How Insert DateTime Vales into Mysql Databse …Only End User gives Date - mysql

I am new developer in .net,I Have requirement..like this ,when user pick date from date picker not time only date he/she pick up,then click insert that time ,i want insert that date and time is into Column exist with name "EnterdDate" data type is "DATETIME". by default 00:00:00 is stored in the Time format I don't want to be stroed that values I want store The at the Time insertion MySql Server Time.
ex:user 12/03/2013 ->insert->click presently assume server time is 13:00:00
i want insert This Date value --> 2013-03-12 13:00:00 ok for me.
after 10 min I want insert the another record at time i want 2013-03-12 13:10:00
like server time in place of default time i am needed
*i don't need the DateAndTime like is :2013-03-12 00:00:00 not Ok for me.
please give best answer the above question.**

Use ADDTIME() to add the CURTIME() to the given date literal:
INSERT INTO my_table
(EnteredDate)
VALUES
(ADDTIME(CAST('2013-03-12' AS DATETIME), CURTIME())
One needs to CAST() the literal to a DATETIME value because ADDTIME() does not work with DATE types.

Related

Subtract 5 hours from a datetime value that is type timestamp with timezone

I am querying a table that has a datetime column and the value is in the format time stamp with time zone. I've tried doing a select hour(timestamp,-5) as NTime and different variants of that, but the furthest I get is an error stating the timestamp is not a valid name/type. I'm officially going off the deep end on this....
Basically, I just need the new alias column values to be a time stamp that is 5 hours behind the timestamp that is in the original table. Thank you all in advance!!
MariaDB / MySQL doesn't have a "timestamp with timezone" data type.
DATETIMEs are simple wall time, and TIMESTAMPs are UNIX time_t timestamps (the number of seconds since 1970-01-01T00:00:00UTC).
You can convert DATETIME values from one time zone to another by with tz_convert().
SELECT tz_convert('2022-04-08 21:53', 'America/Chicago', 'UTC')
for example.
Or, just to do date arithmetic you can do stuff like this.
SELECT '2022-04-08 21:53' - INTERVAL 5 HOUR

Why I can't store a timestamp in mysql / phpmyadmin?

I have a table created in phpMyAdmin and it contains two fields: start_time and text_modified. It looks like this
so the start_time might be null.
When I'm filling the data in phpmyadmin I can choose the date and time that should be represented as this timestamp:
After doing so I expect to store a timestamp value in this field instead of date time. But when I do a query SELECT start_time from table I see there this:
So I assumed that it is just the php my admin that shows me automatically all dates as a date time value instead of timestamps. But now when I do a query: SELECT FROM_UNIXTIME(start_time) FROM table I'm getting those results:
and instead I want normal dates here. What is going wrong here?
In a timestamp you can insert datetime values, that are internally stored as integers (the seconds since 1970-01-01 as you probably know). When you select them, they are displayed as date and time.
So far so good.
When you have values like 0000-00-00 00:00:00 you probably inserted NULL values or invalid dates or dates out of range for the integer value. Using FROM_UNIXTIME() doesn't make sense here, since this function calculates a date and time value from an integer value. This integer value of the timestamp column is like I said only used internally. Therefore you get NULL values for valid dates and 1970-01-01 for invalid dates since those were presumably treated as 0 and 0 seconds since 1970-01-01 00:00:00 is, surprise, 1970-01-01 00:00:00.

Query Time range between Dates using DATETIME mysql

I have a database table that has fields as such :
TIME(Datetime) Update_ID
2013-11-25 05:00:14 XC3
2013-11-25 06:00:13 XC4
2013-11-25 06:00:19 XC5
2013-12-25 23:00:14 XC6
2013-12-25 24:00:00 XC7
So assuming i want to find a trend on the updates to know which period of the day has the a particular number of updates, what i initially think of is doing something like this :
SELECT COUNT(TIME) FROM table WHERE TIME between '06:00:00' and '12:00:00'
But this doesn't work because i think since the date is not added with the time, a default value for date is added(some date around 1970). If, i add the beginning and enddate in my query, i am afraid it won't give me the results i need.
Use
WHERE HOUR(TIME)...GROUP BY DAY(TIME)
in case you have more than 1 day
You are correct, the problem is that when you do not specify the date, a default one is added.
You can use the EXTRACT function to extract the time from a date, like this:
SELECT COUNT(*)
FROM mytable
WHERE EXTRACT(HOUR_SECOND from TIME) between 60000 and 120000
Note that the time portion in the condition is specified in a different format - i.e. as numbers, without colons and quotes.
Demo on SqlFiddle.

Convert Date to UTC timestamp in mysql

I have a table with the following columns:
|start_date |TZ |
|Dec 2, 2012 |Eastern |
|Dec 2, 2012 |GMT |
Note 1: our server is in UTC time.
Note 2:The column start_date is a date field, not a timestamp field. Dec 2nd 2012 implicitly means "2012-12-02 00:00:00"
Note 3: The above table is actually multiple normalized tables, but for simplicity, I de-normalized it.
Note 4: I can put anything into the TZ table to make this easy.
I would like to select from my_table where start_date <= now()
However, this doesn't work because of timezone. If the current date/time is
Dec 1st Eastern at 9PM (which is Dec 2nd 1AM UTC), the above query will return both results,
but I really only want the 2nd one. This is further complicated by daylight savings.
Ideally, I would like a query that does the following:
select * from my_table where convert_to_utc_timestamp(start_date,tz) <= now()
The above method would convert start_date to a timestamp and then convert it to the right timezone.
How would I do this in SQL?
There are two functions you'll probably find useful.
The first is:
STR_TO_DATE(start_date,'%M %d,%Y')
That will get your string, in the specified format, converted to a MySQL DATE datatype.
If you have the mysql.time_zone_name et al. tables populated, you can use the function:
CONVERT_TZ()
(need to check that CONVERT_TZ takes a DATE and will return a DATETIME or TIMESTAMP, or include a time component in the string being converted to get a DATETIME, e.g.
STR_TO_DATE( CONCAT(start_date,' 00:00:00'),'%M %d,%Y %T')
Wrap that expression in the CONVERT_TZ() function, e.g.
CONVERT_TZ( datetime_expr ,'US/Eastern','GMT')
To make use of the values stored in your TZ column, those are going to need to match, or you need to come up with a way to match to, the values stored in the mysql.time_zone_name table.

How to insert just year and month into date field?

I have a column called table_date which currently I am using now() to insert the current date (2011-02-23). I know I can manipulate this with sql/php to show me year and monthname. However, I want to know if it's possible to just insert into table_date the current date as year-month like this 2011-02? Thanks
A DATE field is always going to be a full date, and as far as I know, it is also always required to specify a full date.
It might be easiest to use 01, like 2011-02-01 for February 2011.
Obviously, you can format the output of a DATE field to your liking when querying it:
SELECT DATE_FORMAT(fieldname,"%Y-%m");
If you insert something like 2010-10 into a DATE column, mysql throws a warning and inserts 0000-00-00. If you do not want to specify a certain day, you can insert something like 2010-10-00. Pay attention when querying for "all entries in October 2010" since WHERE date >= '2010-10-01' will not return 2010-10-00.