I'm facing a strange query result and I want to ask you why I'm facing this issue.
I store some datetime data into TestTable as following :
creation_time
-----------------------
2010-07-10 00:01:43.000
2010-07-11 00:01:43.000
2010-07-12 00:01:43.000
This table is created and filled as following :
create table TestTable(creation_time datetime);
Insert into TestTable values('2010-07-10 00:01:43.000');
Insert into TestTable values('2010-07-11 00:01:43.000');
Insert into TestTable values('2010-07-12 00:01:43.000');
when I execute this query , I get two rows only instead of three as I expected:
SELECT * FROM TestTable
WHERE creation_time BETWEEN CONVERT(VARCHAR(10),'2010-07-10',111) -- remove time part
and CONVERT(VARCHAR(10),'2010-07-12',111) -- remove time part
Or if I execute this query , the same issue ..
SELECT * FROM TestTable
WHERE CONVERT(datetime,creation_time,111) BETWEEN CONVERT(VARCHAR(10),'2010-07-10',111) -- remove time part
and CONVERT(VARCHAR(10),'2010-07-12',111) -- remove time part
My Question :
Why the last row ('2010-07-12 00:01:43.000') does not appear in
the result even if I set the date range to cover all the day from 2010-07-10 to 2010-07-12?
I use Sql server 2005 express edition with windows xp 32-bits.
I'm trying to don't use a workaround solution such as increasing the date range to cover additional day to get the days I want.
Thanks .
You need to remove the time part from creation_time as well. Just use the same CONVERT if it works.
Currently you're asking if 2010-07-12 00:01:43.000 is less than 2010-07-12 00:00:00.000, which is not true.
it does not show the date because you have removed the time part, which would make the date equivalent to '2010-07-12 00:00:00.000' and since the last row is greater than this, so it is not displaying in the query results.
Your script should look like this:
SELECT *
FROM TestTable
WHERE creation_time BETWEEN
convert(datetime, convert(char, '2010-07-10', 106))-- remove time part
and **DATEADD**(day, 1, convert(datetime, convert(char, '2010-07-**11**', 106))) -- remove time part and add 1 day
This script will return all between 2010-07-10 00:00:00 and 2010-07-12 00:00:00. Basically this means all items created in 2 days: 2010-07-10 and 2010-07-11.
Converting columns in your table for comparison can be costly and cause indexes to not be used. If you have a million rows in your table and you have an index on creation_time, you will be doing an index scan and converting all million values to a string for comparison.
I find it better to use >= the start date and < (end date + 1 day):
SELECT *
FROM TestTable
WHERE creation_time >= '2010-07-10'
AND creation_time < dateadd(day, 1, '2010-07-12')
And the reason your second one may not work is because format 111 uses slashes ("2010/07/10"), format 120 uses dashes ("2010-07-10"). Your converts aren't doing anything to your start and end date because you are converting a string to varchar, not a date. If you did this, it might work, but I would still recommend not doing the conversion:
SELECT * FROM TestTable
WHERE CONVERT(datetime, creation_time, 111) BETWEEN
CONVERT(VARCHAR(10), CONVERT(datetime, '2010-07-10'), 111) -- remove time part
and CONVERT(VARCHAR(10), CONVERT(datetime, '2010-07-12'), 111) -- remove time part
Date/time inclusive between 7/10/2010 and 7/12/2010:
SELECT * FROM TestTable
WHERE creation_time BETWEEN
CONVERT(VARCHAR,'2010-07-10',101) -- remove time part
and CONVERT(VARCHAR,'2010-07-13',101) -- remove time part
Related
I am working on a dataset that contains car accidents and their time of occurrence. (the data set exists in SQL Server under the name accident).
I have a column that is in date format. I would like to extract the time from the column. Then add a new column called lightining_period label the time as daytime or nighttime. My problem is with setting a range for the times, as I get the wrong label each time I run the code.
Different lighting periods (daytime: 6AM - 5:59PM and nighttime 6PM - 5:59AM).
[1]First I wrote this code to extract the time from accident_date_time and store it in a new column time.
create table lightiningPeriod as
select to_char(accident_date_time,'HH:MMAM') as time
from accident.accident;
[2]Then, I altered the table to add the column lightining_label where I want to store the labels daytime/nighttime.
alter table lightiningPeriod add (
lightining_label varchar2(20)
);
[3]Finally, I used Update statement to change the values of lightining_label according to time ranges. But the tables come out wrong. I tried using between, to_date, cast, convert but none of them worked.
update lightiningPeriod
set lightining_label='daytime'
where time >= '06:00AM'
and time <= '5:59PM';
below is a sample of the output I get which shows wrong labels.
time lightining_label
06:04AM daytime
11:04AM daytime
01:04AM (null)
10:04AM daytime
10:04AM daytime
04:04PM (null)
07:04PM daytime
01:04PM (null)
It looks like the time column is using a string type (VARCHAR, NVARCHAR) instead of TIME. So you compare string values instead of time values.
You can use the following using CONVERT to compare the string values like time values:
UPDATE lightiningPeriod
SET lightining_label = CASE WHEN CONVERT(TIME, [time]) BETWEEN CONVERT(TIME, '06:00AM') AND CONVERT(TIME, '5:59PM') THEN 'daytime' ELSE 'nighttime' END
demo on dbfiddle.uk
I recommend to store the time values on a column using TIME data type.
This is a tweak on Sebastian's answer. In SQL Server, you can use a computed column:
ALTER TABLE lightiningPeriod
ADD lightining_label AS (CASE WHEN CONVERT(TIME, [time]) >= CONVERT(TIME, '06:00:00') AND CONVERT(TIME, [time]) < CONVERT(TIME, '18:00:00')
THEN 'daytime' ELSE 'nighttime'
END)
Then the label is calculated when you query the table, so it is always correct.
Thank you all, I have solved the query doing this:
update lightiningPeriod
set lightining_label='daytime'
where to_char(accident_date_time, 'hh24:mi') >= '06:00'
and to_char(accident_date_time, 'hh24:mi') <= '17:59';
I have Date Column Order_Date In date Time format Isdat
14/05/2018 13:13:06 This is format) , I need To Extract Today's Order before 14:00 P:M 'O' Clock and in Second Column I want to extract order after 15:00 P:M i.e Time from 15:00 P:M till 23:00 P:M in SQL SERVER,
Date Is in 24:00 Hor Format.
In output Order_date Should be 'yyyy-MM-dd hh:mm:ss ' Format
Like the others have said, the first thing you need to do is fix your data; storing a date as a varchar is a bad design choice. Always use a data type that is representative of you data; stores dates as a date, numbers as an int/decimal, etc.
According to the [documentation] there is no style code for dd/MM/yyyy hh:mm:ss, however, a quick SQL as below told me that style code 103 does work:
DECLARE #date varchar(50) = '31/05/2017 19:12:56';
WITH N AS (
SELECT 1 AS i
UNION ALL
SELECT i + 1
FROM N
WHERE I + 1 <= 150)
SELECT I, TRY_CONVERT(datetime2(0),#Date,I) AS Conversion
FROM N
OPTION (MAXRECURSION 150);
So, firstly, let's fix that data of yours. So, let's add the new column in and drop your old one.
ALTER TABLE YourTable ADD OrderDate datetime2(0);
UPDATE YourTable
SET OrderDate = CONVERT(datetime2(0),YourDateColumn,103);
GO
ALTER TABLE YourTable DROP COLUMN YourDateColumn;
EXEC sp_rename 'dbo.YourTable.OrderDate','YourDateColumn','COLUMN';
Ok, now we've got rid of your awful datatype, and got your new column. Good.
Now, you want to specifically query time here; if you're doing that, ideally you want to separate the value of the time and date out. Using something like WHERE CONVERT(time, YourDateColumn) BETWEEN '14:00' AND '15:00' makes the query non-SARGHable. Thus let's use a couple of computed columns for that:
ALTER TABLE YourTable ADD OrderDate AS CONVERT(date, YourDateColumn);
ALTER TABLE YourTable ADD OrderTime AS CONVERT(time, YourDateColumn);
Now, to your question at hand: "I need To Extract Today's Order before 14:00 P:M 'O' Clock and in Second Column I want to extract order after 15:00 P:M i.e Time from 15:00 P:M till 23:00 P:M in SQL SERVER". honestly, this is non-sensical; putting different orders based on time in different columns? I have no idea what you mean here, I'm afraid, and I have no sample data or expected results to work with. Thus, instead, i'll show you how to return orders after 14:00 but before '15:00` on a specific date:
SELECT *
FROM YourTable YT
WHERE OrderDate = '20170515'
AND OrderTime >= '14:00'
AND OrderTime < '15:00';
If you need more detail than that, you have a lot of comments asking you for more detail; I suggest you have a look at those. :)
I have date formats that are as follows:
Date_str
19-12-2007
31-7-2009
3-1-2010
31-11-2009
etc.
I can't do the following:
CONCAT(RIGHT(Date_str,4),SUBSTRING(Date_str,3,3),LEFT(2))
because as you can see above, the dates are not the same length. Is there a way in SQL Server to extract the date as datetime/date?
I also tried
Convert(datetime, Date_str)
but it just threw an error:
The conversion of a varchar data type to a datetime data type resulted
in an out-of-range value.
If 2012+, I would use Try_Convert(). This will return bogus dates as NULL.
Example
Declare #YourTable Table ([Date_str] varchar(50))
Insert Into #YourTable Values
('19-12-2007')
,('31-7-2009')
,('3-1-2010')
,('31-11-2009')
Select *
,try_convert(date,Date_Str,105)
from #YourTable
Returns
Date_str (No column name)
19-12-2007 2007-12-19
31-7-2009 2009-07-31
3-1-2010 2010-01-03
31-11-2009 NULL -- Notice 11/31 is NOT a date
See https://learn.microsoft.com/en-us/sql/t-sql/functions/cast-and-convert-transact-sql for date formats
You probably need
CONVERT(DateTime, Date_str, 105)
As I mentioned in the comments, the only realistic solution is to convert that string into a proper date-typed column. The current format doesn't allow date sorting, or search for a range of dates, eg to find entries in the last week, or between one date and the other.
Parsing with CONVERT or TRY_PARSE means that no indexes can be used to speed up queries. Each time :
WHERE CONVERT(Date, Date_str, 105) > '20170101'
is used, the server will have to scan the entire table to convert the data, then filter the rows.
If you can't change the type of the field itself, you can create a persisted computed column that returns the value as a date and add indexes to it. You'll be able to use that column for indexed querying:
alter table SomeTable add date2 as TRY_convert(Actual_Date,date_str,105) PERSISTED
create index IX_SomeTable_ActualDate on SomeTable (Actual_Date)
This will allow you to perform sorting without tricks:
SELECT *
FROM SomeTable
ORDER BY Actual_Date
Or run range queries that take advantage of the IX_SomeTable_ActualDate index:
SELECT *
FROM SomeTable
Where Actual_Date Between DATEADD(d,-7,GETDATE()) AND GETDATE()
If you have 1000 rows, you could get 1000 times better performance.
Existing applications won't even notice the change. Newer queries and applications will be able to take advantage of indexing and sorting
I had a similar problem: my column (<my_date_field>) had date values in the form of
2021-01
2021-02
2021-10
2021-12
and so on, with data type of nvarchar(4000), and I always ran into the Conversion failed when converting date and/or time from character string. error (when trying e.g. CAST(<my_date_field> AS DATE) or CAST(CAST(<my_date_field> AS VARCHAR(7)) AS DATE) etc.)
I was able to convert them to date with the following code:
SELECT
CONVERT(date, <my_date_field> + '-01') AS first_day_of_month
FROM my_table
which resulted in
2021-08-01
2021-07-01
2021-06-01
2021-05-01
I'm using SQL Server 2012 and I need to write a query that will extract data greater than a particular date. The date field is called 'CreatedOn" and dates are recorded in this format "2014-08-18 17:02:57.903".
Currently, the date part of my query stands as follows:
WHERE CreatedOn > '2014-08-18'
Problem is extracted data includes those of '2014-08-18'. It's like the > (greater than) is acting like >= (greater than or equal)!
How should I write my query if I need all data, say greater than '2014-08-18'?
Try the following condition. The problem is that 2014-08-18 is really 2014-08-18 00:00:00 (includes the hour), so any date time in that day will be greater.
WHERE CreatedOn >= '2014-08-19'
'2014-08-18' actually means '2014-08-18 00:00:00'
So if you do not want 18th you should put either '2014-08-19' or specify the hours you want your date to be bigger of.
As the others have said it is actually translating to CreatedOn > 2014-08-18 00:00:00
Instead try converting your datetime field to a short ate and compare those.
The 126 in Convert maps to the yyyy-mm-ddThh:mi:ss.mmm format.
WHERE CONVERT(char(10), CreatedOn,126) > '2014-08-18'
It sounds like when you're saying you want records "greater than '2014-08-18' you actually mean "records that occurred past 2014-08-18 23:59:59.999999" - you have to take into account time when working with dates, unless the time is otherwise removed (which in your sample data it was not.
You could do something like the following:
declare #gtDate datetime
set #gtDate = dateadd(d, 1, convert(datetime,convert(varchar(10), '2014-08-18', 101)))
....
WHERE CreatedOn >= #gtDate
Here we're taking your '2014-08-18', convert it to a varchar containing only the date (to help in case '2014-08-18' is ever '2014-08-18 12:00:00 as an example)
Then we convert the varchar back to a date, and add a day to it. In the end the statement says
Give me records that occured on 2014-08-19 or greater
EDIT:
Here's a fiddle demonstrating
http://sqlfiddle.com/#!6/90465/1
Note that we have 4 rows of data potential
insert into sampleData (Created)
select '2014-08-17'
union all select '2014-08-18'
union all select '2014-08-18 12:00:00'
union all select '2014-08-19'
union all select '2014-08-19 15:00:00'
only the bottom 2 rows (2014-08-19 and 2014-08-19 15:00:00) would be returned
I am looking for a way to select a whole days worth of data from a where statement. Timestamp is in unix time such as (1406045122). I want to select the today's date of unix time range and find all the food that has been added in today. Thank in advance. This is the code I wrote. I'm not sure what I should put in the ( ????? ) part. I know it has to do with 60*60*24=86400 secs per day but I'm not too sure how I can implement this.
Select timestamp,food from table1 where timestamp = ( ????? );
Select timestamp,food
FROM table1
WHERE timestamp > :ts
AND timestamp <= (:ts + 86400);
replace :ts with the starting timstamp and you'll filter a whole day's worth of data
edit
This select query would give you the current timestamp (there may be more efficient ones, i don't work with sqlite often)
select strftime("%s", current_timestamp);
You can find more info about them here: http://www.tutorialspoint.com/sqlite/sqlite_date_time.htm
Using the strftime() function, combined with the date() function we can write this following query which will not need any manual editing. It will return the records filtered on timestamp > start of today & timestamp <= end of today.
Select timestamp,food
FROM table1
WHERE timestamp > strftime("%s", date(current_timestamp))
AND timestamp <= (strftime("%s", date(current_timestamp)) + 86400);
Your mileage will likely depend on your version of SQL but for example on MySQL you can specify a search as being BETWEEN two dates, which is taken conventionally to mean midnight on each. So
SELECT * FROM FOO WHERE T BETWEEN '2014-07-01' AND '2014-07-02';
selects anything with a timestamp anywhere on 1st July 2014. If you want to make it readable you could even use the ADDDATE function. So you could do something like
SET #mydate = DATE(T);
SELECT * FROM FOO WHERE T BETWEEN #mydate AND ADDDATE(#mydate, 1);
The first line should truncate your timestamp to be 00:00:00. The second line should SELECT only records from that date.