I am new to postgresql bot not to sql in general. I have a table that I need to read values from, on of the columns is a unix timestamp that I want to convert in to a more human readable format thus I found this:
SELECT lt,dw,up,to_char(uxts, 'YYYY-MM-DD HH24:MI:SS')
from products;
But that produces an error:
ERROR: multiple decimal points
I am lost here. I am sure someone can show me how to do it. The documentation isn't that clear to me. Postgresql 9.5 is the database.
to_char() converts a number, date or timestamp to a string, not the other way round.
You want to_timestamp()
Convert Unix epoch (seconds since 1970-01-01 00:00:00+00) to timestamp
So just apply that function on your column
SELECT lt,dw,up,to_timestamp(uxts) as uxts
from products;
This assumes that uxts is some kind of number data type (integer, bigint or double precision)
Related
Trying to query an oracle db table having date in format: 2022-06-22T12:25:06.087 (LocalDateTime.now().toString()). Column type for created_time is varchar2.
Trying to query for data between two dates. I have tried the following but it results in error "date format not recognized":
select * from MY_TABLE
where to_date(created_time, 'yyyy-MM-ddTHH:mm:ss.SSS')
between to_date('2022-07-03T10:15:06.091', 'yyyy-MM-ddTHH:mm:ss.SSS')
and to_date('2022-07-03T10:15:06.091', 'yyyy-MM-ddTHH:mm:ss.SSS');
Can anyone help me correct this query?
Format you used looks like data (in CREATED_TIME column) is stored as a timestamp. If that's so, you shouldn't convert it to another datatype (you chose TO_DATE function) but leave it as is. If you stored data as a string (that's usually a huge mistake), then apply the same to_timestamp function with the same format model as the one in between clause.
Apart from that, format model for minutes is mi (not mm; that's month), while fractional seconds is ff3 (not sss).
SELECT *
FROM my_table
WHERE created_time
BETWEEN TO_TIMESTAMP ('2022-07-03T10:15:06.091', 'yyyy-MM-dd"T"HH24:mi:ss.ff3')
AND TO_TIMESTAMP ('2022-07-03T10:15:06.091', 'yyyy-MM-dd"T"HH24:mi:ss.ff3');
I guess column created_time is of data type DATE or TIMESTAMP. Never call TO_DATE() or TO_TIMESTAMP() to a values which is already a DATE
The DATE data type does not support fractional seconds, use TIMESTAMP instead. Format literals have to be enclosed by double quotes.
Format HH is the hour in 12-hour format. I assume you need 24-hour format, which is HH24. mm (or MM) is the Month, for Minute use MI. Format identifiers are not case-sensitive, so SSS is also wrong.
Try this one:
select *
from MY_TABLE
where created_time
between TO_TIMESTAMP('2022-07-03T10:15:06.091', 'yyyy-MM-dd"T"HH24:MI:ss.ff3')
and TO_TIMESTAMP('2022-07-03T10:15:06.091', 'yyyy-MM-dd"T"HH24:MI:ss.ff3');
I have this table which stores millions of rows of data. This data has a date that indicates when was the data entered. I store the data in NUMERIC schemas with EPOCH UNIX as the format. However, I wanted to convert them to human date (yyyy-mm-dd hh:mm:ss) and later sort them by date not queried date.
However, it took me so long to find a suitable way. Here's my attempt.
I used SELECT CAST(DATE(timestamp) AS DATE) AS CURR_DT FROM dataset.table but it gave me this error:
No matching signature for function DATE for argument types: NUMERIC. Supported signatures: DATE(TIMESTAMP, [STRING]); DATE(DATETIME); DATE(INT64, INT64, INT64) at [1:13]
I used this method BigQuery: convert epoch to TIMESTAMP but still didn't fully understand
I'm a novice in coding so I hope you guys understand the situation. Thanks!
If I am understanding your question correctly you would like to take a numeric EPOCH time that is stored as an integer and convert it to a timestamp?
If so you can use the following in BigQuery Standard SQL:
select TIMESTAMP_SECONDS(1606048220)
It gives the output of:
2020-11-22 12:30:20 UTC
Documentation
If you only want the date component, then you would convert to a date after converting to a timestamp. Presumably you have seconds, so you would use TIMESTAMP_SECONDS() -- but there are similar functions for milliseconds and microseconds.
For just the date:
select date(timestamp_seconds(col))
Note that this removes the time component.
We have created Phoenix views on top of Hbase tables and querying the data. One of the the columns holds epoch timestamp data and we need to convert it into a valid date format, couldn't find any appropriate functions, any help much appreciated.
If type of "the column holds epoch timestamp data" is INTEGER or BIGINT, you can use:
CAST("epoch_time" AS TIMESTAMP)
if its type is VARCHAR, you should first convert value to number through TO_NUMBER()
built-in function, i.e.
CAST(TO_NUMBER("epoch_time") AS TIMESTAMP)
My table in hive has a filed of date in the format of '2016/06/01'. but i find that it is not in harmory with the format of '2016-06-01'.
They can not compare for instance.
Both of them are string .
So I want to know how to make them in harmory and can compare them. Or on the other hand, how to change the '2016/06/01' to '2016-06-01' so that them can compare.
Many thanks.
To convert date string from one format to another you have to use two date function of hive
unix_timestamp(string date, string pattern) convert time string
with given pattern to unix time stamp (in seconds), return 0 if
fail.
from_unixtime(bigint unixtime[, string format]) converts the
number of seconds from unix epoch (1970-01-01 00:00:00 UTC) to a
string representing the timestamp of that moment in the current
system time zone.
Using above two function you can achieve your desired result.
The sample input and output can be seen from below image:
The final query is
select from_unixtime(unix_timestamp('2016/06/01','yyyy/MM/dd'),'yyyy-MM-dd') from table1;
where table1 is the table name present in my hive database.
I hope this help you!!!
Let's say you have a column 'birth_day' in your table which is in your format,
you should use the following query to convert birth_day into the required format.
date_Format(birth_day, 'yyyy-MM-dd')
You can use it in a query in the following way
select * from yourtable
where
date_Format(birth_day, 'yyyy-MM-dd') = '2019-04-16';
Use :
unix_timestamp(DATE_COLUMN, string pattern)
The above command would help convert the date to unix timestamp format which you may format as you want using the Simple Date Function.
Date Function
cast(to_date(from_unixtime(unix_timestamp(yourdate , 'MM-dd-yyyy'))) as date)
here is my solution (for string to real Date type):
select to_date(replace('2000/01/01', '/', '-')) as dt ;
ps:to_date() returns Date type, this feature needs Hive 2.1+; before 2.1, it returns String.
ps2: hive to_date() function or date_format() function , or even cast() function, cannot regonise the 'yyyy/MM/dd' or 'yyyymmdd' format, which I think is so sad, and make me a little crazy.
When ececute the following SQL syntax in Oracle, always not success, please help.
40284.3878935185 represents '2010-04-16 09:18:34', with microsecond.
an epoch date of 01 January 1900 (like Excel).
create table temp1 (date1 number2(5,10));
insert into temp1(date1) values('40284.3878935185');
select to_date(date1, 'yyyy-mm-dd hh24:mi:ssxff') from temp1
Error report: SQL Error: ORA-01861: literal does not match format
string
01861. 00000 - "literal does not match format string"
*Cause: Literals in the input must be the same length as literals in
the format string (with the exception of leading whitespace). If the
"FX" modifier has been toggled on, the literal must match exactly,
with no extra whitespace.
*Action: Correct the format string to match the literal.
Thanks to Mark Bannister
Now the SQL syntax is:
select to_char(to_date('1899-12-30','yyyy-mm-dd') +
date1,'yyyy-mm-dd hh24:mi:ss') from temp1
but can't fetch the date format like 'yyyy-mm-dd hh24:mi:ss.ff'. Continue look for help.
Using an epoch date of 30 December 1899, try:
select to_date('1899-12-30','yyyy-mm-dd') + date1
Simple date addition doesn't work with timestamps, at least if you need to preserve the fractional seconds. When you do to_timestamp('1899-12-30','yyyy-mm-dd')+ date1 (in a comment on Mark's answer) the TIMESTAMP is implicitly converted to a DATE before the addition, to the overall answer is a DATE, and so doesn't have any fractional seconds; then you use to_char(..., '... .FF') it complains with ORA-01821.
You need to convert the number of days held by your date1 column into an interval. Fortunately Oracle provides a function to do exactly that, NUMTODSINTERVAL:
select to_timestamp('1899-12-30','YYYY-MM-DD')
+ numtodsinterval(date1, 'DAY') from temp3;
16-APR-10 09.18.33.999998400
You can then display that in your desired format, e.g. (using a CTE to provide your date1 value):
with temp3 as ( select 40284.3878935185 as date1 from dual)
select to_char(to_timestamp('1899-12-30','YYYY-MM-DD')
+ numtodsinterval(date1, 'DAY'), 'YYYY-MM-DD HH24:MI:SSXFF') from temp3;
2010-04-16 09:18:33.999998400
Or to restrict to thousandths of a second:
with temp3 as ( select 40284.3878935185 as date1 from dual)
select to_char(to_timestamp('1899-12-30','YYYY-MM-DD')+
+ numtodsinterval(date1, 'DAY'), 'YYYY-MM-DD HH24:MI:SS.FF3') from temp3;
2010-04-16 09:18:33.999
An epoch of 1899-12-30 sounds odd though, and doesn't correspond to Excel as you stated. It seems more likely that your expected result is wrong and it should be 2010-04-18, so I'd check your assumptions. Andrew also makes some good points, and you should be storing your value in the table in a TIMESTAMP column. If you receive data like this though, you still need something along these lines to convert it for storage at some point.
Don't know the epoch date exactly, but try something like:
select to_date('19700101','YYYYMMDD')+ :secs_since_epoch/86400 from dual;
Or, cast to timestamp like:
select cast(to_date('19700101', 'YYYYMMDD') + :secs_since_epoch/86400 as timestamp with local time zone) from dual;
I hope this doesn't come across too harshly, but you've got to totally rethink your approach here.
You're not keeping data types straight at all. Each line of your example misuses a data type.
TEMP1.DATE1 is not a date or a varchar2, but a NUMBER
you insert not the number 40284.3878935185, but the STRING >> '40284.3878935185' <<
your SELECT TO_DATE(...) uses the NUMBER Temp1.Date1 value, but treats it as a VARCHAR2 using the format block
I'm about 95% certain that you think Oracle transfers this data using simple block data copies. "Since each Oracle date is stored as a number anyway, why not just insert that number into the table?" Well, because when you're defining a column as a NUMBER you're telling Oracle "this is not a date." Oracle therefore does not manage it as a date.
Each of these type conversions is calculated by Oracle based on your current session variables. If you were in France, where the '.' is a thousands separator rather than a radix, the INSERT would completely fail.
All of these conversions with strings are modified by the locale in which Oracle thinks your running. Check dictionary view V$NLS_PARAMETERS.
This gets worse with date/time values. Date/time values can go all over the map - mostly because of time zone. What time zone is your database server in? What time zone does it think you're running from? And if that doesn't spin your head quite enough, check out what happens if you change Oracle's default calendar from Gregorian to Thai Buddha.
I strongly suggest you get rid of the numbers ENTIRELY.
To create date or date time values, use strings with completely invariant and unambiguous formats. Then assign, compare and calculate date values exclusively, e.g.:
GOODFMT constant VARCHAR2 = 'YYYY-MM-DD HH24:MI:SS.FFF ZZZ'
Good_Time DATE = TO_DATE ('2012-02-17 08:07:55.000 EST', GOODFMT);