMIZER_SWITCH_INDEX_MERGE_SORT_INTERSECT) &&
+          !only_single_index_range_scan)
       {
         if ((intersect_trp= get_best_index_intersect(&param, tree,
                                                     best_read_time)))
@@ -2948,7 +2955,7 @@ int SQL_SELECT::test_quick_select(THD *thd, key_map keys_to_use,
       }
 
       if (optimizer_flag(thd, OPTIMIZER_SWITCH_INDEX_MERGE) &&
-          head->stat_records() != 0)
+          head->stat_records() != 0 && !only_single_index_range_scan)
       {
         /* Try creating index_merge/ROR-union scan. */
         SEL_IMERGE *imerge;

sql/opt_range.h

@@ -1645,7 +1645,8 @@ class SQL_SELECT :public Sql_alloc {
   {
     key_map tmp;
     tmp.set_all();
-    return test_quick_select(thd, tmp, 0, limit, force_quick_range, FALSE, FALSE) < 0;
+    return test_quick_select(thd, tmp, 0, limit, force_quick_range,
+                             FALSE, FALSE, FALSE) < 0;
   }
   /* 
     RETURN
@@ -1662,7 +1663,8 @@ class SQL_SELECT :public Sql_alloc {
   }
   int test_quick_select(THD *thd, key_map keys, table_map prev_tables,
 			ha_rows limit, bool force_quick_range, 
-                        bool ordered_output, bool remove_false_parts_of_where);
+                        bool ordered_output, bool remove_false_parts_of_where,
+                        bool only_single_index_range_scan);
 };
 
 

sql/sql_select.cc

@@ -1606,7 +1606,7 @@ bool JOIN::make_range_rowid_filters()
     tab->table->force_index= true;
     (void) sel->test_quick_select(thd, filter_map, (table_map) 0,
                                   (ha_rows) HA_POS_ERROR,
-				  true, false, true);
+                                  true, false, true, true);
     tab->table->force_index= force_index_save;
     if (thd->is_error())
       goto no_filter;
@@ -4623,7 +4623,8 @@ static ha_rows get_quick_record_count(THD *thd, SQL_SELECT *select,
                 select->test_quick_select(thd, *(key_map *)keys,
                                           (table_map) 0,
                                           limit, 0, FALSE,
-                                          TRUE /* remove_where_parts*/)) ==
+                                          TRUE,     /* remove_where_parts*/
+                                          FALSE)) ==
                1))
       DBUG_RETURN(select->quick->records);
     if (unlikely(error == -1))
@@ -11356,7 +11357,7 @@ make_join_select(JOIN *join,SQL_SELECT *select,COND *cond)
 					OPTION_FOUND_ROWS ?
 					HA_POS_ERROR :
 					join->unit->select_limit_cnt), 0,
-                                        FALSE, FALSE) < 0)
+                                       FALSE, FALSE, FALSE) < 0)
             {
 	      /*
 		Before reporting "Impossible WHERE" for the whole query
@@ -11370,7 +11371,7 @@ make_join_select(JOIN *join,SQL_SELECT *select,COND *cond)
                                           OPTION_FOUND_ROWS ?
                                           HA_POS_ERROR :
                                           join->unit->select_limit_cnt),0,
-                                          FALSE, FALSE) < 0)
+                                         FALSE, FALSE, FALSE) < 0)
 		DBUG_RETURN(1);			// Impossible WHERE
             }
             else
@@ -20899,7 +20900,8 @@ test_if_quick_select(JOIN_TAB *tab)
 
   int res= tab->select->test_quick_select(tab->join->thd, tab->keys,
                                           (table_map) 0, HA_POS_ERROR, 0,
-                                          FALSE, /*remove where parts*/FALSE);
+                                          FALSE, /*remove where parts*/FALSE,
+                                          FALSE);
   if (tab->explain_plan && tab->explain_plan->range_checked_fer)
     tab->explain_plan->range_checked_fer->collect_data(tab->select->quick);
 
@@ -22763,9 +22765,9 @@ test_if_skip_sort_order(JOIN_TAB *tab,ORDER *order,ha_rows select_limit,
           res= select->test_quick_select(tab->join->thd, new_ref_key_map, 0,
                                          (tab->join->select_options &
                                           OPTION_FOUND_ROWS) ?
-                                         HA_POS_ERROR :
+                                          HA_POS_ERROR :
-                                         tab->join->unit->select_limit_cnt,TRUE,
+                                          tab->join->unit->select_limit_cnt,TRUE,
-                                         TRUE, FALSE) <= 0;
+                                         TRUE, FALSE, FALSE) <= 0;
           if (res)
           {
             select->cond= save_cond;
@@ -22867,7 +22869,7 @@ test_if_skip_sort_order(JOIN_TAB *tab,ORDER *order,ha_rows select_limit,
                                 join->select_options & OPTION_FOUND_ROWS ?
                                 HA_POS_ERROR :
                                 join->unit->select_limit_cnt,
-                                TRUE, FALSE, FALSE);
+                                TRUE, FALSE, FALSE, FALSE);
 
       if (cond_saved)
         select->cond= saved_cond;