Commit 2c65a31a authored by Staale Smedseng's avatar Staale Smedseng

Merge from 5.0-bugteam

parents 50ed1ef7 dcac05be
......@@ -1506,4 +1506,16 @@ DESC t6;
Field Type Null Key Default Extra
NULL int(11) YES NULL
DROP TABLE t1, t2, t3, t4, t5, t6;
CREATE TABLE t1 (f FLOAT(9,6));
CREATE TABLE t2 AS SELECT f FROM t1 UNION SELECT f FROM t1;
SHOW FIELDS FROM t2;
Field Type Null Key Default Extra
f float(9,6) YES NULL
DROP TABLE t1, t2;
CREATE TABLE t1(d DOUBLE(9,6));
CREATE TABLE t2 AS SELECT d FROM t1 UNION SELECT d FROM t1;
SHOW FIELDS FROM t2;
Field Type Null Key Default Extra
d double(9,6) YES NULL
DROP TABLE t1, t2;
End of 5.0 tests
......@@ -1023,4 +1023,19 @@ SELECT * FROM (SELECT * FROM (SELECT NULL)a) b UNION SELECT a FROM t1;
DESC t6;
DROP TABLE t1, t2, t3, t4, t5, t6;
#
# Bug #43432: Union on floats does unnecessary rounding
#
CREATE TABLE t1 (f FLOAT(9,6));
CREATE TABLE t2 AS SELECT f FROM t1 UNION SELECT f FROM t1;
SHOW FIELDS FROM t2;
DROP TABLE t1, t2;
CREATE TABLE t1(d DOUBLE(9,6));
CREATE TABLE t2 AS SELECT d FROM t1 UNION SELECT d FROM t1;
SHOW FIELDS FROM t2;
DROP TABLE t1, t2;
--echo End of 5.0 tests
......@@ -8587,16 +8587,16 @@ bool create_field::init(THD *thd, char *fld_name, enum_field_types fld_type,
else if (tmp_length > PRECISION_FOR_FLOAT)
{
sql_type= FIELD_TYPE_DOUBLE;
length= DBL_DIG+7; /* -[digits].E+### */
length= MAX_DOUBLE_STR_LENGTH;
}
else
length= FLT_DIG+6; /* -[digits].E+## */
length= MAX_FLOAT_STR_LENGTH;
decimals= NOT_FIXED_DEC;
break;
}
if (!fld_length && !fld_decimals)
{
length= FLT_DIG+6;
length= MAX_FLOAT_STR_LENGTH;
decimals= NOT_FIXED_DEC;
}
if (length < decimals &&
......
......@@ -6968,21 +6968,29 @@ bool Item_type_holder::join_types(THD *thd, Item *item)
case REAL_RESULT:
{
if (decimals != NOT_FIXED_DEC)
{
/*
For FLOAT(M,D)/DOUBLE(M,D) do not change precision
if both fields have the same M and D
*/
if (item->max_length != max_length_orig ||
item->decimals != decimals_orig)
{
int delta1= max_length_orig - decimals_orig;
int delta2= item->max_length - item->decimals;
max_length= max(delta1, delta2) + decimals;
if (fld_type == MYSQL_TYPE_FLOAT && max_length > FLT_DIG + 2)
{
max_length= FLT_DIG + 6;
max_length= MAX_FLOAT_STR_LENGTH;
decimals= NOT_FIXED_DEC;
}
if (fld_type == MYSQL_TYPE_DOUBLE && max_length > DBL_DIG + 2)
else if (fld_type == MYSQL_TYPE_DOUBLE && max_length > DBL_DIG + 2)
{
max_length= DBL_DIG + 7;
max_length= MAX_DOUBLE_STR_LENGTH;
decimals= NOT_FIXED_DEC;
}
}
}
else
max_length= (fld_type == MYSQL_TYPE_FLOAT) ? FLT_DIG+6 : DBL_DIG+7;
break;
......
......@@ -251,6 +251,11 @@ MY_LOCALE *my_locale_by_number(uint number);
#define PRECISION_FOR_DOUBLE 53
#define PRECISION_FOR_FLOAT 24
/* -[digits].E+## */
#define MAX_FLOAT_STR_LENGTH (FLT_DIG + 6)
/* -[digits].E+### */
#define MAX_DOUBLE_STR_LENGTH (DBL_DIG + 7)
/*
Default time to wait before aborting a new client connection
that does not respond to "initial server greeting" timely
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment