Bug#33516898: BIGINT converted to UNSIGNED_BIGINT with boolean operation

Bug#33117410 changed the resolved type of a boolean expression
from signed integer to unsigned bigint, in order to simplify the
type handling and facilitate another bugfix. However, what appeared
as a harmless metadata change turned out to be a more serious issue
for various connectors.

This patch will revert the metadata change. It will also fix the
actual problem solved by that change in a slightly different manner,
by adjusting "max_length" for a negation of an integer to at least
two characters.

No test case is required, the metadata decision is sufficiently
documented in the test cases.

Change-Id: Ifb5e98bdef347cbddef0be082e13cd8eecaebb48

Author: roylyseng

mysql-test/r/regular_expressions_utf-8.result

@@ -913,7 +913,7 @@ SHOW CREATE TABLE t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
   `a` bigint NOT NULL DEFAULT '0',
-  `b` int unsigned NOT NULL DEFAULT '0',
+  `b` int NOT NULL DEFAULT '0',
   `c` longtext CHARACTER SET latin1 NOT NULL,
   `d` varchar(1) CHARACTER SET latin1 DEFAULT NULL,
   `e` varchar(512) CHARACTER SET latin1 DEFAULT NULL,

mysql-test/r/view.result

@@ -3328,42 +3328,42 @@ ISNULL(d)
 from table_24532;
 describe view_24532_a;
 Field	Type	Null	Key	Default	Extra
-a IS TRUE	int unsigned	NO		0	
-a IS NOT TRUE	int unsigned	NO		0	
-a IS FALSE	int unsigned	NO		0	
-a IS NOT FALSE	int unsigned	NO		0	
-a IS UNKNOWN	int unsigned	NO		0	
-a IS NOT UNKNOWN	int unsigned	NO		0	
-a is NULL	int unsigned	NO		0	
-a IS NOT NULL	int unsigned	NO		0	
-ISNULL(a)	int unsigned	NO		0	
-b IS TRUE	int unsigned	NO		0	
-b IS NOT TRUE	int unsigned	NO		0	
-b IS FALSE	int unsigned	NO		0	
-b IS NOT FALSE	int unsigned	NO		0	
-b IS UNKNOWN	int unsigned	NO		0	
-b IS NOT UNKNOWN	int unsigned	NO		0	
-b is NULL	int unsigned	NO		0	
-b IS NOT NULL	int unsigned	NO		0	
-ISNULL(b)	int unsigned	NO		0	
-c IS TRUE	int unsigned	NO		0	
-c IS NOT TRUE	int unsigned	NO		0	
-c IS FALSE	int unsigned	NO		0	
-c IS NOT FALSE	int unsigned	NO		0	
-c IS UNKNOWN	int unsigned	NO		0	
-c IS NOT UNKNOWN	int unsigned	NO		0	
-c is NULL	int unsigned	NO		0	
-c IS NOT NULL	int unsigned	NO		0	
-ISNULL(c)	int unsigned	NO		0	
-d IS TRUE	int unsigned	NO		0	
-d IS NOT TRUE	int unsigned	NO		0	
-d IS FALSE	int unsigned	NO		0	
-d IS NOT FALSE	int unsigned	NO		0	
-d IS UNKNOWN	int unsigned	NO		0	
-d IS NOT UNKNOWN	int unsigned	NO		0	
-d is NULL	int unsigned	NO		0	
-d IS NOT NULL	int unsigned	NO		0	
-ISNULL(d)	int unsigned	NO		0	
+a IS TRUE	int	NO		0	
+a IS NOT TRUE	int	NO		0	
+a IS FALSE	int	NO		0	
+a IS NOT FALSE	int	NO		0	
+a IS UNKNOWN	int	NO		0	
+a IS NOT UNKNOWN	int	NO		0	
+a is NULL	int	NO		0	
+a IS NOT NULL	int	NO		0	
+ISNULL(a)	int	NO		0	
+b IS TRUE	int	NO		0	
+b IS NOT TRUE	int	NO		0	
+b IS FALSE	int	NO		0	
+b IS NOT FALSE	int	NO		0	
+b IS UNKNOWN	int	NO		0	
+b IS NOT UNKNOWN	int	NO		0	
+b is NULL	int	NO		0	
+b IS NOT NULL	int	NO		0	
+ISNULL(b)	int	NO		0	
+c IS TRUE	int	NO		0	
+c IS NOT TRUE	int	NO		0	
+c IS FALSE	int	NO		0	
+c IS NOT FALSE	int	NO		0	
+c IS UNKNOWN	int	NO		0	
+c IS NOT UNKNOWN	int	NO		0	
+c is NULL	int	NO		0	
+c IS NOT NULL	int	NO		0	
+ISNULL(c)	int	NO		0	
+d IS TRUE	int	NO		0	
+d IS NOT TRUE	int	NO		0	
+d IS FALSE	int	NO		0	
+d IS NOT FALSE	int	NO		0	
+d IS UNKNOWN	int	NO		0	
+d IS NOT UNKNOWN	int	NO		0	
+d is NULL	int	NO		0	
+d IS NOT NULL	int	NO		0	
+ISNULL(d)	int	NO		0	
 create view view_24532_b as
 select
 a IS TRUE,
@@ -3377,13 +3377,13 @@ if(ifnull(a, 1), 1, 0) as old_isnotfalse
 from table_24532;
 describe view_24532_b;
 Field	Type	Null	Key	Default	Extra
-a IS TRUE	int unsigned	NO		0	
+a IS TRUE	int	NO		0	
 old_istrue	int	NO		0	
-a IS NOT TRUE	int unsigned	NO		0	
+a IS NOT TRUE	int	NO		0	
 old_isnottrue	int	NO		0	
-a IS FALSE	int unsigned	NO		0	
+a IS FALSE	int	NO		0	
 old_isfalse	int	NO		0	
-a IS NOT FALSE	int unsigned	NO		0	
+a IS NOT FALSE	int	NO		0	
 old_isnotfalse	int	NO		0	
 show create view view_24532_b;
 View	Create View	character_set_client	collation_connection

mysql-test/suite/sysschema/r/v_schema_auto_increment_columns_cs.result

@@ -5,8 +5,8 @@ table_name	varchar(64)	NO		NULL
 column_name	varchar(64)	YES		NULL	
 data_type	longtext	YES		NULL	
 column_type	mediumtext	NO		NULL	
-is_signed	int unsigned	NO		0	
-is_unsigned	int unsigned	NO		0	
+is_signed	int	NO		0	
+is_unsigned	int	NO		0	
 max_value	bigint unsigned	YES		NULL	
 auto_increment	bigint unsigned	YES		NULL	
 auto_increment_ratio	decimal(25,4) unsigned	YES		NULL	

mysql-test/suite/test_service_sql_api/r/test_sql_complex.result

@@ -2884,7 +2884,7 @@ EXECUTING:[9][SELECT @a]
 			[meta][field] org col name: 
 			[meta][field] length: 21
 			[meta][field] charsetnr: 33
-			[meta][field] flags: 160 (UNSIGNED BINARY )
+			[meta][field] flags: 128 (BINARY )
 			[meta][field] decimals: 0
 			[meta][field] type: LONGLONG (8)
 
@@ -2916,7 +2916,7 @@ EXECUTING:[9][SELECT @a]
 			[meta][field] org col name: 
 			[meta][field] length: 21
 			[meta][field] charsetnr: 33
-			[meta][field] flags: 160 (UNSIGNED BINARY )
+			[meta][field] flags: 128 (BINARY )
 			[meta][field] decimals: 0
 			[meta][field] type: LONGLONG (8)
 
@@ -6093,7 +6093,7 @@ EXECUTING:[9][SELECT @a]
 			[meta][field] org col name: 
 			[meta][field] length: 21
 			[meta][field] charsetnr: 33
-			[meta][field] flags: 160 (UNSIGNED BINARY )
+			[meta][field] flags: 128 (BINARY )
 			[meta][field] decimals: 0
 			[meta][field] type: LONGLONG (8)
 
@@ -6125,7 +6125,7 @@ EXECUTING:[9][SELECT @a]
 			[meta][field] org col name: 
 			[meta][field] length: 21
 			[meta][field] charsetnr: 33
-			[meta][field] flags: 160 (UNSIGNED BINARY )
+			[meta][field] flags: 128 (BINARY )
 			[meta][field] decimals: 0
 			[meta][field] type: LONGLONG (8)
 

sql/item.h

@@ -1334,7 +1334,6 @@ class Item : public Parse_tree_node {
     set_data_type(MYSQL_TYPE_LONGLONG);
     collation.set_numeric();
     max_length = 1;
-    unsigned_flag = true;
   }
 
   /**

sql/item_func.cc

@@ -2658,6 +2658,8 @@ my_decimal *Item_func_neg::decimal_op(my_decimal *decimal_value) {
 void Item_func_neg::fix_num_length_and_dec() {
   decimals = args[0]->decimals;
   max_length = args[0]->max_length + (args[0]->unsigned_flag ? 1 : 0);
+  // Booleans have max_length = 1, but need to add the minus sign
+  if (max_length == 1) max_length++;
 }
 
 bool Item_func_neg::resolve_type(THD *thd) {