How to Use Between Clause in Sql query without using and clause - sql

I have created a query which gets results between 2 dates, Its working fine..
Now i have a scenario in which users does not enter any date..In this case
I need to fetch all the result from database regardless of date..
The following query fails when user does not enter any date, it returns
empty result set.
Kindly guide me how to resolve this problem.
select * from emp_register
where date between ' 2015-03-26 15:42:52' and ' 2015-03-26 15:42:52'
or status= 'Y'
Date Format is Timestamp

where date between ' 2015-03-26 15:42:52' and ' 2015-03-26 15:42:52'
' 2015-03-26 15:42:52' is NOT a DATE, it is a string. Never ever rely on implicit data type conversion. You might just be lucky to get the result depending on your NLS settings, however, it will certainly fail when the client NLS settings will be different for others.
Now i have a scenario in which users does not enter any date..In this case I need to fetch all the result from database regardless of date
No need to do in PL/SQL, do it in SQL.
Use NVL function on the values. Use a default lower bound and upper bound date values in the BETWEEN clause for the NVL.
For example,
SELECT *
FROM emp_register
WHERE DATE BETWEEN NVL(:date1, DATE '1900-01-01') AND NVL(:date2, DATE '9999-01-01')
OR status= 'Y'
So, whenever :date1 and/or :date2 and/is NULL, then it would use the default date values to fetch all the rows from the table.

There are couple of options:
Using Dynamic SQL to build your queries based on user input
Using multiple IF/ELSE statements to build your query based on user input
Setting default values for start and end dates that would always fit in your time range, such as 1900-01-01 and 2300-01-01 if user didn't pass any.

Related

Access query with date BETWEEN breaks when using parameters

I have an SQL query in access that will grab all records where a calculated date is in between two values. It works fine if I hardcode date literals such as:
SELECT *
FROM Table
WHERE DateAdd("d",-60,DateAdd("yyyy",65,[Table].[BirthDate])) Between #3/21/2021# And #3/27/2021#;
However I need to parametrize the the between dates so that they can be entered by a user like:
SELECT *
FROM Table
WHERE DateAdd("d",-60,DateAdd("yyyy",65,[Table].[BirthDate])) Between [StartDate] And [EndDate];
However when I run the latter query and enter the exact same dates as the former, hard-coded one, it starts pulling records outside the between range. I've attempted to enter the dates like 3/21/2021 as well as date literals like #3/21/2021# and neither work. The latter doesn't pull anything at all.
I also have a form with a handful of text boxes using the short date format that let the user pick the dates for the query. It has the same issue of pulling back incorrect records. None of the records have any time component to my knowledge.
How can I get the date between to correctly work with user entered parameters?
Access doesn't know what data type your parameters are, so specify that in the query:
PARAMETERS
StartDate DateTime,
EndDate DateTime;
SELECT
*
FROM
Table
WHERE
DateAdd("d",-60,DateAdd("yyyy",65,[Table].[BirthDate])) Between [StartDate] And [EndDate];
Parameters worked to filter a native field - not the calculated date. However, using CDate() function worked.
SELECT *
FROM Table
WHERE DateAdd("d",-60,DateAdd("yyyy",65,[Table].[BirthDate]))
Between CDate([StartDate]) And CDate([EndDate]);
But before I remembered that, I tested calculating with inputs back to a birthdate range which also worked.
SELECT *
FROM Table
WHERE [BirthDate] Between DateAdd("d",60,DateAdd("yyyy",-65,[StartDate]))
And DateAdd("d",60,DateAdd("yyyy",-65,[EndDate]));

PeopleSoft Query and date prompts

I have a PS Query and one of its prompts is ADM_CREATION_DT where the condition is:
This is a FROM date. All records starting from the selected date to the current date will be included in the report. Leaving this blank will default this to the current date.
I'm quite lost how to put this in the criteria.
part where Invalid datatype error happens
I think you can make a decode expression and make the date sysdate if the prompt value is empty.
decode(:1,NULL,sysdate,:1)
here are some search results for: ps query decode prompt sysdate
https://peoplesoftexperts.blogspot.com/2007/12/how-to-default-sysdate-current-date-for.html
https://it.toolbox.com/question/optional-prompt-for-date-in-ps-query-082912
http://www.psoftsearch.com/optional-prompting-ps-query/
Looking at the search results above, you may need to do a TO_CHAR on the date field. If so, I would look at other dates in the SELECT clause of the SQL generated by PS Query and use the same format they do.

DB2 Convert Number to Date

For some reason (I have no control over this) dates are stored as Integers in an iSeries AS400 DB2 system that I need to query. E.g. today will be stored as:
20,171,221
Being in the UK I need it to be like the below in Date format:
21/12/2017
This is from my query: (OAORDT = date field)
Select
Date(SUBSTR( CHAR( OAORDT ),7,2) ||'/' || SUBSTR(CHAR ( OAORDT ),5,2) || '/' || SUBSTR(CHAR (OAORDT ),1,4)) AS "Order Date"
from some.table
However, all I get is Nulls. If I remove the Date function, then it does work but its now a string, which I don't want:
Select
SUBSTR( CHAR( OAORDT ),7,2) ||'/' || SUBSTR(CHAR ( OAORDT ),5,2) || '/' || SUBSTR(CHAR (OAORDT ),1,4) AS "Order Date"
from some.table
How do I convert the OAORDT field to Date?
Just to update - I will be querying this from MS SQL Server using an OpenQuery
Thanks.
1) How do I convert the OAORDT field to Date?
Simplest is to use TIMESTAMP_FORMAT :
SELECT DATE(TIMESTAMP_FORMAT(CHAR(OAORDT),'YYYYMMDD'))
2) Being in the UK I need it to be [...] in Date format 21/12/2017 :
SELECT VARCHAR_FORMAT(DATE(TIMESTAMP_FORMAT(CHAR(OAORDT),'YYYYMMDD')),'DD/MM/YYYY')
Note, you didn't specify where you are doing this, but since you tagged as ibm-midrange, I am answering for embedded SQL. If you want JDBC, or ODBC, or interactive SQL, the concept is similar, just the means of achieving it is different.
Make sure SQL is using dates in the correct format, it defaults to *ISO. For you it should be *EUR. In RPG, you can do it this way:
exec sql set option *datfmt = *EUR;
Make sure that set option is the first SQL statement in your program, I generally put it immediately between D and C specs.
Note that this is not an optimal solution for a program. Best practice is to set the RPG and SQL date formats both to *ISO. I like to do that explicitly. RPG date format is set by
ctl-opt DatFmt(*ISO);
SQL date format is set by
exec sql set option *datfmt = *ISO;
Now all internal dates are processed in *ISO format, and have no year range limitation (year can be 0001 - 9999). And you can display or print in any format you please. Likewise, you can receive input in any format you please.
Edit Dates are a unique beast. Not every language, nor OS knows how to handle them. If you are looking for a Date value, the only format you need to specify is the format of the string you are converting to a Date. You don't need to (can't) specify the internal format of the Date field, and the external format of a Date field can be mostly anything you want, and different each time you use it. So when you use TIMESTAMP_FORMAT() as #Stavr00 mentioned:
DATE(TIMESTAMP_FORMAT(CHAR(OAORDT),'YYYYMMDD'))
The format provided is not the format of the Date field, but the format of the data being converted to a Timestamp. Then the Date() function converts the Timestamp value into a Date value. At this point format doesn't matter because regardless of which external format you have specified by *DATFMT, the timestamp is in the internal timestamp format, and the date value is in the internal date format. The next time the format matters is when you present the Date value to a user as a string or number. At that point the format can be set to *ISO, *EUR, *USA, *JIS, *YMD, *MDY, *DMY, or *JUL, and in some cases *LONGJUL and the *Cxxx formats are available.
Since none of variants suited my needs I've came out with my own.
It is as simple as:
select * from yourschema.yourtable where yourdate = int(CURRENT DATE - 1 days) - 19000000;
This days thing is leap year-aware and suits most needs fine.
Same way days can be turned to months or years.
No need for heavy artillery like VARCHAR_FORMAT/TIMESTAMP_FORMAT.
Below worked for me:
select date(substring(trim(DateCharCol), 1, 2)||'/'||substring(trim(DateCharCol), 3, 2)||'/'||'20'||substring(trim(DateCharCol), 5, 2)) from yourTable where TableCol =?;

Sql Query using 'Like' is giving results but using '=' does not returns any result in Oracle

The Query using LIKE :(This query when fired gives the desired result)
select * from catissue_audit_event where event_timestamp like '16-DEC-14'
But when using query with '=' results in an empty resultset
select * from catissue_audit_event where event_timestamp='16-DEC-14'
Here event_timestamp is of type Date
Strange thing is that the query runs for other dates such as:
select * from catissue_audit_event where event_timestamp='15-DEC-14'
What can be the issue? I already checked for leading and trailing spaces in the data
Output after running the first query:
In Oracle a DATE (and of course a TIMESTAMP) column contains a time part as well.
Just because your SQL client is hiding the time, doesn't mean it isn't there.
If you want all rows from a specific day (ignoring the time) you need to use trunc()
select *
from catissue_audit_event
where trunc(event_timestamp) = DATE '2014-12-16';
Be aware that this query will not use an index on the event_timestamp column.
You should also not rely on implicit data type conversion as you do with the expression event_timestamp = '16-DEC-14. That statement is going to fail if I run it from my computer because of different NLS settings. Always use a proper DATE literal (as I have done in my statement). If you don't like the unambiguous ISO date, then use to_date():
where trunc(event_timestamp) = to_date('16-12-2014', 'dd-mm-yyyy');
You should avoid using month names unless you know that all environments (which includes computers and SQL clients) where your SQL statement is executed are using the same NLS settings. If you are sure, you can use e.g. to_date('16-DEC-14', 'dd-mon-yy')
The reason why this is different is different to the solution to your issue.
The solution to your issue is to stop performing date comparisons by implicit conversion to a string. Convert your string to a date to perform a date comparison:
select * from catissue_audit_event where event_timestamp = date '2014-12-16'
I cannot stress this enough; when performing a date comparison only compare dates.
Your column EVENT_TIMESTAMP is being implicitly (this is bad) converted to a date in accordance with your NLS_DATE_FORMAT, which you can find as follows:
select * from nls_session_parameters
This governs how date-data is displayed and implicitly converted. The reason why LIKE works and and = doesn't is because your NLS_DATE_FORMAT is masking additional data. In other words, your date has a time component.
If you run the following and then re-select the data from your table you'll see the additional time component
alter session set nls_date_format = 'yyyy-mm-dd hh24:mi:ss'
Thus, if you want all the data for a specific date without constraint on time you'll need to remove the time component:
select * from catissue_audit_event where trunc(event_timestamp) = date '2014-12-16'
have you tried matching the event_timestamp format example: DD-MMM-YY with the date that you are passing?

character_length Teradata SQL Assistant

I have to run column checks for data consistency and the only thing that is throwing off my code is checking for character lengths for dates between certain parameters.
SEL
sum(case when ( A.date is null or (character_length(A.date) >8)) then 1 else 0 end ) as Date
from
table A
;
The date format of the column is YYYY-MM-DD, and the type is DA. When I run the script in SQL Assistant, I get an error 3580 "Illegal use of CHARACTERS, MCHARACTERS, or OCTET_LENGTH functions."
Preliminary research suggests that SQL Assistant has issues with the character_length function, but I don't know how to adjust the code to make it run.
with chareter length are you trying to get the memory used? Becuase if so that is constant for a date field. If you are trying to get the length of the string representation i think LENGTH(A.date) will suffice. Unfortanatly since teradata will pad zeros on conversions to string, I think this might always return 10.
UPDATE :
Okay so if you want a date in a special 'form' when you output it you need to select it properly. In teradata as with most DBs Date are not store in strings, but rather as ints, counting days from a given 'epoch' date for the database (for example the epoch might be 01/01/0000). Each date type in teradata has a format parameter, which places in the record header instructions on how to format the output on select. By default a date format is set to this DATE FROMAT 'MM/DD/YYYY' I believe. You can change that by casting.
Try SELECT cast(cast(A.date as DATE FORMAT 'MM-DD-YYYY') as CHAR(10)) FROM A. and see what happens. There should be no need to validate the form of the dates past a small sample to see if the format is correct. The second cast forces the database to perform the conversion and use the format header specified. Other wise what you might see is the database will pass the date in a date form to SQL Assitant and sql assitant will perform the conversion on the application level, using the format specified in its own setting rather then the one set in the database.