I'm loading a bunch of semi-structured data (JSON) into my database through Snowflake. The timestamp values in the entries are javascript timestamps that look like this:
"time": 1621447619899
Snowflake automatically converts this into a timestamp variable that looks like this:
53351-08-15 22:04:10.000.
All good so far. However, I think that the new timestamp is wrong. The actual datetime should by May 19, 2021 around 12pm MDT. Am I reading it wrong? Is it dependent on the timezone that my Snowflake instance is in?
When comparing the following options manually in SQL:
with x as (
SELECT parse_json('{time:1621447619899}') as var
)
SELECT var:time,
var:time::number,
var:time::varchar::timestamp,
1621447619899::timestamp,
'1621447619899'::timestamp,
var:time::timestamp
FROM x;
It appears that what you want to do is execute the following:
var:time::varchar::timestamp
Reviewing the documentation it does look like the to_timestamp is looking for the number as a string, so you need to cast to varchar first, and then cast to timestamp, otherwise you get what you are getting.
The question says that Snowflake transforms it to "53351-08-15 22:04:10.000" looks right, but it doesn't look right to me.
When I try the input number in Snowflake I get this:
select '1621447619899'::timestamp;
-- 2021-05-19T18:06:59.899Z
That makes a lot more sense.
You'll need to provide more code or context for further debugging - but if you tell Snowflake to transform that number to a timestamp, you'll get the correct timestamp out.
See the rules that Snowflake uses here:
https://docs.snowflake.com/en/sql-reference/functions/to_timestamp.html#usage-notes
The ::timestamp handles strings and numeric inputs differently. I.e. a string is added to 1970-01-01 as milliseconds (correct) whereas the numeric value is added in seconds which returns a date way in the future "53351-08-18 20:38:19.000".
SELECT TO_VARCHAR(1621447619899::timestamp) AS numeric_input
,'1621447619899'::timestamp AS string_input
numeric_input = 53351-08-18 20:38:19.000
string_input = 2021-05-19 18:06:59.899
Solutions are to convert to a string or divide by 1000:
SELECT TO_TIMESTAMP(time::string)
SELECT TO_TIMESTAMP(time/1000)
Related
Probably it's super simple but i've been stuck some hours on this.
I have a column called "Publish_Date" which is a varchar, but my date shows like this: 17.01.11 (year.day.month) and I want to convert it to a date (at this point, any date format it's ok).
Every time i tried to use "convert" or "cast" it gives me a syntax error or the data doesn't change or all the data in the column changes to "null" values.
I'd appreciate if you can help me.
Assuming your data is all greater than 2000 then you can add missing part of YEAR then cast it.
SELECT CAST(CONCAT('20', Publish_Date) AS DATETIME);
You can use STR_TO_DATE with the format %y.%m.%d since this is how your date value is stored
select
str_to_date(birth_date, '%y.%m.%d')
from
mytable
Here is an SQL Fiddle I created for this case
I have a large dataset with employees' time entries. The current date format is MM/dd/yyyy. However, I need to convert all the dates into yyyy-MM-dd format.
I have tried the following:
Update human_resources.timekeeping
Set Actual_Date = str_to_date(Actual_Date,'%d-%m-%Y');
Got the errror messsage Error Code: 1411. Incorrect datetime value: '' for function str_to_date.
My SQL version is 5.7.18-log.
I tried to view SQL mode using SELECT ##sql_mode; and I got NO ENGINE SUBSTITUTION.
I have tried to retrieve the value like shown below and it was working fine.
Converting varchar mm/dd/yy to date format yyyy-mm-dd
However, updating the data would not work. I need to update the actual records, not insert new records.
Hope someone can help me regarding this. Thank you in advance!
EDIT: The data type for Actual_Date is VARCHAR.
Apologies if my explanation may be a bit confusing. But I am using this data set to display and filter time entries in a gridview. When I am filtering dates, say for example (01/15/2022-01/25/2022), data from 2021 is also being displayed. When I tried to manually change the format of some of my data in sql to yyyy-MM-dd, my code seemed to be working fine. The problem is there are a lot of data in this table, which is why manually updating the format is impossible. What is the first thing that I need to do? I'm sorry this is all still a bit confusing for me.
My apologies if you have already taken the following things into consideration but I thought them worth mentioning.
Given that you say this is a "large dataset" I assume this is a table that is currently in use. Does the existing application rely on the Actual_Date being in that string format? Does it rely on a fixed number of columns in the table? Some poorly written applications can be very brittle when it comes to changing underlying data structure.
You may want to consider creating a copy of the current table, modifying the structure of the copy, and replacing the original with a view with the same columns and formats as the original. This way you get improved data but reduce risk to existing application.
In the title and first line of your question you state that the current format is MM/dd/yyyy
Update human_resources.timekeeping Set Actual_Date = str_to_date(Actual_Date,'%m/%d/%Y');
Your separator is / not -
%d-%m-%Y >> %d/%m/%Y
I've got a table setup which has populated data. In column "date", I have dates in the following format:
yyyymmdd i.e. 20131110
I have created a new field and called it newdate with the text format.
Then, I open up the SQL window and put the following in
UPDATE wl_daily
SET
newdate = UNIX_TIMESTAMP(date)
For some reason, it is running correctly, however it only outputs NULL to all the rows. Also, the column name is blank for some reason
Any suggestions?
That's because your field in a string and you're trying to add timestamp to it which is not a string. You need to use a valid datetime field like timestamp for this to work.
Advice: don't store dates and times as strings. Store them in their native format. It makes working with dates and times much easier.
While John Cronde's answer is correct - it doesnt help your situtation
UNIX_TIMESTAMP(STR_TO_DATE(`date`, '%Y%m%d'))
will do the conversion for example
SELECT UNIX_TIMESTAMP(STR_TO_DATE('20131111', '%Y%m%d'))
returns
unix_timestamp(STR_TO_DATE('20131111', '%Y%m%d'))
---------------------------------------------------
1384128000
You should only use this to convert your columns to the date specific columns. Converting each time you need a number will add load and slow down the query if used in production
I've got this as the select part of my query:
SELECT cast(cast(exp_channel_titles.edit_date as char(14)) as datetime) AS Edit_Date
That takes data from a db in this format 20130501092128 and returns it in this format 2013-05-01 09:21:28
I can only assume it is some kind of magic as i don't fully understand how this works tbh.
But, i need to change the format of the date that it spits out to this format: %d/%m/%Y %k:%i:%s
I can honestly say i have no idea how to do this in that query, i've tried adding it as a param to datetime (is that even a mysql function?!?) but no joy and many other poor attempts that i wont go into.
If anyone can help, i'd be hugely grateful!
MySql automatically converts 20130501092128 to a date and time field, even if it is a VARCHAR or a INT, and you can just use this:
SELECT DATE_FORMAT(exp_channel_titles.edit_date, '%d/%m/%Y %k:%i:%s')
Please see fiddle here.
You can change output format using DATE_FORMAT() function from MySQL. Here is the documentation post about it.
https://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_date-format
You can change the output format into whatever format you want, but if you recieve that data into an application, modifies it and return that data to server (editing a row for example). Remember to reformat it into a valid date for MySQL.
If you dont know how to do it, just have to do this into your query:
SELECT DATE_FORMAT(cast(cast(exp_channel_titles.edit_date as char(14))
as datetime), '%e/%m/%Y %k:%i:%s') AS Edit_Date
I have a csv file that has a date field in a format like (among other fields):
17DEC2009
When I do a mysqlimport, the other fields are imported properly, but this field remains 0000-00-00 00:00:00
How can I import this date properly? Do I have to run a sed/awk command on the file first to put it into a proper format? If so, what would that be like? Does the fact that the month is spelled out instead of a number matter?
STR_TO_DATE() enables you to convert a string to a proper DATE within the query. It expects the date string, and a format string.
Check the examples in the manual entry to figure out the correct format.
I think it should be along the lines of %d%b%Y (However the %b is supposed to produce Strings like Dec instead of DEC so you will have to try out whether it works).
I had this issue in the past. What I had to do was to utilize LOAD DATA and set the appropriate expression here -
[SET col_name = expr,...]
http://dev.mysql.com/doc/refman/5.1/en/load-data.html
Here is the approach I took to solve similar problem. My use case was bit complex with so many columns, but making here simple to present the solution.
I have Persons table with (Id int autogen, name varchar(100),DOB date), and few million of data(name,DOB) needs to be populated from CSV file.
Created additional column in persons table with name like (varchar_DOB varchar(25)).
Imported data using mysqlimport utility into columns(name,varchar_DOB).
Executed update query that updated DOB column using str_to_date(varchar_DOB,'format') function.
Now, I have expected data populated DOB column.
The same logic could be applied in doing even other kind of data formatting like double,time_stamp etc.