I have 2 tables which I want to join based on date but date format present in both of them is different.
In one table date is mentioned as 10-10-2020 and in other it is 10-Oct-20. My preferred format would be 10-10-2020 or 10/10/2020.
How can this be achieved using SQL Server?
If possible, change the column that has the "oct" version to the same type as the first one or a date column. This will make the join easier since its not required to transform each row.
If that is not possible you need a hardcoded translation for the (I assume) 12 different Strings describing the months to the equivalent number 1-12. That will allow you to replace the "oct" part with a number. Then you should be able to use cast( as date) to make it a proper Date column.
You can simply use the try_cast() function as shown below:
select try_cast('10-Oct-20' as date)
The output will be as shown below:
DtDate
-----------
2020-10-10
For displaying the date in different format you can use one of the method as suggested in this link.
For simplicity see the below query:
select convert(varchar(10), try_cast('10-Nov-20' as date), 10)
select convert(varchar(10), try_cast('10-Nov-20' as date), 5)
Related
I'm using PostgreSQL, but this question is for any modern dbms
I want to basically convert a datetime column which has yyyy/mm/dd into just yyyy/mm
I tried getting months and year separately and using Concat, but the problem is the month comes as a single digit integers for values < 10 and that messes up ordering
select *,
concat(date_part('year' , date_old), '/', date_part('month' , date_old)) as date_new
from table
date _old
date_new
2010-01-20
2010-1
2010-01-22
2010-1
2010-11-22
2010-11
You can use to_char()
to_char(date_old, 'yyyy/mm')
If you want to display your date in the format YYYY-MM then
In PostgreSQL (db<>fiddle) and Oracle (db<>fiddle), use TO_CHAR:
SELECT TO_CHAR(date_old, 'YYYY/MM') FROM table_name;
In MySQL (db<>fiddle), use DATE_FORMAT:
SELECT DATE_FORMAT(date_old, '%Y/%m') FROM table_name;
In SQL Server (db<>fiddle), use CONVERT or, if you are using SQL Server 12 or later, FORMAT:
SELECT CONVERT(varchar(7), date_old, 111) FROM table_name;
SELECT FORMAT(date_old,'yyyy/MM') FROM table_name;
Don't do this.
If you're able to use the date_part() function, what you have is not actually formatted as the yyyy/mm/dd value you say it is. Instead, it's a binary value that's not human-readable, and what you see is a convenience shown you by your tooling.
You should leave this binary value in place!
If you convert to yyyy/mm, you will lose the ability to directly call functions like date_part(), and you will lose the ability to index the column properly.
What you'll have left is a varchar column that only pretends to be a date value. Schemas that do this are considered BROKEN.
When I write below query it gives record .
SELECT [srno],[order_no],[order_date],[supplier_name],[item_code],[item_name],[quntity]
FROM [first].[dbo].[Purchase_Order]
WHERE order_date BETWEEN '22/04/2015' AND '4/05/2015'
In this query if I don't add 0 in '4/05/2015' it returns record.
But when I add 0 to the date i.e. '04/05/2015' it doesn't give any records.
SELECT [srno],[order_no],[order_date],[supplier_name],[item_code],[item_name],[quntity]
FROM [first].[dbo].[Purchase_Order]
WHERE order_date BETWEEN '22/04/2015' AND '04/05/2015'
The reason it's not working because SQL is trying to do a string comparison because both your types are string types, But what you really want to do a date comparison.
You should do something like this. Since you only need date part you can strip off the time and use style 103 for your format dd/mm/yyyy.
WHERE CONVERT(DATETIME,LEFT(order_date,10),103)
BETWEEN CONVERT(DATETIME,'20150422') AND CONVERT(DATETIME,'20150504')
Alternately you can use this as well if your order_date has dates like this 5/4/2015 03:20:24PM
WHERE CONVERT(DATETIME,LEFT(order_Date,CHARINDEX(' ', order_Date) - 1),103)
BETWEEN CONVERT(DATETIME,'20150422') AND CONVERT(DATETIME,'20150504')
A long term solution is to change your column order_date to DATE/DATETIME
It Better to Cast it to date rather than depend on IMPLICIT conversion
SELECT [srno],[order_no],[order_date],[supplier_name],[item_code],
[item_name],[quntity] FROM [first].[dbo].[Purchase_Order] where
convert(date,order_date,105) BETWEEN cast('22/04/2015' as Date) AND cast('04/05/2015' as date)
I have a table named book_data with batch_dt as column name of type varchar in sql server.
when I pass the query
SELECT DISTINCT batch FROM book_data
it gives me the following results
batch_dt
-------------
2012-10-31
-------------
2012-11-01
-------------
2012-11-02
-------------
2012-11-03
-------------
.
.
.
Now what I am doing is getting the total count of records between two dates. Fairly a simple query.
SELECT COUNT(*) FROM book_data WHERE CONVERT(varchar(12),CONVERT(datetime,batch_dt),101) BETWEEN '11/02/2012' and '10/31/2012'
the result is
112
and just by changing the month from 02 to 2 the query gives me 218 results
SELECT COUNT(*) FROM book_data WHERE CONVERT(varchar(12),CONVERT(datetime,batch_dt),101) BETWEEN '11/2/2012' and '10/31/2012'
why this different behaviour?
Use CAST(batch_dt AS DATE) instead, and pass the date in a language neutral manner, in the format YYYYMMDD. This way it will be comared as a date not as a varchar:
SELECT COUNT(*)
FROM book_data
WHERE CAST(batch_dt AS DATE)
BETWEEN '20121102' and '20121130'
But, this is not safe, if there was any value in barch_dt in a wrong format, you will get a casting error. In this case you can add ISDATE(batch_dt) = 1 to ensure that it is a valid data time. But it is better to make this column of datatype DateTime.
Another thing to note: is that BETWEEN is asymmetric in SQL Server, meaning that BETWEEN '11/02/2012' and '10/31/2012' is evaluated as:
DATE >= '11/02/2012'
AND
DATE <= '10/31/2012'
which will never be true, the reason it works for you is that the dates were be compared as strings not as a dates. But you have to keep it like BETWEEN the small value and the biggest value.
You compare string with BETWEEN. If you do so you need to make sure that you compare in the correct order => YYYYMMDD MM:SS would be a correct order.
If you can, add columns with type datetime and store real date time values in your database. If you can not do that you can split up the values and build a date value yourself. This is much slower then just use a CONVERT() or CAST() but you can make sure that it works even with wrong date-strings.
You can use PATINDEX(),LEFT(),RIGHT() keywords to get the values you need or you use a split() function (you can find many version google it, e.g. https://codereview.stackexchange.com/questions/15125/sql-server-split-function-optimized). If you use the split function, then split by / and then get year, month, day from the positions.
But best would be still to have correct datetime values stored in your db.
You get this different behavior because you don't compare the dates but the strings/varchars.
For a Date (or DateTime), 10/2/2012 is the same as 10/02/2012.
But for string, these values are (of course) different. It's just as if you'd compare 'abcd' with 'ab0cd'
SELECT COUNT(*)
FROM book_data
WHERE CONVERT(DATETIME,batch_dt,101) BETWEEN '11/2/2012' and '10/31/2012'
This would be more appropriate
I am using MS SQLServer and trying to insert a month/year combination to a table like this:
INSERT INTO MyTable VALUES (1111, 'item_name', '9/1998')
apparently, the above command cannot work since
Conversion failed when converting date and/or time from character string.
Because 9/1998 is a bad format. I want to fix this and this column of the table will show something like:
9/1998
12/1998
(other records with month/year format)
...
Can someone help me with this?
thank you
SQL Server only supports full dates (day, month, and year) or datetimes, as you can see over on the MSDN data type list: http://msdn.microsoft.com/en-us/library/ff848733(v=sql.105).aspx
You can use a date value with a bogus day or store the value as a string, but there's no native type that just stores month/year pairs.
I see this is an old post but my recent tests confirm that storing Date or splitting the year and month to two columns (year smallint, month tinyint) results in the overall same size.
The difference will be visible when you actually need to parse the date to the filter you need (year/month).
Let me know what do you think of this solution! :)
Kind regards
You can just use "01" for the day:
INSERT INTO MyTable VALUES (1111, 'item_name', '19980901')
You can:
1) Change the column type to varchar
2) Take the supplied value and convert it to a proper format that sql server will accept before inserting, and format it back to 'M/YYYY' format when you pull the data: SELECT MONTH([myDate]) + '/' + YEAR([myDate]) ...
You may want to consider what use you will have for your data. At the moment, you're only concerned with capturing and displaying the data. However, going forward, you may need to perform date calculations on it (ie, compare the difference between two records). Because of this and also since you're about two-thirds of the way there, you might as well convert this field to a Date type. Your presentation layer can then be delegated with the task of displaying it appropriately as "MM/yyyy", a function which is available to just about any programming language or reporting platform you may be using.
if you want use date type, you should format value:
declare #a date
SELECT #a='2000-01-01'
select RIGHT( convert (varchar , #a, 103), 7) AS 'mm/yyyy'
if you want make query like SELECT * FROM...
you should use varchar instead date type.
The task:
I need to count every record in a table that was added after 07/01/2011.
Info:
There is a column in the table "Date_added" which is formatted as varchar and contains dates in format mm/dd/yyyy.
What I've tried:
I tried the following query:
SELECT count(date_added) FROM Abatements_Doc WHERE date_added >= '07/01/2011'
Unfortunately it counted any date where the month was greater than 07 regardless of the year or day. I'm at a loss as to how I should format my query to get it to read the dates properly instead of by ascii sort. In my research I discovered the CAST and CONVERT options, but am not sure how to use them, or which one I should use if any. I'm extremely new to SQL, and want to make sure I don't mess up the data in the table. I just need to get the count as specified above without altering the data in the table in any way. Any help in this regard will be very much appreciated. Thanks in advance.
I didn't test. But try convert statement.
SELECT count(date_added)
FROM Abatements_Doc
WHERE convert(datetime,date_added,1) >= convert(datetime,'07/01/2011',1)
(1) don't use mm/dd/yyyy as your date format. Use a safe and unambiguous format; the only one I trust for DATETIME/SMALLDATETIME is YYYYMMDD.
(2) change the data type in your table to DATETIME/SMALLDATETIME/DATE depending on accuracy required. Then `WHERE date_added >= '20110701' will work just fine (and will use an index on that column, if one exists).
(3) if you can't change the data type, then the following will work just fine as well (though no index will be used):
WHERE CONVERT(DATETIME, date_added, 101) >= '20110701'
Varchar can't be compared, try changing your column to date type.
Convert both date_added column values and your target date to DATETIME and compare; as in:
SELECT COUNT(1)
FROM Abatements_Doc
WHERE (CONVERT(datetime, date_added, 101)) >= CONVERT('07/01/2011', date_added, 101))