Fixed bug mdev-4366.

When performing the range analysis for a conjunction the function
calculate_cond_selectivity_for_table should take in to account that
the analysis of some conjuncts may return SEL_ARG::IMPOSSIBLE.

mysql-test/r/selectivity.result

@@ -751,10 +751,10 @@ set histogram_size=@save_histogram_size;
 set histogram_type=@save_histogram_type;
 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
 #
-# Bug mdev-4367: join of a merged empty derived table 
+# Bug mdev-4367: 2-way join with an empty table 
 #                when optimizer_use_condition_selectivity=3
 #
-SET optimizer_use_condition_selectivity=3;
+set optimizer_use_condition_selectivity=3;
 CREATE TABLE t1 (a varchar(1)) ENGINE=MyISAM;
 INSERT INTO t1 VALUES ('j'),('k');
 CREATE TABLE t2 (b varchar(1)) ENGINE=MyISAM;
@@ -764,4 +764,34 @@ SELECT * FROM t1 STRAIGHT_JOIN (t2 JOIN t3 ON c = b AND b > 'z');
 a	b	c
 DROP TABLE t1,t2,t3;
 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
+#
+# Bug mdev-4366: impossible condition on an indexed column discovered after
+#                substitution of constant tables
+#                with optimizer_use_condition_selectivity=3
+#
+CREATE TABLE t1 (pk int PRIMARY KEY, a int);
+INSERT INTO t1 VALUES 
+(1,4), (2,6), (3,3), (4,5);
+CREATE TABLE t2 (b int);
+INSERT INTO t2 VALUES (1), (7);
+set optimizer_use_condition_selectivity=1;
+EXPLAIN EXTENDED
+SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
+Warnings:
+Note	1003	select 1 AS `1` from `test`.`t1` join `test`.`t2` where 0
+SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10;
+1
+set optimizer_use_condition_selectivity=3;
+EXPLAIN EXTENDED
+SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
+Warnings:
+Note	1003	select 1 AS `1` from `test`.`t1` join `test`.`t2` where 0
+SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10;
+1
+DROP TABLE t1,t2;
+set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
 set use_stat_tables=@save_use_stat_tables;

mysql-test/r/selectivity_innodb.result

@@ -758,10 +758,10 @@ set histogram_size=@save_histogram_size;
 set histogram_type=@save_histogram_type;
 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
 #
-# Bug mdev-4367: join of a merged empty derived table 
+# Bug mdev-4367: 2-way join with an empty table 
 #                when optimizer_use_condition_selectivity=3
 #
-SET optimizer_use_condition_selectivity=3;
+set optimizer_use_condition_selectivity=3;
 CREATE TABLE t1 (a varchar(1)) ENGINE=MyISAM;
 INSERT INTO t1 VALUES ('j'),('k');
 CREATE TABLE t2 (b varchar(1)) ENGINE=MyISAM;
@@ -771,6 +771,36 @@ SELECT * FROM t1 STRAIGHT_JOIN (t2 JOIN t3 ON c = b AND b > 'z');
 a	b	c
 DROP TABLE t1,t2,t3;
 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
+#
+# Bug mdev-4366: impossible condition on an indexed column discovered after
+#                substitution of constant tables
+#                with optimizer_use_condition_selectivity=3
+#
+CREATE TABLE t1 (pk int PRIMARY KEY, a int);
+INSERT INTO t1 VALUES 
+(1,4), (2,6), (3,3), (4,5);
+CREATE TABLE t2 (b int);
+INSERT INTO t2 VALUES (1), (7);
+set optimizer_use_condition_selectivity=1;
+EXPLAIN EXTENDED
+SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
+Warnings:
+Note	1003	select 1 AS `1` from `test`.`t1` join `test`.`t2` where 0
+SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10;
+1
+set optimizer_use_condition_selectivity=3;
+EXPLAIN EXTENDED
+SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
+Warnings:
+Note	1003	select 1 AS `1` from `test`.`t1` join `test`.`t2` where 0
+SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10;
+1
+DROP TABLE t1,t2;
+set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
 set use_stat_tables=@save_use_stat_tables;
 set optimizer_switch=@save_optimizer_switch_for_selectivity_test;
 SET SESSION STORAGE_ENGINE=DEFAULT;

mysql-test/t/selectivity.test

@@ -337,11 +337,11 @@ set histogram_type=@save_histogram_type;
 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
 
 --echo #
---echo # Bug mdev-4367: join of a merged empty derived table 
+--echo # Bug mdev-4367: 2-way join with an empty table 
 --echo #                when optimizer_use_condition_selectivity=3
 --echo #
 
-SET optimizer_use_condition_selectivity=3;
+set optimizer_use_condition_selectivity=3;
 
 CREATE TABLE t1 (a varchar(1)) ENGINE=MyISAM;
 INSERT INTO t1 VALUES ('j'),('k');
@@ -357,5 +357,32 @@ DROP TABLE t1,t2,t3;
 
 set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
 
+--echo #
+--echo # Bug mdev-4366: impossible condition on an indexed column discovered after
+--echo #                substitution of constant tables
+--echo #                with optimizer_use_condition_selectivity=3
+--echo #
+
+CREATE TABLE t1 (pk int PRIMARY KEY, a int);
+INSERT INTO t1 VALUES 
+  (1,4), (2,6), (3,3), (4,5);
+
+CREATE TABLE t2 (b int);
+INSERT INTO t2 VALUES (1), (7);
+
+set optimizer_use_condition_selectivity=1;
+EXPLAIN EXTENDED
+SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10;
+SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10;
+
+set optimizer_use_condition_selectivity=3;
+EXPLAIN EXTENDED
+SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10;
+SELECT 1 FROM t1, t2 WHERE pk = 6 AND a = 2 AND b = 10;
+
+DROP TABLE t1,t2;
+
+set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
+
 
 set use_stat_tables=@save_use_stat_tables;

sql/opt_range.cc

@@ -3325,11 +3325,8 @@ bool calculate_cond_selectivity_for_table(THD *thd, TABLE *table, Item *cond)
 
   table->cond_selectivity= 1.0;
 
-#if 0
-#else
   if (table_records == 0)
     DBUG_RETURN(FALSE);
-#endif
   
   if (thd->variables.optimizer_use_condition_selectivity > 2 &&
       !bitmap_is_clear_all(used_fields))
@@ -3338,6 +3335,7 @@ bool calculate_cond_selectivity_for_table(THD *thd, TABLE *table, Item *cond)
     MEM_ROOT alloc;
     SEL_TREE *tree;
     SEL_ARG **key, **end;
+    double rows;
     uint idx= 0;
   
     init_sql_alloc(&alloc, thd->variables.range_alloc_block_size, 0,
@@ -3364,12 +3362,18 @@ bool calculate_cond_selectivity_for_table(THD *thd, TABLE *table, Item *cond)
     if (!tree)
       goto free_alloc;
     
+    table->reginfo.impossible_range= 0;
+    if (tree->type == SEL_TREE::IMPOSSIBLE)
+    {
+      rows= 0;
+      table->reginfo.impossible_range= 1;
+      goto free_alloc;
+    }          
+
     for (key= tree->keys, end= key + param.keys; key != end; key++, idx++)
     {
-      double rows;
       if (*key)
       {
-        table->reginfo.impossible_range= 0;
         if ((*key)->type == SEL_ARG::IMPOSSIBLE)
 	{
           rows= 0;