Questions tagged [timestamp]
For questions about timestamp data types and/or recording a particular point in time.
281
questions
0
votes
0answers
11 views
Unexpected timestamp value in updated_at field of table
We're using an ORM for maintaining timestamp fields in a table. There are around 100 million entries done in the table per day. We're seeing an unusual behaviour where updated_at field in some of the ...
1
vote
1answer
23 views
Convert Varchar to Interval
I have a Postgresql column that is a varchar that is saving a string that looks like '2 years, 5 months' or '3 months' or '9 years, 0 months'. I can't convert the column to an interval because it's ...
0
votes
3answers
40 views
Statement of total precipitation for each hour, day or month
I store the data from the rain gauge in mySQL and needed help with listing the data. I save the data every 5 minutes and use the save date in the form of a timestamp.
At the end of each hour, ...
-2
votes
1answer
39 views
query to get start time and end time from same column based on boolean value order by primary key [closed]
As of now, this is my current query:
SELECT
MAX(CASE WHEN status = 1 THEN [timestamp] END) as machineOn
,MAX(CASE WHEN status = 0 THEN [timestamp] END) as machineOff
FROM machine_table
where ...
0
votes
0answers
26 views
How can I get all rows whos timestamp is closest to midnight (sampling timeseries)
I have a table that counts the amount of user interaction with a given item. Basically it has a table with 3 rows (item_name, time, num_interactions). The number of interactions never decreases, it ...
6
votes
2answers
513 views
Is there a performance or storage space advantage to lowering time/timestamp precision in PostgreSQL?
PostgreSQL allows time/timestamp to specify a precision:
time, timestamp, and interval accept an optional precision value p which specifies the number of fractional digits retained in the seconds ...
-1
votes
1answer
103 views
PostgreSQL Query - how to subtract timestamps and format durations (with builitin functions or otherweise)
I am looking for a solution to a problem with a select statement where I am trying to display the sleep duration.
Sleep Table
Here is the select statement I have so far:
select wakeuptime,hour from
...
1
vote
1answer
16 views
Why can't I use ALTER to set the default on a column?
Long story short, I have a table with a TIMESTAMP column where I want to make the default CURRENT_TIMESTAMP (default currently is 1971-01-01 00:00:00).
This is part of a WordPress plugin, and so ...
-1
votes
1answer
27 views
How to catagorize timestamp based on hours in postgreSQL [closed]
I am trying to categorize the timestamp by the HOUR using the arrival column categories like ['00.00 - 06.00', '06.00 - 10.00', '10.00 - 14.00', '14.00 - 18.00', '18.00 - 00.00']). I am very new to ...
1
vote
1answer
40 views
What is the reasoning behind PostgreSQL changing the timezone when changing a timestamp with time zone field?
I have a table with a "timestamp with time zone" column.
For one row, it had this value: 2021-06-24 00:00:00+02.
Then, I edited and saved it to be: 2021-06-24 11:00:00-05. Note that both the ...
3
votes
1answer
127 views
Force NOW to return new timestamps without committing the transaction
I'm aware that, in PostgreSQL, the return value of NOW() is the transaction begin timestamp. So if you use NOW() multiple times in the same transaction it will always return the same value.
And that's ...
0
votes
1answer
32 views
Date calculations give different results in different environments
This query:
WITH RECURSIVE
cte AS ( SELECT 0 n
UNION ALL
SELECT n + 1 FROM cte WHERE n < 20)
SELECT n, ('2020-04-13 00:00:00 Europe/Berlin'::timestamptz - make_interval(days => ...
1
vote
1answer
58 views
Add a number of days to a timestamp
I'd like to add (or rather subtract) a number of days from a timestamp.
For example from 2020-04-13 00:00:00 Europe/Berlin I want to subtract 20 days and I expect the result to be 2020-03-24 00:00:00 ...
4
votes
1answer
164 views
How does PostgreSQL store timestamp internally?
In case of MySQL,
TIMESTAMP values are stored as the number of seconds since the epoch ('1970-01-01 00:00:00' UTC)`
In case of PostgreSQL with the version less than or equal to 9.6
timestamp values ...
3
votes
1answer
474 views
Is it possible to automatically generate a Unix millisecond timestamp in MySQL 5.7
I have created a created_time field with BIGINT in a MySQL 5.7 table, now I want to auto generate a Unix millisecond timestamp when I insert a record. Is it possible to do this? I have tried the code ...
0
votes
2answers
922 views
MySQL - Truncated incorrect datetime value
I need to migrate some data from between to tables. The first has a varchar(255) field where a date is stored. I want to insert that date in a timestamp field in the second table.
The varchar field ...
2
votes
1answer
81 views
Cross join table row with generate_series
Currently I have
SELECT x, plans.name
FROM plans
CROSS JOIN generate_series(timestamp '2021-01-01 06:00'
, timestamp '2021-01-07 22:00'
, interval '1 hour') ...
1
vote
1answer
35 views
Getting the latest timestamp in Oracle
I am trying to create a report that has the latest member id in the first column and the old member id in the second column based on the timestamp in audits table below. Member ids are stored in ...
0
votes
3answers
268 views
Unix timestamp vs timestamptz index performance [closed]
I'm new to the world of DB admin and have a large table (2 billion rows) of cryptocurrency tick data for multiple currencies in a Postgres database. Most of my queries will involve selecting a moving ...
-1
votes
2answers
90 views
How to create an index based on a time-based function in postgres? [closed]
I have a function called hot_rank to rank posts, based on their score, and their newest_comment_time (basically a decaying power function):
create or replace function hot_rank(
score numeric,
...
0
votes
3answers
75 views
What is the difference between these extracting date method?
Assuming I have a table called MyTable, with a TimeStamp field "Created". I want only extract the Date part of this column, and in my research I found these alternatives:
SELECT created AS &...
-1
votes
2answers
239 views
Purpose to use timestamp datatype in sql server? [closed]
What is the purpose to use timestamp datatype in sql server?
Do you have a concrete example of using timestamp in real business case?
When is it relevant to use timestampe datatype?
Thank you!
0
votes
1answer
41 views
sql backup restore converts createdAt to local TZ
I have a remote MySQL DB in the cloud on JAWSDB.
I have createdAt and updatedAt timestamps for records that are in UTC TZ.
I'll backup these DBs using mysqldump -h HOST -u USER -p > backup.sql. I ...
0
votes
1answer
110 views
Select count of timestamp formatted field in short date format to give number of rows
I have a field titled DTUpdated and it is a timestamp field.
I am trying to select a count of the dates in the rows that are xx old. i.e. 0-3 months, 3-6 months etc.
I am not at the writing date ...
1
vote
1answer
248 views
What value should I choose as length for timestamp without timezone in PostgreSQL?
I'm currently setting up a database to populate it with big data. All the data I get comes from Valve's Steam Web API. Therefore, as all timestamps are returned in Unix timestamps, I cannot directly ...
0
votes
0answers
30 views
Is it possible to record read access to a row?
A table has a creation timestamp column with DEFAULT and an update timestamp column with DEFAULT ... ON UPDATE .... Similar to the ON UPDATE|DELETE ... constraint, we're looking for a way to have a ...
0
votes
2answers
45 views
use of age() function postgres [closed]
I am trying to calculate the time since an event took place. The event timestamp will itself be the result of a MIN aggregate function. Is there a way to do this.
I have run a query to get the ...
0
votes
1answer
262 views
When I set Datestyle to 'SQL, YMD' all queries still return as 'SQL, MDY'
I am working on a database migration from Oracle 12c to Postgresql 12.
We must keep the same date format as the program interacting with this database is written in COBOL and should not be changed.
...
0
votes
0answers
30 views
Fix the timezone of timestamp in MySQL
From my misunderstanding, I stored time as timestamps and thought they were stored as UTC+0. But I moved into a different country and found the timestamps were stored in the local time.
The issue is ...
0
votes
1answer
648 views
In which timezone does psql display "timestamp without timezone"?
What I mean is the following: if I create a timestamp without timezone (timestamp) column and store there some value, internally microseconds are stored, but when issuing select this is converted to a ...
0
votes
1answer
41 views
How can I add timestamp into my table when I use Write-DbaDbTableData?
I am trying to use one table to store the SQL server disk space checking data by dbatools:
$allservers_PRD | Get-DbaDiskSpace | Write-DbaDbTableData -SqlInstance MySQL2019 -Database SQL_DBA_TASK -...
0
votes
1answer
128 views
SQL - Spilt timestamp into multiple rows
I am dealing with data that needs to be looked at on a shift-to-shift basis (8:00:00 to 20:00:00 and its reciprocal are the two shifts) There are instances where a timestamp (one row) will span longer ...
1
vote
0answers
41 views
Correcting wrong timezones/timestamps in existing tables
I did a huge mistake because I didn't know how the TIMESTAMPTZ datatype works in postgresql.
We need to store sensor data from a handful of different sources.
We have a few tables with two timestamp ...
3
votes
1answer
22 views
Using Postgres param in a function
I'm trying to create a few functions to make the SQL queries between my SQLite and Postgres DB's the same.
One thing I would like to do is change a timestamp to a double via a function such as:
create ...
2
votes
1answer
956 views
MySQL Best approach for recording last update timestamp for every column and every row
This question is about possible approaches for time stamping every column of every row in a table.
I have a table with a small number of rows (fewer than 200 and not likely to grow much larger). Each ...
0
votes
0answers
17 views
Column with timestamp datatype not having proper value
I am using PostgreSQL v9.5
A column utime with datatype timestamp without timezone is not having proper values for some rows as given below:
select utime from mytable where utime is not null order by ...
1
vote
1answer
1k views
Postgres epoch from current_timestamp
I've learned that epoch (UNIX timestamp) is a unique independent amount, so I am baffled by output I get from the following queries:
select extract( epoch from current_timestamp::timestamp with time ...
0
votes
1answer
31 views
Querying the most recent records with two fields: datestamp and timestamp
I have a table called airquality that has records for air quality measurements taken on different days and times within those days. These date/timestamps are stored in two different columns: validdate ...
1
vote
1answer
323 views
Timestamp with no time zone - if I'm ok with UTC at all times, is there any downside to using it?
Timestamp with time zone vs timestamp with no time zone.
I'm aware that timestamptz is the same as timestamp no time-zone + (time-zone difference) that gets added upon saving a value in a database. ...
0
votes
3answers
44 views
Convert two integers into timestamp
How do I convert two integers, one for date and one for time, into a timestamp?
Given 20200304 and 1046, return a timestamp for April 3, 2020, 10:46 AM.
Given 20200304 and 946, return a timestamp for ...
0
votes
0answers
80 views
Syntax error around converting timestamps to time
I am writing a function that requires some comparison between the difference date and time parts of the timestamp data type. However it keeps running into syntax errors and I cannot find out what is ...
0
votes
1answer
39 views
Migrating timezone timestamps
I am trying to migrate this node library https://github.com/LocalSEOGuide/lighthouse-reporter from Postgres to MySQL and getting an error error: ER_TRUNCATED_WRONG_VALUE: Incorrect datetime value: '...
0
votes
1answer
44 views
How can I output a legible timestamp from "1583981745.335346" (stored in a 'double' field type) via a select statement?
I have a table within a WordPress installation that stores timestamps in a format that I do not recognize, nor can I figure out how to translate it. In the MySQL database, it appears as "1583981745....
0
votes
1answer
30 views
Can I refuse inserts/updates with timestamps without time-zone in postgresql?
I use exclusively timestamps with time-zone in PostgreSQL, but I just noticed something slightly worrying: If a client inserts/updates a record with a naïve time-stamp, PostgreSQL falls back to a ...
1
vote
1answer
2k views
mongodump command with timestamp query
When I execute the below query in mongodb shell, it gives me the number of records updated after the mentioned timestamp.
db.getCollection('oplog.rs').find({"ts":{"$gt":Timestamp(1582823397,2)}})
I ...
1
vote
0answers
46 views
Storing Large Quantities of Time Series
What is the recommended (type) of database design for storing large amounts of time-series data?
The dataset:
2 million time-series;
Each of the time-series contains around 500 timestamps;
At ...
1
vote
1answer
660 views
Update record with converted epoch timestamp from another column
I'm trying to convert epoch data in one column (timestamp_epoch) to a legitimate timestamp in another column (timestamp) for every record in a table. In reading the PostgreSQL Documentation it ...
2
votes
1answer
262 views
Preserving timezones explicitly in postgres
I've been doing quite some research on different ways of 'seeing' time and how to properly map it in Postgres but I'm still not certain on what to actually use. Several articles recommend or rather ...
4
votes
1answer
1k views
Why mysql throws "invalid default value for field" only when two or more timestamp fields exist in the create statement?
In mysql 5.7.28 I create a table like this:
create table t1 (
id int not null,
d1 timestamp)
engine=innodb;
which works fine and creates d1 as non-null with default value current_timetamp,on update ...
2
votes
2answers
6k views
Add timestamp to field automatically in PostgreSQL
I created a small database in PostgreSQL to manage the data for my thesis. I just started with Postgres, so this is probably a newbie question. I added a column in several tables, that is supposed to ...
