I have a table with tasks for specified users.
The columns are:
TASK_ID
TASK_NAME
TIME_FROM
TIME_TO
USER_id
I want to create a report that will show tasks for current day, sorted by start time.
But I dont know how to implement comparing task days with sysdate without comparing hours. I want to show on repport tasks for all hours of current day. How can I do that?
Assuming that "tasks for current day" means any task with a time_from of some time today and that time_from and time_to are both date data types
SELECT *
FROM your_table
WHERE trunc(task_from) = trunc(sysdate)
ORDER BY task_from
trunc( <<date>> ) returns <<date>> at midnight. So trunc(sysdate) returns today at midnight. And trunc(task_from) will equal trunc(sysdate) for any date whose day component is today regardless of the time.
From a performance standpoint, a function-based index on trunc(task_from) would likely be beneficial.
Alternately, if task_from is indexed, it may be beneficial to this instead
SELECT *
FROM your_table
WHERE task_from >= trunc(sysdate)
AND task_from < trunc(sysdate+1)
ORDER BY task_from
so that Oracle can do an index scan on task_from.
Related
I am running the below query to get data recorded in the past 24 hours. I need the same data recorded starting midnight (DATE > 12:00 AM) and also data recorded starting beginning of the month. Not sure if using between will work or if there is better option. Any suggestions.
SELECT COUNT(NUM)
FROM TABLE
WHERE
STATUS = 'CNLD'
AND
TRUNC(TO_DATE('1970-01-01','YYYY-MM-DD') + OPEN_DATE/86400) = trunc(sysdate)
Output (Just need Count). OPEN_DATE Data Type is NUMBER. the output below displays count in last 24 hours. I need the count beginning midnight and another count starting beginning of the month.
The query you've shown will get the count of rows where OPEN_DATE is an 'epoch date' number representing time after midnight this morning*. The condition:
TRUNC(TO_DATE('1970-01-01','YYYY-MM-DD') + OPEN_DATE/86400) = trunc(sysdate)
requires every OPEN_DATE value in your table (or at least all those for CNLD rows) to be converted from a number to an actual date, which is going to be doing a lot more work than necessary, and would stop a standard index against that column being used. It could be rewritten as:
OPEN_DATE >= (trunc(sysdate) - date '1970-01-01') * 86400
which converts midnight this morning to its epoch equivalent, once, and compares all the numbers against that value; using an index if there is one and the optimiser thinks it's appropriate.
To get everything since the start of the month you could just change the default behaviour of trunc(), which is to truncate to the 'DD' element, to truncate to the start of the month instead:
OPEN_DATE >= (trunc(sysdate, 'MM') - date '1970-01-01') * 86400
And the the last 24 hours, subtract a day from the current time instead of truncating it:
OPEN_DATE >= ((sysdate - 1) - date '1970-01-01') * 86400
db<>fiddle with some made-up data to get 72 back for today, more for the last 24 hours, and more still for the whole month.
Based on your current query I'm assuming there won't be any future-dated values, so you don't need to worry about an upper bound for any of these.
*Ignoring leap seconds...
It sounds like you have a column that is of data type TIMESTAMP and you only want to select rows where that TIMESTAMP indicates that it is today's date? And as a related problem, you want to find those that are the current month, based on some system values like CURRENT TIMESTAMP and CURRENT DATE? If so, let's call your column TRANSACTION_TIMESTAMP instead of (reserved word) DATE. Your first query could be:
SELECT COUNT(NUM)
FROM TABLE
WHERE
STATUS = 'CLND'
AND
DATE(TRANSACTION_TIMESTAMP)=CURRENT DATE
The second example of finding all for the current month up to today's date could be:
SELECT COUNT(NUM)
FROM TABLE
WHERE
STATUS = 'CLND'
AND
YEAR(DATE(TRANSACTION_TIMESTAMP)=YEAR(CURRENT DATE) AND
MONTH(DATE(TRANSACTION_TIMESTAMP)=MONTH(CURRENT DATE) AND
DAY(DATE(TRANSACTION_TIMESTAMP)<=DAY(CURRENT DATE)
I'm working on a project with a db that contains a date column for patient visits in the format of %m-%d-yyyy and need to sort so that it only pulls the rows where that date is within the last two weeks. I've tried a few different functions of convert, to_date, and can't seem to get anything to work.
I'm still very new to SQL and I don't know if this is a special case because I'm working with an oracle db
Not the full code, because it has dozens of queries and multiple joins (would that affect the date syntax?) but this is the format I'm trying for...
create table "Visits"
insert into "Visits" (
'John Doe',
'5/24/2021',
'Story about the visit',
'More room for story if needed')
select
"User_Name",
"Visit_Date",
"Visit_Narrative",
"Visit_Narrative_Overflow"
from "Visits"
where "Visits"."Visit_Date" >= TRUNC(SYSDATE) - 14
I'm working on a project with a db that contains a date column for patient visits in the format of %m-%d-yyyy
No, you don't have it in the format mm.dd.yyyy. A DATE data type value is stored within the database as a binary value in 7-bytes (representing century, year-of-century, month, day, hour, minute and second) and this has no format.
need to sort so that it only pulls the rows where that date is within the last two weeks.
You want a WHERE filter:
If you want to have the values that happened in the last 14 days then TRUNCate the current date back to midnight and subtract 14 days:
SELECT visit_date
FROM patient
WHERE visit_date >= TRUNC(SYSDATE) - INTERVAL '14' DAY
or
SELECT visit_date
FROM patient
WHERE visit_date >= TRUNC(SYSDATE) - 14
(or subtract 13 if you want today and 13 days before today.)
If you want it after Monday of last week then TRUNCate to the start of the ISO Week (which is always a Monday) and subtract 7 days:
SELECT visit_date
FROM patient
WHERE visit_date >= TRUNC(SYSDATE, 'IW') - INTERVAL '7' DAY
I ended up figuring it out based on an answer from another forum (linked below);
it appears that my original to_date() was incomplete without a second and operator in my where clause. This code is working perfectly
select
"User_Name",
"Visit_Date",
"Visit_Narrative",
"Visit_Narrative_Overflow"
from "SQLUser"."Visits"
where "SQLUser"."Visits"."Visit_Date" >= to_date('5/10/2021', 'MM/DD/YYYY')
and "SQLUser"."Visits"."Visit_Date" < to_date('5/24/2021', 'MM/DD/YYYY')
I want to create a query in Oracle SQL that will grab records from a given time interval, during certain hours of the day, e.g. records between 10am to noon, in the past 10 days. I tried this, but it does not work:
select * from my_table where timestamp between
to_timestamp('2020-12-30','YYYY-MM-DD')
and
to_timestamp('2021-01-08','YYYY-MM-DD') and
timestamp between
to_timestamp('10:00:00','HH24:MI:SS')
and
to_timestamp('12:00:00','HH24:MI:SS')
where timestamp is of type TIMESTAMP. I have also thought of using a join, but I am struggling to find a way to filter on time of day.
Is there a way to filter using only the time, not the date, or a way to filter on time for every day in the interval?
select *
from my_table
where timestamp between to_timestamp('2020-12-30','YYYY-MM-DD')
and to_timestamp('2021-01-08','YYYY-MM-DD')
and timestamp - trunc(timestamp) between interval '10' hour
and interval '12' hour
If you don't need to include exactly noon (including no fractional seconds), you could also do
select *
from my_table
where timestamp between to_timestamp('2020-12-30','YYYY-MM-DD')
and to_timestamp('2021-01-08','YYYY-MM-DD')
and extract( hour from timestamp ) between 10 and 11
As an aside, I'd hope that your actual column name isn't timestamp. It's legal as a column name but it is a reserved word so you're generally much better off using a different name.
select * from accounts where sysdate - 100 < last_active_dt;
select * from accounts where sysdate - 100 <= last_active_dt;
Both of the queries returned the same result.
I was thinking that for the first query, it would not select
records on the day of last_active_dt. For the 2nd query, it
will select records on the day of last_active_dt.
But this does not seem to be the case as both returned the same results.
Is there any difference to it? And how can I see the difference?
last_active_dt column follows a date format DD-MON-YYYY
last_active_dt column follows a date format DD-MON-YYYY
No, it doesn't (but it may look like it does in the user interface you are using).
A DATE data type always has year, month, day, hour, minute and second components and is stored (without any formatting) in 7 bytes. It is the user interface that applies a (default) format to the date and this may hide the time component from you.
You can use:
ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS';
To change the default date format used in SQL*Plus (and SQL Developer) to see the date with all the components.
Equally, SYSDATE is of a DATE data type and has year, month, day, hour, minute and second components so what you are probably intending is:
select * from accounts where TRUNC( sysdate ) - INTERVAL '100' DAY < last_active_dt;
This will get all the columns where the last_active_dt is after midnight of the day 100 days ago (even if it 1 second after). This will work if all your last_active_dt values have the times TRUNCated to exactly midnight 00:00:00 but not if the column as non-zero time components as you will still get values with times from 00:00:01 to 23:59:59 of the day 100 days ago.
If your last_active_dt has a non-zero time component then you want:
select * from accounts where TRUNC( sysdate ) - INTERVAL '99' DAY <= last_active_dt;
My app has a Events table with time-stamped events.
I need to report the count of events during each of the most recent N time intervals. For different reports, the interval could be "each week" or "each day" or "each hour" or "each 15-minute interval".
For example, a user can display how many orders they received each week, day, or hour, or quarter-hour.
1) My preference is to dynamically do a single SQL query (I'm using Postgres) that groups by an arbitrary time interval. Is there a way to do that?
2) An easy but ugly brute force way is to do a single query for all records within the start/end timeframe sorted by timestamp, then have a method manually build a tally by whatever interval.
3) Another approach would be add separate fields to the event table for each interval and statically store an the_week the_day, the_hour, and the_quarter_hour field so I take the 'hit' at the time the record is created (once) instead of every time I report on that field.
What's best practice here, given I could modify the model and pre-store interval data if required (although at the modest expense of doubling the table width)?
Luckily, you are using PostgreSQL. The window function generate_series() is your friend.
Test case
Given the following test table (which you should have provided):
CREATE TABLE event(event_id serial, ts timestamp);
INSERT INTO event (ts)
SELECT generate_series(timestamp '2018-05-01'
, timestamp '2018-05-08'
, interval '7 min') + random() * interval '7 min';
One event for every 7 minutes (plus 0 to 7 minutes, randomly).
Basic solution
This query counts events for any arbitrary time interval. 17 minutes in the example:
WITH grid AS (
SELECT start_time
, lead(start_time, 1, 'infinity') OVER (ORDER BY start_time) AS end_time
FROM (
SELECT generate_series(min(ts), max(ts), interval '17 min') AS start_time
FROM event
) sub
)
SELECT start_time, count(e.ts) AS events
FROM grid g
LEFT JOIN event e ON e.ts >= g.start_time
AND e.ts < g.end_time
GROUP BY start_time
ORDER BY start_time;
The query retrieves minimum and maximum ts from the base table to cover the complete time range. You can use an arbitrary time range instead.
Provide any time interval as needed.
Produces one row for every time slot. If no event happened during that interval, the count is 0.
Be sure to handle upper and lower bound correctly. See:
Unexpected results from SQL query with BETWEEN timestamps
The window function lead() has an often overlooked feature: it can provide a default for when no leading row exists. Providing 'infinity' in the example. Else the last interval would be cut off with an upper bound NULL.
Minimal equivalent
The above query uses a CTE and lead() and verbose syntax. Elegant and maybe easier to understand, but a bit more expensive. Here is a shorter, faster, minimal version:
SELECT start_time, count(e.ts) AS events
FROM (SELECT generate_series(min(ts), max(ts), interval '17 min') FROM event) g(start_time)
LEFT JOIN event e ON e.ts >= g.start_time
AND e.ts < g.start_time + interval '17 min'
GROUP BY 1
ORDER BY 1;
Example for "every 15 minutes in the past week"`
Formatted with to_char().
SELECT to_char(start_time, 'YYYY-MM-DD HH24:MI'), count(e.ts) AS events
FROM generate_series(date_trunc('day', localtimestamp - interval '7 days')
, localtimestamp
, interval '15 min') g(start_time)
LEFT JOIN event e ON e.ts >= g.start_time
AND e.ts < g.start_time + interval '15 min'
GROUP BY start_time
ORDER BY start_time;
Still ORDER BY and GROUP BY on the underlying timestamp value, not on the formatted string. That's faster and more reliable.
db<>fiddle here
Related answer producing a running count over the time frame:
PostgreSQL: running count of rows for a query 'by minute'