In Table have a Date field of type date and I get 2 date from and to as String.
I want to filter the recodrs that exist between these 2 dates.
What will be the best way to select
The best is to transform the string dates into dates using your DBMS provided transformation functions,
Using Oracle for instance, i would write :
where
your_date_field
between to_date(from,format_of_from) and to_date(to,format_of_to)
Related
I am reading a file from ADLS location, in that one column Period_Ending_Date is having data type as STRING.
The Period_Ending_Date is having many dates in random order, I need to apply filter to get the latest date.
I'm trying this code:
select * from final_table
WHERE Period_Ending_Date = (SELECT MAX(Period_Ending_Date) FROM final_table)
But the problem is I'm getting the day with maximum, not the latest date. I can understand this is happening because of STRING data type. Please guide me how I can change this column to DATE data type or any other alternative to get the solution of this.
I'm working with Scala and SQL on Azure Databricks.
what about changing SELECT MAX(Period_Ending_Date) FROM final_table to SELECT MAX(cast(Period_Ending_Date as date)) FROM final_table - performing explicit casting to date if date format is ISO8601 (YYYY-MM-DD) or using the to_date function (doc) to convert non-standard dates.
I am not getting data between two years, below is between condition
to_char(Wfc.APPLYDTM,'MM/DD/YYYY') between '12/11/2019' and '01/10/2020'
but I am getting data between '12/11/2019' and '12/31/2019' & '01/11/2020' and '01/01/2020' for these dates but not between two different years.
Please help
Try using TO_DATE instead of TO_CHAR, and then compare against valid Oracle date literals:
SELECT *
FROM Wfc
WHERE TO_DATE(APPLYDTM, 'MM/DD/YYYY') BETWEEN date '2019-12-11' AND date '2019-01-10';
Note that if APPLYDTM already be a date, then you don't need to call TO_DATE on it. It doesn't make sense to convert your data to character, if you intend to work with it as a date.
You should convert your data to Date to be able to compare correctly.
The main idea is you should compare date value instead of string value.
to_date(Wfc.APPLYDTM,'MM/dd/yyyy') between to_date('12/11/2019','MM/dd/yyyy') and to_date('01/10/2020','MM/dd/yyyy')
Read here to more details.
Do not convert date/time values to strings! Use the built in functionality.
Your logic is most simply expressed as:
Wfc.APPLYDTMbetween >= DATE '2019-12-11' AND
Wfc.APPLYDTMbetween < DATE '2020-01-11'
Note that the date constants are provided using the DATE keyword. This supposed ISO 8601 standard date formats (happily!).
Also note the use of >= and < rather than BETWEEN. The date data type in Oracle can include a time component -- even if you don't see it when you query the table. This ensures that all date/times are included in the range.
As an added benefit, this can use an index on (APPLYDTMbetween). Using a function usually precludes using an index, unless you have defined a function-based index.
In our oracle DB there are records which are not in a particular date format and I want to select only those record. For example.
Proper data format: dd.mm.yyyy mm:hh:ss
Improper date format: dd.mm.yyyy
Is there any oracle construct to select records based on date format?
Thanks in advance.
If I assume that you are storing dates as a string (a very poor choice), then you can use a regular expression to come very close to what you want:
select (case when regexp_like(col, '^[0-9]{2}[.][0-9]{2}[.][0-9]{4} [0-9]{2}[:][0-9]{2}[:][0-9]{2}$'
then 'okay' else 'bad'
end)
If for some reason you have to store dates as a string, use ISO/ANSI standard formats, such as YYYY-MM-DDTHH:MI:SS.
I am using sql for database connectivity. I am filtering records in database on date basis using sql query which consists of function convert(varchar(100),column name,106). I am comparing it with date having dd/MMM/yyyy format. As a result I get records of next all the dates.
Example: If I try to filter the table by 01/June/2017 then inspite of having records of that date, I get records of next all the dates. I am not able to get records of 01/June/2017.
I have used greater than or equal to expression.
It is better to convert it to this yyyymmdd number format and do the comparison as below:
select convert(int,convert(varchar(10),[your column],112))
20170529
Don't convert your dates into any format (=strings) when doing comparison. Always use the date (or datetime etc) format. That way you will be comparing the actual values, not string or numeric comparison. Here the problem is that format 106 is dd mon yyyy so it will never match your date because it's a string dd/MMM/yyyy but you will get any dates starting with 02 anyhow, for example 02/Jan/1990, because in alphabetical order that will come after your given 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