set time_zone='+03:00'; set timestamp=unix_timestamp('2011-01-01 01:01:01.123456'); select sec_to_time(12345), sec_to_time(12345.6789), sec_to_time(1234567e-2); sec_to_time(12345) 03:25:45 sec_to_time(12345.6789) 03:25:45.6789 sec_to_time(1234567e-2) 03:25:45.670000 select now(), curtime(0), utc_timestamp(1), utc_time(2), current_time(3), current_timestamp(4), localtime(5), localtimestamp(6), time_to_sec('12:34:56'), time_to_sec('12:34:56.789'); now() 2011-01-01 01:01:01 curtime(0) 01:01:01 utc_timestamp(1) 2010-12-31 22:01:01.1 utc_time(2) 22:01:01.12 current_time(3) 01:01:01.123 current_timestamp(4) 2011-01-01 01:01:01.1234 localtime(5) 2011-01-01 01:01:01.12345 localtimestamp(6) 2011-01-01 01:01:01.123456 time_to_sec('12:34:56') 45296.000000 time_to_sec('12:34:56.789') 45296.789000 select sec_to_time(time_to_sec('1:2:3')), sec_to_time(time_to_sec('2:3:4.567890')); sec_to_time(time_to_sec('1:2:3')) 01:02:03.000000 sec_to_time(time_to_sec('2:3:4.567890')) 02:03:04.567890 select time_to_sec(sec_to_time(11111)), time_to_sec(sec_to_time(11111.22222)); time_to_sec(sec_to_time(11111)) 11111 time_to_sec(sec_to_time(11111.22222)) 11111.22222 select current_timestamp(7); ERROR 42000: Too big precision 7 specified for 'now'. Maximum is 6. select curtime(7); ERROR 42000: Too big precision 7 specified for 'curtime'. Maximum is 6. drop table if exists t1; create table t1 select sec_to_time(12345), sec_to_time(12345.6789), sec_to_time(1234567e-2), now(), curtime(0), utc_timestamp(1), utc_time(2), current_time(3), current_timestamp(4), localtime(5), localtimestamp(6), time_to_sec(123456), time_to_sec('12:34:56.789'); show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `sec_to_time(12345)` time DEFAULT NULL, `sec_to_time(12345.6789)` time(4) DEFAULT NULL, `sec_to_time(1234567e-2)` time(6) DEFAULT NULL, `now()` datetime NOT NULL DEFAULT '0000-00-00 00:00:00', `curtime(0)` time NOT NULL DEFAULT '00:00:00', `utc_timestamp(1)` datetime(1) NOT NULL DEFAULT '0000-00-00 00:00:00.0', `utc_time(2)` time(2) NOT NULL DEFAULT '00:00:00.00', `current_time(3)` time(3) NOT NULL DEFAULT '00:00:00.000', `current_timestamp(4)` datetime(4) NOT NULL DEFAULT '0000-00-00 00:00:00.0000', `localtime(5)` datetime(5) NOT NULL DEFAULT '0000-00-00 00:00:00.00000', `localtimestamp(6)` datetime(6) NOT NULL DEFAULT '0000-00-00 00:00:00.000000', `time_to_sec(123456)` bigint(17) DEFAULT NULL, `time_to_sec('12:34:56.789')` decimal(22,6) DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 select * from t1; sec_to_time(12345) 03:25:45 sec_to_time(12345.6789) 03:25:45.6789 sec_to_time(1234567e-2) 03:25:45.670000 now() 2011-01-01 01:01:01 curtime(0) 01:01:01 utc_timestamp(1) 2010-12-31 22:01:01.1 utc_time(2) 22:01:01.12 current_time(3) 01:01:01.123 current_timestamp(4) 2011-01-01 01:01:01.1234 localtime(5) 2011-01-01 01:01:01.12345 localtimestamp(6) 2011-01-01 01:01:01.123456 time_to_sec(123456) 45296 time_to_sec('12:34:56.789') 45296.789000 drop table t1; select unix_timestamp('2011-01-01 01:01:01'), unix_timestamp('2011-01-01 01:01:01.123456'), unix_timestamp(cast('2011-01-01 01:01:01.123456' as datetime(0))), unix_timestamp(cast('2011-01-01 01:01:01.123456' as datetime(4)));; unix_timestamp('2011-01-01 01:01:01') 1293832861.000000 unix_timestamp('2011-01-01 01:01:01.123456') 1293832861.123456 unix_timestamp(cast('2011-01-01 01:01:01.123456' as datetime(0))) 1293832861 unix_timestamp(cast('2011-01-01 01:01:01.123456' as datetime(4))) 1293832861.1234 select from_unixtime(unix_timestamp('2011/1/1 1:1:1')), from_unixtime(unix_timestamp('2011/1/1 1:1:1.123456')), from_unixtime(unix_timestamp(cast('2011/1/1 1:1:1.123456' as datetime(0)))), from_unixtime(unix_timestamp(cast('2011/1/1 1:1:1.123456' as datetime(4))));; from_unixtime(unix_timestamp('2011/1/1 1:1:1')) 2011-01-01 01:01:01.000000 from_unixtime(unix_timestamp('2011/1/1 1:1:1.123456')) 2011-01-01 01:01:01.123456 from_unixtime(unix_timestamp(cast('2011/1/1 1:1:1.123456' as datetime(0)))) 2011-01-01 01:01:01 from_unixtime(unix_timestamp(cast('2011/1/1 1:1:1.123456' as datetime(4)))) 2011-01-01 01:01:01.1234 select sec_to_time(3020399.99999), sec_to_time(3020399.999999), sec_to_time(3020399.9999999); sec_to_time(3020399.99999) sec_to_time(3020399.999999) sec_to_time(3020399.9999999) 838:59:59.99999 838:59:59.999999 838:59:59.999999 select sec_to_time(-3020399.99999), sec_to_time(-3020399.999999), sec_to_time(-3020399.9999999); sec_to_time(-3020399.99999) sec_to_time(-3020399.999999) sec_to_time(-3020399.9999999) -838:59:59.99999 -838:59:59.999999 -838:59:59.999999 select 20010101000203.000000004 + interval 1 day; 20010101000203.000000004 + interval 1 day 2001-01-02 00:02:03.000000 select 20010101000203.4 + interval 1 day; 20010101000203.4 + interval 1 day 2001-01-02 00:02:03.4 set @a=cast('2011-01-02 12:13:14' as datetime); select @a + interval 1 minute; @a + interval 1 minute 2011-01-02 12:14:14 select @a + interval 10 microsecond; @a + interval 10 microsecond 2011-01-02 12:13:14.000010 select @a + interval 10 microsecond + interval 999990 microsecond; @a + interval 10 microsecond + interval 999990 microsecond 2011-01-02 12:13:15.000000 set @a='2011-01-02 12:13:14.123456'; create table t1 select CAST(@a AS DATETIME) as dauto, CAST(@a AS DATETIME(0)) as d0, CAST(@a AS DATETIME(1)) as d1, CAST(@a AS DATETIME(2)) as d2, CAST(@a AS DATETIME(3)) as d3, CAST(@a AS DATETIME(4)) as d4, CAST(@a AS DATETIME(5)) as d5, CAST(@a AS DATETIME(6)) as d6, CAST(@a AS TIME) as tauto, CAST(@a AS TIME(0)) as t0, CAST(@a AS TIME(1)) as t1, CAST(@a AS TIME(2)) as t2, CAST(@a AS TIME(3)) as t3, CAST(@a AS TIME(4)) as t4, CAST(@a AS TIME(5)) as t5, CAST(@a AS TIME(6)) as t6; show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `dauto` datetime DEFAULT NULL, `d0` datetime DEFAULT NULL, `d1` datetime(1) DEFAULT NULL, `d2` datetime(2) DEFAULT NULL, `d3` datetime(3) DEFAULT NULL, `d4` datetime(4) DEFAULT NULL, `d5` datetime(5) DEFAULT NULL, `d6` datetime(6) DEFAULT NULL, `tauto` time DEFAULT NULL, `t0` time DEFAULT NULL, `t1` time(1) DEFAULT NULL, `t2` time(2) DEFAULT NULL, `t3` time(3) DEFAULT NULL, `t4` time(4) DEFAULT NULL, `t5` time(5) DEFAULT NULL, `t6` time(6) DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 select * from t1; dauto 2011-01-02 12:13:14 d0 2011-01-02 12:13:14 d1 2011-01-02 12:13:14.1 d2 2011-01-02 12:13:14.12 d3 2011-01-02 12:13:14.123 d4 2011-01-02 12:13:14.1234 d5 2011-01-02 12:13:14.12345 d6 2011-01-02 12:13:14.123456 tauto 12:13:14 t0 12:13:14 t1 12:13:14.1 t2 12:13:14.12 t3 12:13:14.123 t4 12:13:14.1234 t5 12:13:14.12345 t6 12:13:14.123456 drop table t1; explain extended select cast(cast(@a as datetime(4)) as time(0)); id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used Warnings: Note 1003 select cast(cast((@`a`) as datetime(4)) as time) AS `cast(cast(@a as datetime(4)) as time(0))` select cast(cast(@a as time(2)) as time(6)); cast(cast(@a as time(2)) as time(6)) 12:13:14.120000 select CAST(@a AS DATETIME(7)); ERROR 42000: Too big precision 7 specified for '(@`a`)'. Maximum is 6. SELECT CONVERT_TZ('2011-01-02 12:00:00', '+00:00', '+03:00'); CONVERT_TZ('2011-01-02 12:00:00', '+00:00', '+03:00') 2011-01-02 15:00:00 SELECT CONVERT_TZ('2011-01-02 12:00:00.123', '+00:00', '+03:00'); CONVERT_TZ('2011-01-02 12:00:00.123', '+00:00', '+03:00') 2011-01-02 15:00:00.123000 SELECT CONVERT_TZ('2011-01-02 12:00:00.123456', '+00:00', '+03:00'); CONVERT_TZ('2011-01-02 12:00:00.123456', '+00:00', '+03:00') 2011-01-02 15:00:00.123456 SELECT CONVERT_TZ(CAST('2010-10-10 10:10:10.123456' AS DATETIME(4)), '+00:00', '+03:00'); CONVERT_TZ(CAST('2010-10-10 10:10:10.123456' AS DATETIME(4)), '+00:00', '+03:00') 2010-10-10 13:10:10.1234 create table t1 (a varchar(200)); insert t1 values (now(6)); select * from t1; a 2011-01-01 01:01:01.123456 drop table t1; create table t1 (f1 timestamp(6)); insert into t1 values ('2002-07-15 21:00:00'); select time(f1) from t1; time(f1) 21:00:00.000000 select time(f1) from t1 union all select time(f1 + interval 1 second) from t1; time(f1) 21:00:00.000000 21:00:01.000000 alter table t1 modify f1 timestamp; select time(f1) from t1; time(f1) 21:00:00 select time(f1) from t1 union all select time(f1 + interval 1 second) from t1; time(f1) 21:00:00 21:00:01 alter table t1 modify f1 varchar(100); select time(f1) from t1; time(f1) 21:00:00 select time(f1) from t1 union all select time(f1 + interval 1 second) from t1; time(f1) 21:00:00.000000 21:00:01.000000 drop table t1;