convert and filter datetime with mysql - date

Iam struggling to get all dates from now (all dates from today or the future).
Unfortunately my dates are in this format: '%d%m%Y %H:i' (08.06.2013 12:00)
I tried a couple of things, the last was:
SELECT * FROM `events` WHERE DATE_FORMAT(SUBSTRING(enddate,1,9),'%Y%m%d') >= DATE_FORMAT(CURDATE(),'%Y%m%d')
I thought this would convert into: (when date = 27.08.2013)
SELECT * FROM `events` WHERE 20130827 >= 20130608
But its now working... I get too much results :-/
Any help would be appreciated...
Thanks!

You should try using STR_TO_DATE (reference).
SELECT * FROM `events` WHERE STR_TO_DATE(enddate, '%Y.%m.%d') >= CURDATE();
STR_TO_DATE parses the string according to given format ('%Y.%m.%d' in your case) and returns a date string that can be used with MySQL. Once converted, you can freely compare it against other date values or functions like CURDATE. You should read the documentation for more details.
In the longer run, you will be better off using actual DATE and DATETIME columns.

Related

BigQuery Date Conversion From String

I've looked everywhere and can't find this answer. It's a pretty simple query, but I can't for the life of me figure out how to change the date.
I have a date coming in as a string, but it's not being picked up. The date is being brought in as 20170601 but I need it to be in a date format to be picked up in Tableau. I'm using Standard SQL and have tried to PARSE_DATE("%x", date) as parsed, cast(date as date), etc. and I keep getting Error: Failed to parse input string "20170918" or some variation of that error.
#standardSQL
SELECT
visitorid,
parse_DATE("%x", date) AS parse
FROM google.com:analytics-bigquery.LondonCycleHelmet.ga_sessions_20130910
The table is within `
Please advise!!
You could try doing a regex replacement to build the date string which you require:
SELECT
REGEXP_REPLACE('20170601', r"^([0-9]{4})([0-9]{2})([0-9]{2})", "\\1/\\2/\\3")
This would output 2017/06/01, which perhaps is the format you require. Actually, I don't know what format Tableau is expecting, but YYYYMMDD is usually the correct order for a date, because it will sort correctly as text. You may use any replacement you want, using the above query as an example.

Converting string timestamp into date

I have dates in a postgres database. The problem is they are stored in a string field and have values similar to: "1187222400000" (which would correspond to 07.08.2007).
I would like to convert them into readable dates usind some SQL to_date() expression or something similar but can't come up with the correct syntax to make it work.
There really isn't enough information here for a conclusion, so I propose this 'scientific-wild-ass-guess' to resolve your puzzle. :)
It appears this number is UNIX 'epoch time' in milliseconds. I'll show this example as if your string field had the arbitrary name, 'epoch_milli'. In postgresql you can convert it to a time stamp using this statement:
SELECT TIMESTAMP WITH TIME ZONE 'epoch' + epoch_milli * INTERVAL '1 millisecond';
or using this built-in postgresql function:
SELECT to_timestamp(epoch_milli / 1000)
either of which, for the example '1187222400000', produces the result
"2007-08-15 17:00:00-07"
You can do some of your own sleuthing with quite a few values selected similarly to this:
SELECT to_timestamp(epoch_milli/1000)::DATE
FROM (VALUES (1187222400000),(1194122400000)) AS val(epoch_milli);
"Well, bollocks, man. I just want the date." Point taken.
Simply cast the timestamp to a date to discard the excess bits:
SELECT to_timestamp(epoch_milli / 1000)::DATE
Of course its possible that this value is a conversion or is relative to some other value, hence the request for a second example data point.

Using Current Date Time in SAS

I am selecting the data from a table using a date string. I would like to select all rows that have a update time stamp greater than or equal to today.
The simplest way that I can think of is to put today's date in the string, and it works fine.
WHERE UPDATE_DTM >'29NOV2016:12:00'DT;
However, if I want to put something like today's date or system date, what should I put?
I used today(), but it returned all rows in the table. I am not sure if it's because today() in SAS refers to the date 1/1/1960? I also tried &sysdate, but it returned an error message seems like it requires a date conversion.
WHERE UPDATE_DTM > TODAY();
Any ideas? Your thoughts are greatly appreciated!
DATETIME() is the datetime equivalent of TODAY() (but includes the current time). You could also use dhms(TODAY(),0,0,0) if you want effectively midnight (or, for your example above, dhms(TODAY(),12,0,0) to get noon today).

Is ISO8601 the best date-format for PostgreSQL jsonb when i want to filter by the date?

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.

Tableau is reading my dates wrong

Tableau is reading my dates wrong. I have 2 columns, Date and number for each day.
The date format is “yyyymmdd” i.e. (20160617) and per day number is integer. I am fetching this data directly from SQL server and my problem is, tableau is reading my dates wrong.
So I tried DATEPARSE() to convert my date.
My DATEPARSE function is : DATEPARSE(“yyyymmdd”,”Date”) , now after using DATEPARSE function, I get NULL for my dates.
Can anyone please help me why I get NULL for dates, my query returns 30-day data which is divided into per day count.
Sample after running the query on SQL
Date Per day number
20160617 215674
Tableau does not accept this date format and I applied DateParse(), which I guess is returning string since my date is null. I would ideally like to get the correct date so I can apply a trend line on my data.
Thanks in advance.
Cheers!
You aren't using DateParse() correctly. The second parameter, which you have as "Date", should be the name of the field you want parsed. So for example, if you store 20160617 in a field called my_date_as_integer, your function should be DateParse("yyyymmdd", [my_date_as_integer])