I want to find the latest value of a column for particular time duration(1 minute in my case) from Kusto table.
I have timeseries data in PostgreSQL table and I am using last() function (https://docs.timescale.com/api/latest/hyperfunctions/last/)to find the latest value of scaled_value for 1 minute time bucket of PostgreSQL and I want to use same function in Kusto Table to get the latest value of scaled_value . What will be correct function to use in Kusto corresponding to last() function in Postgresql
Code I am using in PostgreSQL :
SELECT CAST(EXTRACT(EPOCH FROM time_bucket('1 minutes', timestamp) AT TIME ZONE 'UTC') * 1000 AS BIGINT) as timestamp_epoch,
vessel_telemetry.timeSeries,
last(vessel_telemetry.scaled_value, vessel_telemetry.timestamp) as scaled_value,
FROM shipping.vessel_telemetry
WHERE vessel_telemetry.ingested_timestamp >= '2022-07-20T10:10:58.71Z' AND vessel_telemetry.ingested_timestamp < '2022-07-20T10:15:33.703985Z'
GROUP BY time_bucket('1 minutes', vessel_telemetry.timestamp), vessel_telemetry.vessel_timeSeries
Corresponding code I am using in ADX
VesselTelemetry_DS
| where ingested_timestamp >= datetime(2022-07-20T10:10:58.71Z) and ingested_timestamp < datetime(2022-07-20T10:15:33.703985Z)
| summarize max_scaled_value = max(scaled_value) by bin(timestamp, 1m), timeSeries
| project timestamp_epoch =(datetime_diff('second', timestamp, datetime(1970-01-01)))*1000, timeSeries, max_scaled_value
The data that i am getting using PostgreSQL is not matching with the data I am getting from ADX Query. I think the functionality of last() function of Postgre is different from max() function of ADX. Is there any function in ADX that we can use to perform same as last() of PSQL
arg_max()
arg_max (ExprToMaximize, * | ExprToReturn [, ...])
Please note the order of the parameters, which is opposite to Timescale's last() -
First the expression to maximize, in your case timestamp and then the expression(s) to return, in your case scaled_value
Related
device_id
device_created_at
10e7983e-6a7b-443f-b0fe-d5e6485a502c
2022-08-10 20:55:16.695
i have a table where my date/time is of form: 2022-08-10 20:55:16.695 This is a timestampped object. I tried the following query but didn't return any rows:
select * from device where to_char(device_created_at,'YYYY-MM-DD HH24:MI:SS.FFF') = '2022-08-10 20:55:16.695'
The type of device_created_at is "timestamp without time zone"
How do i query based on timestamp in postgressql?
Try comparing timestamp values in place of strings:
SELECT *
FROM device
WHERE device_created_at = CAST('2022-08-10 20:55:16.695' AS TIMESTAMP)
Check the demo here.
I am trying to write a SQL query where the results would show the first value (ID) per user per day for the last year.
I tried using the query below and am able to get results for one day but when I try to change the time range to > 2021-06-01, it does not give me the results I expect.
select * from table
where value in
(
SELECT min(value)
FROM table
WHERE valueid = x
group by user
) and Time = '2022-05-30' and value is not null
i have a table where my date/time is of form: 2020-03-10 22:54:08
This is a timestampped object. I tried the following query but didn't return any rows:
select ts from table1
where cast(ts as timestamp) = '2020-03-10 22:54:08'
returns nothing.
How do i query based on date and time in postgressql?
A timestamp has microsecond resolution, so you have to use same techiques as when testing floating point numbers: Round it or use only < and > for comparison.
To retrieve data from a database, you need to refer to SQL SELECT syntax. In your situation, the ts column is already a timestamp, so there is no need to use cast(). Bear in mind, however, that a timestamp type contains fractions of a second (i.e., 2020-03-10 22:54:03.xxx), so you would be better off using a comparison operator (>,<,>=,or <=)
You can retrieve all columns by using the * syntax:
select *
from my_table
where ts >= '2020-03-10 22:54:08';
tymestamp type by default contains also microseconds, so, now() which, for example, is 2020-03-11 01:56:27.593985 here obviously is not equal to 2020-03-11 01:56:27. If you do not want to have microseconds precision in your data then declare your field like ts timestamp(0) NOT NULL DEFAULT now() which means "0 decimal digits for microseconds":
select
current_timestamp::timestamp as ts,
current_timestamp::timestamp(2) as ts2,
current_timestamp::timestamp(0) as ts0;
ts | ts2 | ts0
---------------------------+------------------------+---------------------
2020-03-11 02:02:52.98298 | 2020-03-11 02:02:52.98 | 2020-03-11 02:02:53
Actually this worked.
select distinct(ts) from my_table where ts >= '2020-03-10 22:54:08' and ts <= '2020-03-10 22:54:09'
But this doesn't give me the whole rows
But then i tried this and this worked:
select ts from table1
where to_char(ts,'YYYY-MM-DD HH24:MI:SS') = '2020-03-10 22:54:08'
I have a column date and column time on my PostgreSQL table. I wish to make a query, to filter rows that are not expired based on date and time. I tried this, but it does not works and returns an error Postgrex.Error) ERROR 42601 (syntax_error) syntax error at or nea:
from q in Line, where: fragment("date ? + time ? > NOW()", q.date, q.time)
I think this problem can be solved by not using time and date prefixes:
from q in Line, where: fragment("? + ? > NOW()", q.date, q.time)
or even
from q in Line, where: q.date + q.time < fragment("NOW()")
Provided, your columns have the correct data type
not sure if you need to run a standard query or if you are filtering via some GUI, but time and date types can be combined together via simple addition. https://www.postgresql.org/docs/current/functions-datetime.html
The following code:
WITH q AS (
SELECT* FROM (VALUES
('11:29:10'::time,'03-18-2019'::date),
('11:29:10'::time,'03-18-2021'::date)
) t ("time","date")
)
SELECT * FROM q WHERE q.time+q.date > NOW()
Should only print the date in the future, which is what you are trying to achieve.
Hope this helps!
I'm new in PostgreSQL I need to convert the minute's value in a column into hours and minutes format I have searched in various sources but failed to achive.Some one please help me to achieve this.
In mean while I try to use to_char() as follows :
UPDATE tablename SET col2 = TO_CHAR(((col1*60 ||`second`))::interval, ‘HH24:MI:SS’) where id = 145;
but I get the following error...
column "late_by" is of type timestamp with time zone but expression is of type text
LINE 2: UPDATE attendance SET late_by = TO_CHAR(((lateby*60 || 'seco...
^
HINT: You will need to rewrite or cast the expression.
It is unclear what type each column in your statement is.
But if it helps, you can perform maths on intervals
select interval '60 seconds' * 15;
or in your case, if "col1" is integer: interval '60 seconds' * col1;
your column late_by is of time timestamp, yet you want to update it with interval, not timestamp. If you want to save how much time somebody is late, better use interval, eg:
t=# create table w3 (t interval);
CREATE TABLE
t=# insert into w3 select (185||' seconds')::interval;
INSERT 0 1
t=# select * from w3;
t
----------
00:03:05
(1 row)
as you can see "conversion" to minutes done by postgres itself