Any one have any idea how 'TO_TIMESTAMP_TZ' function works internally in oracle.
I want to know how it converts timestamp to timezone
The documentation is very handy for questions like this.
TO_TIMESTAMP_TZ converts a string into a timestamp with timezone information. It doesn't convert something that's already a timestamp into a timestamp with timezone information, without first having a conversion back into a string - which, as I'm sure you're aware, you should always do explicitly.
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I have to get the max payment date on an invoice and I am having trouble with the date format. I do not need the max in this formula as I am using the format in a reporting tool that is pulling the max from what it finds for me.
Using "to_char({datefield},'mm/dd/yyyy')" works for displaying that date the way we would like BUT when you use summary function MAX it does not pull the correct date because it is looking at a string and not a date (it will think 12/3/21 is larger than 3/2/22).
Another thing I have tried is trunc - "trunc({datefield})" which gives us the correct max date but it changes the formatting. For example if the date prior to the formula being applied is "8/12/21 12:00:00:000" the trunc formula will display it as 12-08-21 which is horribly wrong.
Long story short is I need a way to change a date/time to date with the format of 'mmmm/dd/yyyy' WITHOUT converting it to a string with something like to_char. Thank you!!!!
A DATE is a binary data type consisting of 7 bytes representing: century, year-of-century, month, day, hour, minute and second. It ALWAYS has all of those components and it is NEVER stored with any (human-readable) format.
What you are seeing when a date is displayed is the client application you are using to access the database making a decision to be helpful to you, the user, and display the binary DATE provided by the database in a human-readable format.
If you want to change how the DATE is displayed then you either need to:
Change the settings on the client application that controls how it formats dates when it displays them to you; or
Change the data-type so that it is no longer a DATE (which does not have a format) to a data type where the values of the date can be formatted (such as a string). You can do this using TO_CHAR.
If you want to find the maximum then do it BEFORE applying the formatting:
SELECT TO_CHAR(MAX({datefield}),'mm/dd/yyyy')
FROM your_table;
I have a conversation today with my engineering coworkers about application and database design in Fintech.
How do we handle time? We all know that we need to store the datetime information normalized in UTC. But our debate is among whether we should store in 1) unix epoch timestamp which is an integer in our database, for example, 1596507157. which is 08/04/2020 # 2:12am UTC or 2) store in ISO 8601 format in string 2020-08-04T02:12:37+00:00 or 2020-08-04T02:12:37.123456789Z
The downside of unix timestamp is obviously not immediate human-readable.
I am here looking for some design advices on whether we should adopt either approach.
In my opinion, you should store it as integer rather than string, one of many reasons is obvious, int just needs 4 byte while string as ISO 8601 takes a lot more.
What you see as downside, it doesn't impact the backend, it's just a make up (only needed on user view).
Most of database have datetime data type. I guess your 'epoch timestamp' means this datetime or timestamp data type. It's easier (and better performance) to handle datetime type for database engineer. and database also have datetime formatting function.
(Oracle/MS SQL Server - convert, MySQL - date_format, PostgreSQL - to_char ...)
In my opinion, store and handle with datetime type and use formatting function for human.
I'm using Mongoid to store DateTime. But now i'm confusing with the real date.
In mongodb , the date is stored as:
{"2013-01-14T12:50:00.000Z"}
But when i print that value, it says:
2013-01-14T19:50:00+07:00
I don't really understand whether those Date formats are the same, and which one is "right" in my current timezone ?
Thank you for your help.
Date is stored in GMT, when "printed", it is displayed in your local timezone (GMT+7?)
The default Ruby date object should be able to handle offsets in time:
http://ruby-doc.org/stdlib-1.9.3/libdoc/date/rdoc/Date.html
Whereby some way down the page it even talks about how to start manipulating it I believe:
An optional argument the offset indicates the difference between the local time and UTC.
I do believe that mongoid is already converting the time for you as can be seen by the T value within the iso date being 7 hours ahead:
2013-01-14T19:50:00+07:00
Merely if you were to print the date and/or time instead of the full output with the offset included I have no doubt you will get the real date.
I believe mongoid most likely prints the offset even when it is applied because that offset IS there (since the time is off-setted by 7 hours from UTC) it is just not applied further.
I currently store all dateTimes in the DB as UTC dates. Each users time zone offset is also stored in the DB. When I retrieve a Date it is converted back to their local date using this offset.
The problem occurs when I retrieve a date using an ajax call. The date (which is already converted using the offset) is, I think, returned as a Java Date object. The browser then decides to mess with my Date adding the clients computers time zone offset to the Date object. This is causing dates to be a day ahead of what they should be if the time component is more than 11.59am.
The only solution I can come up with is to pass them as strings in which case this of course wouldn't happen. This is a laaaast resort for me though and I would love to find a better solution or workaround for this problem.
Your browser is not messing with the dates given that browsers don't have a native date transfer variable. You have something else that is doing that. How are you sending your dates in ajax? Json? Json will only send numbers or strings. XML will only send strings.
Something is converting your sent date into a javascript date object, find out what it is.
Does hibernate have any mapping for this oracle data type:(10G)
TIMESTAMP(6) WITH TIME ZONE
I am getting:
No Dialect mapping for JDBC type: -101
My manager does not want to do the: registerHibernateType(-101, Hibernate.getText().getname())
He thinks it is too much.:)
What alternative can I have?
The answer you provide to yourself is more like a workaround than a proper solution. For the sake of the visitors looking for an answer, I'll provide my view on this:
1) Database date-based fields should be always set to UTC, never with a specific timezone. Date calculation with timezone information is an unneeded complexity. Remember that timezones usually changes twice a year for a lot of countries in the world ("daylight saving time"). There's a reason why only a few RDMBS' supports this, and there's a reason why Hibernate developers refuse to support this data-type. The patch for Hibernate is simple enough (one line of code), the implications aren't.
2) Converting your "timestamp with timezone" to a String will only cause problems later. Once you retrieve it as String, you'll need to convert it again to a Date/Calendar object, an unneeded overhead. Not to mention the risks associated with this operation.
3) If you need to know in which timezone is some user, just store the String representing the timezone offset (like "Europe/Prague"). You can use this in Java to build a Calendar with date/time and timezone, as it'll take care of DST for you.
For now, I solved the problem by:
`select TO_CHAR(TRUNC(field)) from table` //field is the one having type= timestamp with timezone
This ensures that when the query returns, the field has datatype 'String'