I have a table with a text column in the following format:
5/30/2021 9:35:18 AM
I'm trying to convert this to date(yyyy-MM-dd) but I get null values when I use cast, to_date.
Is there any way to get the above data in the yyyy-mm-dd format?
Use Databricks Datetime Patterns. According to SparkSQL documentation on the Databricks website, you can use datetime patterns specific to Databricks to convert to and from date columns. First, you need to convert the text column to a date column like this:
to_date('5/30/2021 9:35:18 AM','M/d/y h:m:s a')
M - month, d - day of month, y - year, h - hour of day (12-hour), m - minute of hour, s - second of minute, a - AM/PM
Once the column is converted to a date, you can easily use the same datetime patterns to convert it back to a specific format. Use the following command to convert it to the required format:
date_format(date to_date('5/30/2021 9:35:18 AM','M/d/y h:m:s a'), 'yyyy/MM/dd')
Note: Depending upon whether you're getting zero left padded days, months, hours, minutes, and seconds, you'll need to tweak the above command.
Related
I have seperate date and time columns in my table. Date as mm/dd/yyyy, time as hh:mm but i can change the format. I want to list data between 2 date/time. How can I do that?
select * from testtable where date >= '01/10/2022' AND date <= '01/10/2023' AND time >= '13:45' AND time <= '15:50'
I wrote it but of course it doesn't work like what i expected.
The best fix and really the only one you want here would be to start storing your timestamps in a sortable ISO format yyyy-mm-dd hh:ii:ss. Then, use this query:
SELECT *
FROM testtable
WHERE date BETWEEN '2022-01-10 13:45:00' AND '2023-01-10 15:50:00';
The thing to realize here is that SQLite does not actually have a date column type. Rather, you always store your dates/timestamps as text, and therefore it is crucial to use an ISO sortable format as shown above.
If your target is sqlite, it lacks complex timestamp types. But you have another option here. You can store that as unix timestamp, it is an integer representing the number of seconds offset from the epoch which is 1970-01-01 00:00:00 UTC. The table format would then be:
CREATE TABLE testtable (
date INTEGER
);
You can the use the unixepoch function to translate a string representation to that unix timestamp format. To insert a new date, you would use:
INSERT INTO testtable (date) VALUES (unixepoch('2023-01-11T11:30:00+01:00'))
Finding a matching row is now as easy to compare integers together. You can convert the datetime representation to unix timestamp at the application level, most programming environments provide such time utility functions/library. Or can still use the unixepoch function from sqlite for your where clause.
SELECT * FROM testtable
WHERE date >= unixepoch('2022-10-01T13:45:00Z')
AND date <= unixepoch('2023-10-01T15:50:00Z')
The final Z indicates an UTC time zone but you can adjust that with another +HH:00 extenstion instead which reflect the offset from utc of your datetime representation.
so I'm trying to learn how to deal with this.
the key partition column is "date" as a string (YYYYMMDD).
so its a character string, not a numeric date format.
I'm having trouble understanding how I can WHERE filter off this by normal date ranges like
where date > CURRENT_DATE -30
or
WHERE date BETWEEN '20210512' AND '20210517'
How does this work? Should the date column be converted first?
This is SQL in a HIVE database.
The best way is to convert the comparison date to a string. Many databases support to_char():
where date > to_char(current_date - 30, 'YYYYMMDD')
Those that do not would have some other function to convert the date to a string.
Note that this formulation allows the use of indexes and table partitions to optimize the query.
I'm attempting to convert the time into a YYYY:MM:DD format. I have already truncated it from a timestamp format. However, with the trunc, I come up with this format (using Periscope):
Here is the date part of my query
You can try this:
SELECT FORMAT(your_date, 'yyyy:MM:dd')
I am trying to extract the date and time from a field in Teradata.
The field in question is:
VwNIMEventFct.EVENT_GMT_TIMESTAMP
Here is what the data look like:
01/02/2012 12:18:59.306000
I'd like the date and time only.
I have tried using EXTRACT(Date, EXTRACT(DAY_HOUR and a few others with no success.
DATE_FORMAT() does not appear to work since I'm on Teradata.
How would I select the date and time from VwNIMEventFct.EVENT_GMT_TIMESTAMP?
If the datatype of EVENT_GMT_TIMESTAMP is a TIMESTAMP, it's simple Standard SQL:
CAST(EVENT_GMT_TIMESTAMP AS DATE)
CAST(EVENT_GMT_TIMESTAMP AS TIME)
If it's a CHAR you need to apply a FORMAT, too:
CAST(CAST(EVENT_GMT_TIMESTAMP AS TIMESTAMP FORMAT 'dd/mm/yyyyBhh:mi:SS.s(6)') AS DATE)
CAST(CAST(EVENT_GMT_TIMESTAMP AS TIMESTAMP FORMAT 'dd/mm/yyyyBhh:mi:SS.s(6)') AS TIME)
Edit:
For simply changing the display format you need to add a FORMAT and a CAST to a string:
CAST(CAST(EVENT_GMT_TIMESTAMP AS FORMAT 'YYYYMMDDHHMI') AS CHAR(12))
or
CAST(CAST(EVENT_GMT_TIMESTAMP AS FORMAT 'YYYYMMDDHHMISS') AS CHAR(14))
If you don't care about display, just want to truncate the seconds:
EVENT_GMT_TIMESTAMP - (EXTRACT(SECOND FROM EVENT_GMT_TIMESTAMP) * INTERVAL '1.000000' SECOND)
Working with timestamps is a bit tricky :-)
I know this is an old topic, but I've struggled with this too. Try:
CAST(EVENT_GMT_TIMESTAMP AS TIMESTAMP(0))
The result will be
01/02/2012 12:18:59
The datatype will still be timestamp, but it will just be the date and time with no microseconds (looks just like a datetime object in Microsoft SQL).
I am new to Oracle, and I need to save date and time in an Oracle database.
I am using time stamp as datatype for row. But now my problem is it saves date and time in 12 hours format like this 17/11/2011 10:10:10 PM.
But I need it in 24 hours format like 17/11/2011 22:10:10. I didn't understand the results that Google search result provided. Can any one please help me by posting some code.
Oracle always stores timestamps (and dates) in a packed binary format that is not human readable. Formatting is done only when a timestamp (or a date) is converted to a string.
You can control the formatting of your output by coding an explicit to_char. For example
SELECT to_char( your_timestamp_column, 'DD/MM/YYYY HH24:MI:SS' )
FROM your_table
Oracle stores timestamps in an internal format (with a default representation).
You can customize this representation on output like with the to_char() function.
For input (into the database) you can use to_date().