MDEV-23032 FLOOR()/CEIL() incorrectly calculate the precision of a DECIMAL(M,D) column

The code in Item_func_int_val::fix_length_and_dec_int_or_decimal()
calculated badly the result data type for FLOOR()/CEIL(), so for example
the decimal(38,10) input created a decimal(28,0) result.
That was not correct, because one extra integer digit is needed.
   floor(-9.9) -> -10
   ceil(9.9)   ->  10

Rewritting the code in a more straightforward way.
Additional changes:
- FLOOR() now takes into account the presence of the UNSIGNED
flag of the argument: FLOOR(unsigned decimal) does not need an extra digits.
- FLOOR()/CEILING() now preserve the unsigned flag in the result
  data type is decimal.
These changes give nicer data types.

11 files changed, 535 insertions, 156 deletions

diff --git a/mysql-test/include/ctype_numconv.inc b/mysql-test/include/ctype_numconv.inc
index 07298b1d47b..889c80cc477 100644
--- a/mysql-test/include/ctype_numconv.inc
+++ b/mysql-test/include/ctype_numconv.inc
@@ -194,12 +194,12 @@ show create table t1;
 drop table t1;
 
 select hex(concat(ceiling(0.5)));
-create table t1 as select concat(ceiling(0.5)) as c1;
+create table t1 as select ceiling(0.5) as c0, concat(ceiling(0.5)) as c1;
 show create table t1;
 drop table t1;
 
 select hex(concat(floor(0.5)));
-create table t1 as select concat(floor(0.5)) as c1;
+create table t1 as select floor(0.5) as c0, concat(floor(0.5)) as c1;
 show create table t1;
 drop table t1;
 
diff --git a/mysql-test/main/ctype_binary.result b/mysql-test/main/ctype_binary.result
index 931d295ec4a..97f970a9e49 100644
--- a/mysql-test/main/ctype_binary.result
+++ b/mysql-test/main/ctype_binary.result
@@ -348,21 +348,23 @@ drop table t1;
 select hex(concat(ceiling(0.5)));
 hex(concat(ceiling(0.5)))
 31
-create table t1 as select concat(ceiling(0.5)) as c1;
+create table t1 as select ceiling(0.5) as c0, concat(ceiling(0.5)) as c1;
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `c1` varbinary(4) DEFAULT NULL
+  `c0` int(3) NOT NULL,
+  `c1` varbinary(3) DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
 select hex(concat(floor(0.5)));
 hex(concat(floor(0.5)))
 30
-create table t1 as select concat(floor(0.5)) as c1;
+create table t1 as select floor(0.5) as c0, concat(floor(0.5)) as c1;
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `c1` varbinary(4) DEFAULT NULL
+  `c0` int(3) NOT NULL,
+  `c1` varbinary(3) DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
 select hex(concat(round(0.5)));
diff --git a/mysql-test/main/ctype_cp1251.result b/mysql-test/main/ctype_cp1251.result
index 03a0d413023..b0e6e1e6506 100644
--- a/mysql-test/main/ctype_cp1251.result
+++ b/mysql-test/main/ctype_cp1251.result
@@ -757,21 +757,23 @@ drop table t1;
 select hex(concat(ceiling(0.5)));
 hex(concat(ceiling(0.5)))
 31
-create table t1 as select concat(ceiling(0.5)) as c1;
+create table t1 as select ceiling(0.5) as c0, concat(ceiling(0.5)) as c1;
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `c1` varchar(4) CHARACTER SET cp1251 DEFAULT NULL
+  `c0` int(3) NOT NULL,
+  `c1` varchar(3) CHARACTER SET cp1251 DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
 select hex(concat(floor(0.5)));
 hex(concat(floor(0.5)))
 30
-create table t1 as select concat(floor(0.5)) as c1;
+create table t1 as select floor(0.5) as c0, concat(floor(0.5)) as c1;
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `c1` varchar(4) CHARACTER SET cp1251 DEFAULT NULL
+  `c0` int(3) NOT NULL,
+  `c1` varchar(3) CHARACTER SET cp1251 DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
 select hex(concat(round(0.5)));
diff --git a/mysql-test/main/ctype_latin1.result b/mysql-test/main/ctype_latin1.result
index a4925af69ae..b4005a4a73b 100644
--- a/mysql-test/main/ctype_latin1.result
+++ b/mysql-test/main/ctype_latin1.result
@@ -1066,21 +1066,23 @@ drop table t1;
 select hex(concat(ceiling(0.5)));
 hex(concat(ceiling(0.5)))
 31
-create table t1 as select concat(ceiling(0.5)) as c1;
+create table t1 as select ceiling(0.5) as c0, concat(ceiling(0.5)) as c1;
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `c1` varchar(4) DEFAULT NULL
+  `c0` int(3) NOT NULL,
+  `c1` varchar(3) DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
 select hex(concat(floor(0.5)));
 hex(concat(floor(0.5)))
 30
-create table t1 as select concat(floor(0.5)) as c1;
+create table t1 as select floor(0.5) as c0, concat(floor(0.5)) as c1;
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `c1` varchar(4) DEFAULT NULL
+  `c0` int(3) NOT NULL,
+  `c1` varchar(3) DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
 select hex(concat(round(0.5)));
diff --git a/mysql-test/main/ctype_ucs.result b/mysql-test/main/ctype_ucs.result
index fba779f5881..6292ad2591e 100644
--- a/mysql-test/main/ctype_ucs.result
+++ b/mysql-test/main/ctype_ucs.result
@@ -1950,21 +1950,23 @@ drop table t1;
 select hex(concat(ceiling(0.5)));
 hex(concat(ceiling(0.5)))
 0031
-create table t1 as select concat(ceiling(0.5)) as c1;
+create table t1 as select ceiling(0.5) as c0, concat(ceiling(0.5)) as c1;
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `c1` varchar(4) CHARACTER SET ucs2 DEFAULT NULL
+  `c0` int(3) NOT NULL,
+  `c1` varchar(3) CHARACTER SET ucs2 DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
 select hex(concat(floor(0.5)));
 hex(concat(floor(0.5)))
 0030
-create table t1 as select concat(floor(0.5)) as c1;
+create table t1 as select floor(0.5) as c0, concat(floor(0.5)) as c1;
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `c1` varchar(4) CHARACTER SET ucs2 DEFAULT NULL
+  `c0` int(3) NOT NULL,
+  `c1` varchar(3) CHARACTER SET ucs2 DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
 select hex(concat(round(0.5)));
diff --git a/mysql-test/main/ctype_utf8.result b/mysql-test/main/ctype_utf8.result
index 9585931584b..bd35fd10f19 100644
--- a/mysql-test/main/ctype_utf8.result
+++ b/mysql-test/main/ctype_utf8.result
@@ -2817,21 +2817,23 @@ drop table t1;
 select hex(concat(ceiling(0.5)));
 hex(concat(ceiling(0.5)))
 31
-create table t1 as select concat(ceiling(0.5)) as c1;
+create table t1 as select ceiling(0.5) as c0, concat(ceiling(0.5)) as c1;
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `c1` varchar(4) CHARACTER SET utf8 DEFAULT NULL
+  `c0` int(3) NOT NULL,
+  `c1` varchar(3) CHARACTER SET utf8 DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
 select hex(concat(floor(0.5)));
 hex(concat(floor(0.5)))
 30
-create table t1 as select concat(floor(0.5)) as c1;
+create table t1 as select floor(0.5) as c0, concat(floor(0.5)) as c1;
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `c1` varchar(4) CHARACTER SET utf8 DEFAULT NULL
+  `c0` int(3) NOT NULL,
+  `c1` varchar(3) CHARACTER SET utf8 DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
 select hex(concat(round(0.5)));
diff --git a/mysql-test/main/func_math.result b/mysql-test/main/func_math.result
index 163478f330c..a397f927265 100644
--- a/mysql-test/main/func_math.result
+++ b/mysql-test/main/func_math.result
@@ -1080,7 +1080,7 @@ Create Table	CREATE TABLE `t2` (
   `a` decimal(38,0) DEFAULT NULL,
   `b` decimal(38,0) unsigned DEFAULT NULL,
   `fa` decimal(38,0) DEFAULT NULL,
-  `fb` decimal(38,0) DEFAULT NULL
+  `fb` decimal(38,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999999999999999999999999999
 b	99999999999999999999999999999999999999
@@ -1090,8 +1090,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,1) DEFAULT NULL,
   `b` decimal(38,1) unsigned DEFAULT NULL,
-  `fa` decimal(37,0) DEFAULT NULL,
-  `fb` decimal(37,0) DEFAULT NULL
+  `fa` decimal(38,0) DEFAULT NULL,
+  `fb` decimal(37,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999999999999999999999999999.9
 b	9999999999999999999999999999999999999.9
@@ -1101,8 +1101,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,2) DEFAULT NULL,
   `b` decimal(38,2) unsigned DEFAULT NULL,
-  `fa` decimal(36,0) DEFAULT NULL,
-  `fb` decimal(36,0) DEFAULT NULL
+  `fa` decimal(37,0) DEFAULT NULL,
+  `fb` decimal(36,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999999999999999999999999999.99
 b	999999999999999999999999999999999999.99
@@ -1112,8 +1112,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,3) DEFAULT NULL,
   `b` decimal(38,3) unsigned DEFAULT NULL,
-  `fa` decimal(35,0) DEFAULT NULL,
-  `fb` decimal(35,0) DEFAULT NULL
+  `fa` decimal(36,0) DEFAULT NULL,
+  `fb` decimal(35,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999999999999999999999999.999
 b	99999999999999999999999999999999999.999
@@ -1123,8 +1123,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,4) DEFAULT NULL,
   `b` decimal(38,4) unsigned DEFAULT NULL,
-  `fa` decimal(34,0) DEFAULT NULL,
-  `fb` decimal(34,0) DEFAULT NULL
+  `fa` decimal(35,0) DEFAULT NULL,
+  `fb` decimal(34,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999999999999999999999999.9999
 b	9999999999999999999999999999999999.9999
@@ -1134,8 +1134,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,5) DEFAULT NULL,
   `b` decimal(38,5) unsigned DEFAULT NULL,
-  `fa` decimal(33,0) DEFAULT NULL,
-  `fb` decimal(33,0) DEFAULT NULL
+  `fa` decimal(34,0) DEFAULT NULL,
+  `fb` decimal(33,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999999999999999999999999.99999
 b	999999999999999999999999999999999.99999
@@ -1145,8 +1145,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,6) DEFAULT NULL,
   `b` decimal(38,6) unsigned DEFAULT NULL,
-  `fa` decimal(32,0) DEFAULT NULL,
-  `fb` decimal(32,0) DEFAULT NULL
+  `fa` decimal(33,0) DEFAULT NULL,
+  `fb` decimal(32,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999999999999999999999.999999
 b	99999999999999999999999999999999.999999
@@ -1156,8 +1156,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,7) DEFAULT NULL,
   `b` decimal(38,7) unsigned DEFAULT NULL,
-  `fa` decimal(31,0) DEFAULT NULL,
-  `fb` decimal(31,0) DEFAULT NULL
+  `fa` decimal(32,0) DEFAULT NULL,
+  `fb` decimal(31,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999999999999999999999.9999999
 b	9999999999999999999999999999999.9999999
@@ -1167,8 +1167,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,8) DEFAULT NULL,
   `b` decimal(38,8) unsigned DEFAULT NULL,
-  `fa` decimal(30,0) DEFAULT NULL,
-  `fb` decimal(30,0) DEFAULT NULL
+  `fa` decimal(31,0) DEFAULT NULL,
+  `fb` decimal(30,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999999999999999999999.99999999
 b	999999999999999999999999999999.99999999
@@ -1178,8 +1178,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,9) DEFAULT NULL,
   `b` decimal(38,9) unsigned DEFAULT NULL,
-  `fa` decimal(29,0) DEFAULT NULL,
-  `fb` decimal(29,0) DEFAULT NULL
+  `fa` decimal(30,0) DEFAULT NULL,
+  `fb` decimal(29,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999999999999999999.999999999
 b	99999999999999999999999999999.999999999
@@ -1189,8 +1189,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,10) DEFAULT NULL,
   `b` decimal(38,10) unsigned DEFAULT NULL,
-  `fa` decimal(28,0) DEFAULT NULL,
-  `fb` decimal(28,0) DEFAULT NULL
+  `fa` decimal(29,0) DEFAULT NULL,
+  `fb` decimal(28,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999999999999999999.9999999999
 b	9999999999999999999999999999.9999999999
@@ -1200,8 +1200,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,11) DEFAULT NULL,
   `b` decimal(38,11) unsigned DEFAULT NULL,
-  `fa` decimal(27,0) DEFAULT NULL,
-  `fb` decimal(27,0) DEFAULT NULL
+  `fa` decimal(28,0) DEFAULT NULL,
+  `fb` decimal(27,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999999999999999999.99999999999
 b	999999999999999999999999999.99999999999
@@ -1211,8 +1211,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,12) DEFAULT NULL,
   `b` decimal(38,12) unsigned DEFAULT NULL,
-  `fa` decimal(26,0) DEFAULT NULL,
-  `fb` decimal(26,0) DEFAULT NULL
+  `fa` decimal(27,0) DEFAULT NULL,
+  `fb` decimal(26,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999999999999999.999999999999
 b	99999999999999999999999999.999999999999
@@ -1222,8 +1222,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,13) DEFAULT NULL,
   `b` decimal(38,13) unsigned DEFAULT NULL,
-  `fa` decimal(25,0) DEFAULT NULL,
-  `fb` decimal(25,0) DEFAULT NULL
+  `fa` decimal(26,0) DEFAULT NULL,
+  `fb` decimal(25,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999999999999999.9999999999999
 b	9999999999999999999999999.9999999999999
@@ -1233,8 +1233,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,14) DEFAULT NULL,
   `b` decimal(38,14) unsigned DEFAULT NULL,
-  `fa` decimal(24,0) DEFAULT NULL,
-  `fb` decimal(24,0) DEFAULT NULL
+  `fa` decimal(25,0) DEFAULT NULL,
+  `fb` decimal(24,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999999999999999.99999999999999
 b	999999999999999999999999.99999999999999
@@ -1244,8 +1244,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,15) DEFAULT NULL,
   `b` decimal(38,15) unsigned DEFAULT NULL,
-  `fa` decimal(23,0) DEFAULT NULL,
-  `fb` decimal(23,0) DEFAULT NULL
+  `fa` decimal(24,0) DEFAULT NULL,
+  `fb` decimal(23,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999999999999.999999999999999
 b	99999999999999999999999.999999999999999
@@ -1255,8 +1255,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,16) DEFAULT NULL,
   `b` decimal(38,16) unsigned DEFAULT NULL,
-  `fa` decimal(22,0) DEFAULT NULL,
-  `fb` decimal(22,0) DEFAULT NULL
+  `fa` decimal(23,0) DEFAULT NULL,
+  `fb` decimal(22,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999999999999.9999999999999999
 b	9999999999999999999999.9999999999999999
@@ -1266,8 +1266,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,17) DEFAULT NULL,
   `b` decimal(38,17) unsigned DEFAULT NULL,
-  `fa` decimal(21,0) DEFAULT NULL,
-  `fb` decimal(21,0) DEFAULT NULL
+  `fa` decimal(22,0) DEFAULT NULL,
+  `fb` decimal(21,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999999999999.99999999999999999
 b	999999999999999999999.99999999999999999
@@ -1277,8 +1277,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,18) DEFAULT NULL,
   `b` decimal(38,18) unsigned DEFAULT NULL,
-  `fa` decimal(20,0) DEFAULT NULL,
-  `fb` decimal(20,0) DEFAULT NULL
+  `fa` decimal(21,0) DEFAULT NULL,
+  `fb` decimal(20,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999999999.999999999999999999
 b	99999999999999999999.999999999999999999
@@ -1288,8 +1288,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,19) DEFAULT NULL,
   `b` decimal(38,19) unsigned DEFAULT NULL,
-  `fa` decimal(19,0) DEFAULT NULL,
-  `fb` decimal(19,0) DEFAULT NULL
+  `fa` decimal(20,0) DEFAULT NULL,
+  `fb` decimal(19,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999999999.9999999999999999999
 b	9999999999999999999.9999999999999999999
@@ -1299,8 +1299,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,20) DEFAULT NULL,
   `b` decimal(38,20) unsigned DEFAULT NULL,
-  `fa` decimal(18,0) DEFAULT NULL,
-  `fb` bigint(17) unsigned DEFAULT NULL
+  `fa` decimal(19,0) DEFAULT NULL,
+  `fb` bigint(18) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999999999.99999999999999999999
 b	999999999999999999.99999999999999999999
@@ -1310,7 +1310,7 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,21) DEFAULT NULL,
   `b` decimal(38,21) unsigned DEFAULT NULL,
-  `fa` bigint(17) DEFAULT NULL,
+  `fa` bigint(19) DEFAULT NULL,
   `fb` bigint(17) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999999.999999999999999999999
@@ -1321,8 +1321,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,22) DEFAULT NULL,
   `b` decimal(38,22) unsigned DEFAULT NULL,
-  `fa` bigint(17) DEFAULT NULL,
-  `fb` bigint(17) unsigned DEFAULT NULL
+  `fa` bigint(18) DEFAULT NULL,
+  `fb` bigint(16) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999999.9999999999999999999999
 b	9999999999999999.9999999999999999999999
@@ -1333,7 +1333,7 @@ Create Table	CREATE TABLE `t2` (
   `a` decimal(38,23) DEFAULT NULL,
   `b` decimal(38,23) unsigned DEFAULT NULL,
   `fa` bigint(17) DEFAULT NULL,
-  `fb` bigint(17) unsigned DEFAULT NULL
+  `fb` bigint(15) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999999.99999999999999999999999
 b	999999999999999.99999999999999999999999
@@ -1343,8 +1343,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,24) DEFAULT NULL,
   `b` decimal(38,24) unsigned DEFAULT NULL,
-  `fa` bigint(17) DEFAULT NULL,
-  `fb` bigint(16) unsigned DEFAULT NULL
+  `fa` bigint(16) DEFAULT NULL,
+  `fb` bigint(14) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999.999999999999999999999999
 b	99999999999999.999999999999999999999999
@@ -1354,8 +1354,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,25) DEFAULT NULL,
   `b` decimal(38,25) unsigned DEFAULT NULL,
-  `fa` bigint(16) DEFAULT NULL,
-  `fb` bigint(15) unsigned DEFAULT NULL
+  `fa` bigint(15) DEFAULT NULL,
+  `fb` bigint(13) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999.9999999999999999999999999
 b	9999999999999.9999999999999999999999999
@@ -1365,8 +1365,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,26) DEFAULT NULL,
   `b` decimal(38,26) unsigned DEFAULT NULL,
-  `fa` bigint(15) DEFAULT NULL,
-  `fb` bigint(14) unsigned DEFAULT NULL
+  `fa` bigint(14) DEFAULT NULL,
+  `fb` bigint(12) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999.99999999999999999999999999
 b	999999999999.99999999999999999999999999
@@ -1376,8 +1376,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,27) DEFAULT NULL,
   `b` decimal(38,27) unsigned DEFAULT NULL,
-  `fa` bigint(14) DEFAULT NULL,
-  `fb` bigint(13) unsigned DEFAULT NULL
+  `fa` bigint(13) DEFAULT NULL,
+  `fb` bigint(11) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999.999999999999999999999999999
 b	99999999999.999999999999999999999999999
@@ -1387,8 +1387,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,28) DEFAULT NULL,
   `b` decimal(38,28) unsigned DEFAULT NULL,
-  `fa` bigint(13) DEFAULT NULL,
-  `fb` bigint(12) unsigned DEFAULT NULL
+  `fa` bigint(12) DEFAULT NULL,
+  `fb` bigint(10) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999.9999999999999999999999999999
 b	9999999999.9999999999999999999999999999
@@ -1398,8 +1398,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,29) DEFAULT NULL,
   `b` decimal(38,29) unsigned DEFAULT NULL,
-  `fa` bigint(12) DEFAULT NULL,
-  `fb` bigint(11) unsigned DEFAULT NULL
+  `fa` bigint(11) DEFAULT NULL,
+  `fb` int(9) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999.99999999999999999999999999999
 b	999999999.99999999999999999999999999999
@@ -1409,8 +1409,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(38,30) DEFAULT NULL,
   `b` decimal(38,30) unsigned DEFAULT NULL,
-  `fa` bigint(11) DEFAULT NULL,
-  `fb` bigint(10) unsigned DEFAULT NULL
+  `fa` int(10) DEFAULT NULL,
+  `fb` int(8) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999.999999999999999999999999999999
 b	99999999.999999999999999999999999999999
@@ -1422,7 +1422,7 @@ Create Table	CREATE TABLE `t2` (
   `a` decimal(30,0) DEFAULT NULL,
   `b` decimal(30,0) unsigned DEFAULT NULL,
   `fa` decimal(30,0) DEFAULT NULL,
-  `fb` decimal(31,0) unsigned DEFAULT NULL
+  `fb` decimal(30,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999999999999999999999
 b	999999999999999999999999999999
@@ -1432,8 +1432,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,1) DEFAULT NULL,
   `b` decimal(30,1) unsigned DEFAULT NULL,
-  `fa` decimal(29,0) DEFAULT NULL,
-  `fb` decimal(30,0) unsigned DEFAULT NULL
+  `fa` decimal(30,0) DEFAULT NULL,
+  `fb` decimal(29,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999999999999999999.9
 b	99999999999999999999999999999.9
@@ -1443,8 +1443,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,2) DEFAULT NULL,
   `b` decimal(30,2) unsigned DEFAULT NULL,
-  `fa` decimal(28,0) DEFAULT NULL,
-  `fb` decimal(29,0) unsigned DEFAULT NULL
+  `fa` decimal(29,0) DEFAULT NULL,
+  `fb` decimal(28,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999999999999999999.99
 b	9999999999999999999999999999.99
@@ -1454,8 +1454,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,3) DEFAULT NULL,
   `b` decimal(30,3) unsigned DEFAULT NULL,
-  `fa` decimal(27,0) DEFAULT NULL,
-  `fb` decimal(28,0) unsigned DEFAULT NULL
+  `fa` decimal(28,0) DEFAULT NULL,
+  `fb` decimal(27,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999999999999999999.999
 b	999999999999999999999999999.999
@@ -1465,8 +1465,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,4) DEFAULT NULL,
   `b` decimal(30,4) unsigned DEFAULT NULL,
-  `fa` decimal(26,0) DEFAULT NULL,
-  `fb` decimal(27,0) unsigned DEFAULT NULL
+  `fa` decimal(27,0) DEFAULT NULL,
+  `fb` decimal(26,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999999999999999.9999
 b	99999999999999999999999999.9999
@@ -1476,8 +1476,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,5) DEFAULT NULL,
   `b` decimal(30,5) unsigned DEFAULT NULL,
-  `fa` decimal(25,0) DEFAULT NULL,
-  `fb` decimal(26,0) unsigned DEFAULT NULL
+  `fa` decimal(26,0) DEFAULT NULL,
+  `fb` decimal(25,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999999999999999.99999
 b	9999999999999999999999999.99999
@@ -1487,8 +1487,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,6) DEFAULT NULL,
   `b` decimal(30,6) unsigned DEFAULT NULL,
-  `fa` decimal(24,0) DEFAULT NULL,
-  `fb` decimal(25,0) unsigned DEFAULT NULL
+  `fa` decimal(25,0) DEFAULT NULL,
+  `fb` decimal(24,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999999999999999.999999
 b	999999999999999999999999.999999
@@ -1498,8 +1498,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,7) DEFAULT NULL,
   `b` decimal(30,7) unsigned DEFAULT NULL,
-  `fa` decimal(23,0) DEFAULT NULL,
-  `fb` decimal(24,0) unsigned DEFAULT NULL
+  `fa` decimal(24,0) DEFAULT NULL,
+  `fb` decimal(23,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999999999999.9999999
 b	99999999999999999999999.9999999
@@ -1509,8 +1509,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,8) DEFAULT NULL,
   `b` decimal(30,8) unsigned DEFAULT NULL,
-  `fa` decimal(22,0) DEFAULT NULL,
-  `fb` decimal(23,0) unsigned DEFAULT NULL
+  `fa` decimal(23,0) DEFAULT NULL,
+  `fb` decimal(22,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999999999999.99999999
 b	9999999999999999999999.99999999
@@ -1520,8 +1520,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,9) DEFAULT NULL,
   `b` decimal(30,9) unsigned DEFAULT NULL,
-  `fa` decimal(21,0) DEFAULT NULL,
-  `fb` decimal(22,0) unsigned DEFAULT NULL
+  `fa` decimal(22,0) DEFAULT NULL,
+  `fb` decimal(21,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999999999999.999999999
 b	999999999999999999999.999999999
@@ -1531,8 +1531,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,10) DEFAULT NULL,
   `b` decimal(30,10) unsigned DEFAULT NULL,
-  `fa` decimal(20,0) DEFAULT NULL,
-  `fb` decimal(21,0) unsigned DEFAULT NULL
+  `fa` decimal(21,0) DEFAULT NULL,
+  `fb` decimal(20,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999999999.9999999999
 b	99999999999999999999.9999999999
@@ -1542,8 +1542,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,11) DEFAULT NULL,
   `b` decimal(30,11) unsigned DEFAULT NULL,
-  `fa` decimal(19,0) DEFAULT NULL,
-  `fb` decimal(20,0) unsigned DEFAULT NULL
+  `fa` decimal(20,0) DEFAULT NULL,
+  `fb` decimal(19,0) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999999999.99999999999
 b	9999999999999999999.99999999999
@@ -1553,8 +1553,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,12) DEFAULT NULL,
   `b` decimal(30,12) unsigned DEFAULT NULL,
-  `fa` decimal(18,0) DEFAULT NULL,
-  `fb` bigint(17) unsigned DEFAULT NULL
+  `fa` decimal(19,0) DEFAULT NULL,
+  `fb` bigint(18) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999999999.999999999999
 b	999999999999999999.999999999999
@@ -1564,7 +1564,7 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,13) DEFAULT NULL,
   `b` decimal(30,13) unsigned DEFAULT NULL,
-  `fa` bigint(17) DEFAULT NULL,
+  `fa` bigint(19) DEFAULT NULL,
   `fb` bigint(17) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999999.9999999999999
@@ -1575,8 +1575,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,14) DEFAULT NULL,
   `b` decimal(30,14) unsigned DEFAULT NULL,
-  `fa` bigint(17) DEFAULT NULL,
-  `fb` bigint(17) unsigned DEFAULT NULL
+  `fa` bigint(18) DEFAULT NULL,
+  `fb` bigint(16) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999999.99999999999999
 b	9999999999999999.99999999999999
@@ -1587,7 +1587,7 @@ Create Table	CREATE TABLE `t2` (
   `a` decimal(30,15) DEFAULT NULL,
   `b` decimal(30,15) unsigned DEFAULT NULL,
   `fa` bigint(17) DEFAULT NULL,
-  `fb` bigint(17) unsigned DEFAULT NULL
+  `fb` bigint(15) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999999.999999999999999
 b	999999999999999.999999999999999
@@ -1597,8 +1597,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,16) DEFAULT NULL,
   `b` decimal(30,16) unsigned DEFAULT NULL,
-  `fa` bigint(17) DEFAULT NULL,
-  `fb` bigint(16) unsigned DEFAULT NULL
+  `fa` bigint(16) DEFAULT NULL,
+  `fb` bigint(14) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999999.9999999999999999
 b	99999999999999.9999999999999999
@@ -1608,8 +1608,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,17) DEFAULT NULL,
   `b` decimal(30,17) unsigned DEFAULT NULL,
-  `fa` bigint(16) DEFAULT NULL,
-  `fb` bigint(15) unsigned DEFAULT NULL
+  `fa` bigint(15) DEFAULT NULL,
+  `fb` bigint(13) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999999.99999999999999999
 b	9999999999999.99999999999999999
@@ -1619,8 +1619,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,18) DEFAULT NULL,
   `b` decimal(30,18) unsigned DEFAULT NULL,
-  `fa` bigint(15) DEFAULT NULL,
-  `fb` bigint(14) unsigned DEFAULT NULL
+  `fa` bigint(14) DEFAULT NULL,
+  `fb` bigint(12) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999999.999999999999999999
 b	999999999999.999999999999999999
@@ -1630,8 +1630,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,19) DEFAULT NULL,
   `b` decimal(30,19) unsigned DEFAULT NULL,
-  `fa` bigint(14) DEFAULT NULL,
-  `fb` bigint(13) unsigned DEFAULT NULL
+  `fa` bigint(13) DEFAULT NULL,
+  `fb` bigint(11) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999999.9999999999999999999
 b	99999999999.9999999999999999999
@@ -1641,8 +1641,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,20) DEFAULT NULL,
   `b` decimal(30,20) unsigned DEFAULT NULL,
-  `fa` bigint(13) DEFAULT NULL,
-  `fb` bigint(12) unsigned DEFAULT NULL
+  `fa` bigint(12) DEFAULT NULL,
+  `fb` bigint(10) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999999.99999999999999999999
 b	9999999999.99999999999999999999
@@ -1652,8 +1652,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,21) DEFAULT NULL,
   `b` decimal(30,21) unsigned DEFAULT NULL,
-  `fa` bigint(12) DEFAULT NULL,
-  `fb` bigint(11) unsigned DEFAULT NULL
+  `fa` bigint(11) DEFAULT NULL,
+  `fb` int(9) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999999.999999999999999999999
 b	999999999.999999999999999999999
@@ -1663,8 +1663,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,22) DEFAULT NULL,
   `b` decimal(30,22) unsigned DEFAULT NULL,
-  `fa` bigint(11) DEFAULT NULL,
-  `fb` bigint(10) unsigned DEFAULT NULL
+  `fa` int(10) DEFAULT NULL,
+  `fb` int(8) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999999.9999999999999999999999
 b	99999999.9999999999999999999999
@@ -1674,8 +1674,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,23) DEFAULT NULL,
   `b` decimal(30,23) unsigned DEFAULT NULL,
-  `fa` bigint(10) DEFAULT NULL,
-  `fb` int(9) unsigned DEFAULT NULL
+  `fa` int(9) DEFAULT NULL,
+  `fb` int(7) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999999.99999999999999999999999
 b	9999999.99999999999999999999999
@@ -1685,8 +1685,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,24) DEFAULT NULL,
   `b` decimal(30,24) unsigned DEFAULT NULL,
-  `fa` int(9) DEFAULT NULL,
-  `fb` int(8) unsigned DEFAULT NULL
+  `fa` int(8) DEFAULT NULL,
+  `fb` int(6) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999999.999999999999999999999999
 b	999999.999999999999999999999999
@@ -1696,8 +1696,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,25) DEFAULT NULL,
   `b` decimal(30,25) unsigned DEFAULT NULL,
-  `fa` int(8) DEFAULT NULL,
-  `fb` int(7) unsigned DEFAULT NULL
+  `fa` int(7) DEFAULT NULL,
+  `fb` int(5) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99999.9999999999999999999999999
 b	99999.9999999999999999999999999
@@ -1707,8 +1707,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,26) DEFAULT NULL,
   `b` decimal(30,26) unsigned DEFAULT NULL,
-  `fa` int(7) DEFAULT NULL,
-  `fb` int(6) unsigned DEFAULT NULL
+  `fa` int(6) DEFAULT NULL,
+  `fb` int(4) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9999.99999999999999999999999999
 b	9999.99999999999999999999999999
@@ -1718,8 +1718,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,27) DEFAULT NULL,
   `b` decimal(30,27) unsigned DEFAULT NULL,
-  `fa` int(6) DEFAULT NULL,
-  `fb` int(5) unsigned DEFAULT NULL
+  `fa` int(5) DEFAULT NULL,
+  `fb` int(3) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	999.999999999999999999999999999
 b	999.999999999999999999999999999
@@ -1729,8 +1729,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,28) DEFAULT NULL,
   `b` decimal(30,28) unsigned DEFAULT NULL,
-  `fa` int(5) DEFAULT NULL,
-  `fb` int(4) unsigned DEFAULT NULL
+  `fa` int(4) DEFAULT NULL,
+  `fb` int(2) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	99.9999999999999999999999999999
 b	99.9999999999999999999999999999
@@ -1740,8 +1740,8 @@ Table	t2
 Create Table	CREATE TABLE `t2` (
   `a` decimal(30,29) DEFAULT NULL,
   `b` decimal(30,29) unsigned DEFAULT NULL,
-  `fa` int(4) DEFAULT NULL,
-  `fb` int(3) unsigned DEFAULT NULL
+  `fa` int(3) DEFAULT NULL,
+  `fb` int(1) unsigned DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 a	9.99999999999999999999999999999
 b	9.99999999999999999999999999999
diff --git a/mysql-test/main/type_newdecimal.result b/mysql-test/main/type_newdecimal.result
index d5fc6db107b..0a631521d49 100644
--- a/mysql-test/main/type_newdecimal.result
+++ b/mysql-test/main/type_newdecimal.result
@@ -2411,3 +2411,292 @@ drop table t1;
 #
 # End of 10.2 tests
 #
+#
+# Start of 10.4 tests
+#
+#
+# MDEV-23032 FLOOR()/CEIL() incorrectly calculate the precision of a DECIMAL(M,D) column.
+#
+CREATE PROCEDURE p1(prec INT, scale INT, suffix VARCHAR(32))
+BEGIN
+EXECUTE IMMEDIATE CONCAT('CREATE TABLE t1 (a decimal(',prec,',',scale,')',suffix,')');
+INSERT IGNORE INTO t1 VALUES (-1e100), (+1e100);
+CREATE TABLE t2 AS SELECT
+a,
+FLOOR(a) AS fa,
+CEILING(a) AS ca,
+LENGTH(FLOOR(a)),
+LENGTH(CEILING(a))
+FROM t1 ORDER BY a;
+SHOW CREATE TABLE t2;
+SELECT * FROM t2;
+DROP TABLE t2, t1;
+END;
+$$
+CALL p1(38,10,'');
+Table	t2
+Create Table	CREATE TABLE `t2` (
+  `a` decimal(38,10) DEFAULT NULL,
+  `fa` decimal(29,0) DEFAULT NULL,
+  `ca` decimal(29,0) DEFAULT NULL,
+  `LENGTH(FLOOR(a))` int(10) DEFAULT NULL,
+  `LENGTH(CEILING(a))` int(10) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+a	-9999999999999999999999999999.9999999999
+fa	-10000000000000000000000000000
+ca	-9999999999999999999999999999
+LENGTH(FLOOR(a))	30
+LENGTH(CEILING(a))	29
+a	9999999999999999999999999999.9999999999
+fa	9999999999999999999999999999
+ca	10000000000000000000000000000
+LENGTH(FLOOR(a))	28
+LENGTH(CEILING(a))	29
+CALL p1(28,10,'');
+Table	t2
+Create Table	CREATE TABLE `t2` (
+  `a` decimal(28,10) DEFAULT NULL,
+  `fa` decimal(19,0) DEFAULT NULL,
+  `ca` decimal(19,0) DEFAULT NULL,
+  `LENGTH(FLOOR(a))` int(10) DEFAULT NULL,
+  `LENGTH(CEILING(a))` int(10) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+a	-999999999999999999.9999999999
+fa	-1000000000000000000
+ca	-999999999999999999
+LENGTH(FLOOR(a))	20
+LENGTH(CEILING(a))	19
+a	999999999999999999.9999999999
+fa	999999999999999999
+ca	1000000000000000000
+LENGTH(FLOOR(a))	18
+LENGTH(CEILING(a))	19
+CALL p1(27,10,'');
+Table	t2
+Create Table	CREATE TABLE `t2` (
+  `a` decimal(27,10) DEFAULT NULL,
+  `fa` bigint(19) DEFAULT NULL,
+  `ca` bigint(19) DEFAULT NULL,
+  `LENGTH(FLOOR(a))` int(10) DEFAULT NULL,
+  `LENGTH(CEILING(a))` int(10) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+a	-99999999999999999.9999999999
+fa	-100000000000000000
+ca	-99999999999999999
+LENGTH(FLOOR(a))	19
+LENGTH(CEILING(a))	18
+a	99999999999999999.9999999999
+fa	99999999999999999
+ca	100000000000000000
+LENGTH(FLOOR(a))	17
+LENGTH(CEILING(a))	18
+CALL p1(20,10,'');
+Table	t2
+Create Table	CREATE TABLE `t2` (
+  `a` decimal(20,10) DEFAULT NULL,
+  `fa` bigint(12) DEFAULT NULL,
+  `ca` bigint(12) DEFAULT NULL,
+  `LENGTH(FLOOR(a))` int(10) DEFAULT NULL,
+  `LENGTH(CEILING(a))` int(10) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+a	-9999999999.9999999999
+fa	-10000000000
+ca	-9999999999
+LENGTH(FLOOR(a))	12
+LENGTH(CEILING(a))	11
+a	9999999999.9999999999
+fa	9999999999
+ca	10000000000
+LENGTH(FLOOR(a))	10
+LENGTH(CEILING(a))	11
+CALL p1(19,10,'');
+Table	t2
+Create Table	CREATE TABLE `t2` (
+  `a` decimal(19,10) DEFAULT NULL,
+  `fa` bigint(11) DEFAULT NULL,
+  `ca` bigint(11) DEFAULT NULL,
+  `LENGTH(FLOOR(a))` int(10) DEFAULT NULL,
+  `LENGTH(CEILING(a))` int(10) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+a	-999999999.9999999999
+fa	-1000000000
+ca	-999999999
+LENGTH(FLOOR(a))	11
+LENGTH(CEILING(a))	10
+a	999999999.9999999999
+fa	999999999
+ca	1000000000
+LENGTH(FLOOR(a))	9
+LENGTH(CEILING(a))	10
+CALL p1(18,10,'');
+Table	t2
+Create Table	CREATE TABLE `t2` (
+  `a` decimal(18,10) DEFAULT NULL,
+  `fa` int(10) DEFAULT NULL,
+  `ca` int(10) DEFAULT NULL,
+  `LENGTH(FLOOR(a))` int(10) DEFAULT NULL,
+  `LENGTH(CEILING(a))` int(10) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+a	-99999999.9999999999
+fa	-100000000
+ca	-99999999
+LENGTH(FLOOR(a))	10
+LENGTH(CEILING(a))	9
+a	99999999.9999999999
+fa	99999999
+ca	100000000
+LENGTH(FLOOR(a))	8
+LENGTH(CEILING(a))	9
+CALL p1(10,10,'');
+Table	t2
+Create Table	CREATE TABLE `t2` (
+  `a` decimal(10,10) DEFAULT NULL,
+  `fa` int(2) DEFAULT NULL,
+  `ca` int(2) DEFAULT NULL,
+  `LENGTH(FLOOR(a))` int(10) DEFAULT NULL,
+  `LENGTH(CEILING(a))` int(10) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+a	-0.9999999999
+fa	-1
+ca	0
+LENGTH(FLOOR(a))	2
+LENGTH(CEILING(a))	1
+a	0.9999999999
+fa	0
+ca	1
+LENGTH(FLOOR(a))	1
+LENGTH(CEILING(a))	1
+CALL p1(38,10,'  UNSIGNED');
+Table	t2
+Create Table	CREATE TABLE `t2` (
+  `a` decimal(38,10) unsigned DEFAULT NULL,
+  `fa` decimal(28,0) unsigned DEFAULT NULL,
+  `ca` decimal(29,0) unsigned DEFAULT NULL,
+  `LENGTH(FLOOR(a))` int(10) DEFAULT NULL,
+  `LENGTH(CEILING(a))` int(10) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+a	0.0000000000
+fa	0
+ca	0
+LENGTH(FLOOR(a))	1
+LENGTH(CEILING(a))	1
+a	9999999999999999999999999999.9999999999
+fa	9999999999999999999999999999
+ca	10000000000000000000000000000
+LENGTH(FLOOR(a))	28
+LENGTH(CEILING(a))	29
+CALL p1(28,10,'  UNSIGNED');
+Table	t2
+Create Table	CREATE TABLE `t2` (
+  `a` decimal(28,10) unsigned DEFAULT NULL,
+  `fa` bigint(18) unsigned DEFAULT NULL,
+  `ca` decimal(19,0) unsigned DEFAULT NULL,
+  `LENGTH(FLOOR(a))` int(10) DEFAULT NULL,
+  `LENGTH(CEILING(a))` int(10) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+a	0.0000000000
+fa	0
+ca	0
+LENGTH(FLOOR(a))	1
+LENGTH(CEILING(a))	1
+a	999999999999999999.9999999999
+fa	999999999999999999
+ca	1000000000000000000
+LENGTH(FLOOR(a))	18
+LENGTH(CEILING(a))	19
+CALL p1(27,10,'  UNSIGNED');
+Table	t2
+Create Table	CREATE TABLE `t2` (
+  `a` decimal(27,10) unsigned DEFAULT NULL,
+  `fa` bigint(17) unsigned DEFAULT NULL,
+  `ca` bigint(18) unsigned DEFAULT NULL,
+  `LENGTH(FLOOR(a))` int(10) DEFAULT NULL,
+  `LENGTH(CEILING(a))` int(10) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+a	0.0000000000
+fa	0
+ca	0
+LENGTH(FLOOR(a))	1
+LENGTH(CEILING(a))	1
+a	99999999999999999.9999999999
+fa	99999999999999999
+ca	100000000000000000
+LENGTH(FLOOR(a))	17
+LENGTH(CEILING(a))	18
+CALL p1(20,10,'  UNSIGNED');
+Table	t2
+Create Table	CREATE TABLE `t2` (
+  `a` decimal(20,10) unsigned DEFAULT NULL,
+  `fa` bigint(10) unsigned DEFAULT NULL,
+  `ca` bigint(11) unsigned DEFAULT NULL,
+  `LENGTH(FLOOR(a))` int(10) DEFAULT NULL,
+  `LENGTH(CEILING(a))` int(10) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+a	0.0000000000
+fa	0
+ca	0
+LENGTH(FLOOR(a))	1
+LENGTH(CEILING(a))	1
+a	9999999999.9999999999
+fa	9999999999
+ca	10000000000
+LENGTH(FLOOR(a))	10
+LENGTH(CEILING(a))	11
+CALL p1(19,10,'  UNSIGNED');
+Table	t2
+Create Table	CREATE TABLE `t2` (
+  `a` decimal(19,10) unsigned DEFAULT NULL,
+  `fa` int(9) unsigned DEFAULT NULL,
+  `ca` bigint(10) unsigned DEFAULT NULL,
+  `LENGTH(FLOOR(a))` int(10) DEFAULT NULL,
+  `LENGTH(CEILING(a))` int(10) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+a	0.0000000000
+fa	0
+ca	0
+LENGTH(FLOOR(a))	1
+LENGTH(CEILING(a))	1
+a	999999999.9999999999
+fa	999999999
+ca	1000000000
+LENGTH(FLOOR(a))	9
+LENGTH(CEILING(a))	10
+CALL p1(18,10,'  UNSIGNED');
+Table	t2
+Create Table	CREATE TABLE `t2` (
+  `a` decimal(18,10) unsigned DEFAULT NULL,
+  `fa` int(8) unsigned DEFAULT NULL,
+  `ca` int(9) unsigned DEFAULT NULL,
+  `LENGTH(FLOOR(a))` int(10) DEFAULT NULL,
+  `LENGTH(CEILING(a))` int(10) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+a	0.0000000000
+fa	0
+ca	0
+LENGTH(FLOOR(a))	1
+LENGTH(CEILING(a))	1
+a	99999999.9999999999
+fa	99999999
+ca	100000000
+LENGTH(FLOOR(a))	8
+LENGTH(CEILING(a))	9
+CALL p1(10,10,'  UNSIGNED');
+Table	t2
+Create Table	CREATE TABLE `t2` (
+  `a` decimal(10,10) unsigned DEFAULT NULL,
+  `fa` int(1) unsigned DEFAULT NULL,
+  `ca` int(1) unsigned DEFAULT NULL,
+  `LENGTH(FLOOR(a))` int(10) DEFAULT NULL,
+  `LENGTH(CEILING(a))` int(10) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+a	0.0000000000
+fa	0
+ca	0
+LENGTH(FLOOR(a))	1
+LENGTH(CEILING(a))	1
+a	0.9999999999
+fa	0
+ca	1
+LENGTH(FLOOR(a))	1
+LENGTH(CEILING(a))	1
+DROP PROCEDURE p1;
diff --git a/mysql-test/main/type_newdecimal.test b/mysql-test/main/type_newdecimal.test
index 2f3409f56e9..7cf0a486268 100644
--- a/mysql-test/main/type_newdecimal.test
+++ b/mysql-test/main/type_newdecimal.test
@@ -1871,3 +1871,51 @@ drop table t1;
 --echo #
 --echo # End of 10.2 tests
 --echo #
+
+--echo #
+--echo # Start of 10.4 tests
+--echo #
+
+--echo #
+--echo # MDEV-23032 FLOOR()/CEIL() incorrectly calculate the precision of a DECIMAL(M,D) column.
+--echo #
+
+DELIMITER $$;
+CREATE PROCEDURE p1(prec INT, scale INT, suffix VARCHAR(32))
+BEGIN
+  EXECUTE IMMEDIATE CONCAT('CREATE TABLE t1 (a decimal(',prec,',',scale,')',suffix,')');
+  INSERT IGNORE INTO t1 VALUES (-1e100), (+1e100);
+  CREATE TABLE t2 AS SELECT
+    a,
+    FLOOR(a) AS fa,
+    CEILING(a) AS ca,
+    LENGTH(FLOOR(a)),
+    LENGTH(CEILING(a))
+  FROM t1 ORDER BY a;
+  SHOW CREATE TABLE t2;
+  SELECT * FROM t2;
+  DROP TABLE t2, t1;
+END;
+$$
+DELIMITER ;$$
+
+--vertical_results
+CALL p1(38,10,'');
+CALL p1(28,10,'');
+CALL p1(27,10,'');
+CALL p1(20,10,'');
+CALL p1(19,10,'');
+CALL p1(18,10,'');
+CALL p1(10,10,'');
+
+CALL p1(38,10,'  UNSIGNED');
+CALL p1(28,10,'  UNSIGNED');
+CALL p1(27,10,'  UNSIGNED');
+CALL p1(20,10,'  UNSIGNED');
+CALL p1(19,10,'  UNSIGNED');
+CALL p1(18,10,'  UNSIGNED');
+CALL p1(10,10,'  UNSIGNED');
+
+--horizontal_results
+
+DROP PROCEDURE p1;
diff --git a/sql/item_func.cc b/sql/item_func.cc
index 8000d7f6a1d..e4f9e8f164a 100644
--- a/sql/item_func.cc
+++ b/sql/item_func.cc
@@ -2173,35 +2173,64 @@ longlong Item_func_bit_neg::val_int()
 
 void Item_func_int_val::fix_length_and_dec_int_or_decimal()
 {
+  DBUG_ASSERT(args[0]->cmp_type() == DECIMAL_RESULT);
+  DBUG_ASSERT(args[0]->max_length <= DECIMAL_MAX_STR_LENGTH);
   /*
-    The INT branch of this code should be revised.
-    It creates too large data types, e.g.
-      CREATE OR REPLACE TABLE t2 AS SELECT FLOOR(9999999.999) AS fa;
-    results in a BININT(10) column, while INT(7) should probably be enough.
+    FLOOR() for negative numbers can increase length:   floor(-9.9) -> -10
+    CEILING() for positive numbers can increase length:  ceil(9.9)  -> 10
   */
-  ulonglong tmp_max_length= (ulonglong ) args[0]->max_length - 
-    (args[0]->decimals ? args[0]->decimals + 1 : 0) + 2;
-  max_length= tmp_max_length > (ulonglong) UINT_MAX32 ?
-    (uint32) UINT_MAX32 : (uint32) tmp_max_length;
-  uint tmp= float_length(decimals);
-  set_if_smaller(max_length,tmp);
-  decimals= 0;
+  decimal_round_mode mode= round_mode();
+  uint length_increase= args[0]->decimals > 0 &&
+                        (mode == CEILING ||
+                         (mode == FLOOR && !args[0]->unsigned_flag)) ? 1 : 0;
+  uint precision= args[0]->decimal_int_part() + length_increase;
+  set_if_bigger(precision, 1);
 
   /*
-    -2 because in most high position can't be used any digit for longlong
-    and one position for increasing value during operation
+    The BIGINT data type can store:
+    UNSIGNED BIGINT: 0..18446744073709551615                     - up to 19 digits
+      SIGNED BIGINT:   -9223372036854775808..9223372036854775807 - up to 18 digits
+
+    The INT data type can store:
+        UNSIGNED INT:  0..4294967295          - up to 9 digits
+          SIGNED INT: -2147483648..2147483647 - up to 9 digits
   */
-  if (args[0]->max_length - args[0]->decimals >= DECIMAL_LONGLONG_DIGITS - 2)
+  if (precision > 18)
   {
+    unsigned_flag= args[0]->unsigned_flag;
     fix_char_length(
-      my_decimal_precision_to_length_no_truncation(
-        args[0]->decimal_int_part(), 0, false));
+      my_decimal_precision_to_length_no_truncation(precision, 0,
+                                                   unsigned_flag));
     set_handler(&type_handler_newdecimal);
   }
   else
   {
-    unsigned_flag= args[0]->unsigned_flag;
-    set_handler(type_handler_long_or_longlong());
+    uint sign_length= (unsigned_flag= args[0]->unsigned_flag) ? 0 : 1;
+    fix_char_length(precision + sign_length);
+    if (precision > 9)
+    {
+#if MYSQL_VERSION_ID > 100500
+#error Remove the '#else' branch and the conditional compilation
+      if (unsigned_flag)
+        set_handler(&type_handler_ulonglong);
+      else
+        set_handler(&type_handler_slonglong);
+#else
+      set_handler(&type_handler_longlong);
+#endif
+    }
+    else
+    {
+#if MYSQL_VERSION_ID > 100500
+#error Remove the '#else' branch and the conditional compilation
+      if (unsigned_flag)
+        set_handler(&type_handler_ulong);
+      else
+        set_handler(&type_handler_slong);
+#else
+      set_handler(&type_handler_long);
+#endif
+    }
   }
 }
 
diff --git a/sql/item_func.h b/sql/item_func.h
index 24601983f86..d1292c3e07a 100644
--- a/sql/item_func.h
+++ b/sql/item_func.h
@@ -1695,6 +1695,7 @@ public:
   Item_func_int_val(THD *thd, Item *a): Item_func_hybrid_field_type(thd, a) {}
   bool check_partition_func_processor(void *int_arg) { return FALSE; }
   bool check_vcol_func_processor(void *arg) { return FALSE; }
+  virtual decimal_round_mode round_mode() const= 0;
   void fix_length_and_dec_double();
   void fix_length_and_dec_int_or_decimal();
   void fix_length_and_dec_time()
@@ -1723,6 +1724,7 @@ class Item_func_ceiling :public Item_func_int_val
 public:
   Item_func_ceiling(THD *thd, Item *a): Item_func_int_val(thd, a) {}
   const char *func_name() const { return "ceiling"; }
+  decimal_round_mode round_mode() const { return CEILING; }
   longlong int_op();
   double real_op();
   my_decimal *decimal_op(my_decimal *);
@@ -1738,6 +1740,7 @@ class Item_func_floor :public Item_func_int_val
 public:
   Item_func_floor(THD *thd, Item *a): Item_func_int_val(thd, a) {}
   const char *func_name() const { return "floor"; }
+  decimal_round_mode round_mode() const { return FLOOR; }
   longlong int_op();
   double real_op();
   my_decimal *decimal_op(my_decimal *);