Please pardon my ignorance if I have missed any documentation/solution for the same. But I searched the web and could not find an answer.
I have a simple question. In the DB2 table,I have a column of type date and the with data of format 04/25/2013 12:00:00AM . When I query the DB2 database, I want to obtain just the date and not the timestamp i.e to obtain "04/25/2013" and not "04/25/2013 12:00:00AM". I tried DATE(column name) and just gave back the complete value including the time stamp.
This looks like a TIMESTAMP and not a DATE column. If it is indeed a TIMESTAMP column try this:
select varchar_format(current timestamp, 'MM/DD/YYYY') from sysibm.sysdummy1 ;
Just replace the current timestamp in the above example with your column and sysibm.sysdummy1 with your table.
The good thing about varchar_format is that it lets you easily format the timestamp. Just change the 'MM/DD/YYYY' part to 'YYYY.MM.DD' to get a format like '2017.08.18'.
Related
I am beginner in Backend technology and I am developing one query in Typeorm QueryBuilder + PostgreSQL.
My query is look like this :
But I can't convert my timestamp into following format. Can anyone who has expertise in it, please help me to select all records with timestamp in specific format.
I am suffering this things from last two days but still not find any solution. Actually I want to compare this date format in having clause. so I want to first select that date format then I can use that same method to compare column with current date and previous dates.
I'm new to PostgreSQL and I have the following question:
I have a table with just an id-column and a data-column, which uses the jsonb-type. Inside the jsonb-object I have a datetime field. I read in various posts, that I should use the ISO-8601 dateformat to store in the DB.
I want to filter my table by date like this:
SELECT * FROM table WHERE data->'date' > '2016-01-01T00:00'
Is this really the best date-format for this purpose?
Thanks in advance :)
IMHO Your query should produce
ERROR: operator does not exist: jsonb > timestamp with time zone
If I get it right. In case you change -> to ->> it should get a text value instead of jsonb field (which is also not comparable to timestamp).
It should be smth like
SELECT * FROM table WHERE (data->>'date')::timestamptz > '2016-01-01T00:00' to work
The big advantage of that format is that string order corresponds to date order, so a comparison like the one you quote in your question would actually work as intended.
A second advantage is that a timestamp in that format can easily be converted to a PostgreSQL timestamp with time zone value, because the type input function understands this format.
I hope you are not dealing with dates “before Christ”, because it wouldn't work so easily with those.
I'm trying to add only the current date in "DD/MM/YYYY" format in a field of type ' timestamp in PostgreSQL' .
I try:
select to_char(now(),'DD/MM/YYYY') as date;
But PostgreSQL return me:
TIP : You will need to rewrite the expression or apply a type conversion.
There is no such thing as "only the date" in a timestamp field. A timestamp field will store timestamps.
Try using the date type instead. Please read about this here.
Also, please consider using the ISO 8601 format instead. Getting used to it helps in a lot of cases.
Human-readable formats like "DD/MM/YYYY" should only be used for presentation.
If you want to use timestamp fields and insert a human-readable formatted dates, then you are looking for:
to_timestamp('05/04/2016', 'DD/MM/YYYY')
If it is about the current date, then Postgres provides the CURRENT_DATE function, which you may use:
SELECT CURRENT_DATE;
INSERT INTO t (timestamp_field) VALUES (CURRENT_DATE);
I have a small SQLite3 DB that has an integer field called "dt". It stores date and time.
I am having trouble extracting just the date from the field. However, doing a "select date(dt) from log2" returns nothing. I've tried strftime() as well, but no cigar.
Please help. This is driving me insane.
Thanks.
if the Date in dt is wellformed then the result shoeld be the date from a datetime column
select date('2011-01-01 23:55:55');
should receive
2011-01-01
but
select date('2011-01-01 23:55:5');
would receive nothing
so the dt coloum have to be wellformed
I have create one field in sql server database as nvarchar datatype and store some date like 'd/MM/yyyy' and 'dd/MM/yyyy' format previously. Now i want to get all data in 'dd/MM/yyyy' format using query it is possible?
You can cast the field to datetime in the query:
select cast(YourField as datetime)
from YourTable
where isdate(YourField) = 1
The where isdate(YourField) = 1 part is necessary to filter out rows where the value is no valid date (it's a nvarchar field, so there could be things like abc in some rows!)
But you should really change the field to datetime in the long term, as already suggested by Christopher in his comment.
Casting like described above is always error-prone because of the many different data formats in different countries.
For example, I live in Germany where the official date format is dd.mm.yyyy.
So today (December 9th) is 9.12.2011, and running select cast('9.12.2011' as datetime) on my machine returns the correct datetime value.
Another common format is mm/dd/yyyy, so December 9th would be 12/9/2011.
Now imagine I have a nvarchar field with a date in this format on my German machine:
select cast('12/9/2011' as datetime) will return September 12th (instead of December 9th)!
Issues like this can easily be avoided by using the proper type for the column, in this case datetime.