SQL query not retrieving data - sql

SELECT DISTINCT
TO_CHAR(CREATION_DATE,'MONTH') creation_month
FROM
AP_INVOICES_ALL;
This query retrieves the month properly. But if I pass the month in where clause it doesn't retrieve data.
SELECT DISTCINT
TO_CHAR(CREATION_DATE, 'MONTH') CREATION_MONTH
FROM
AP_INVOICES_ALL
WHERE
TO_CHAR(CREATION_DATE, 'MONTH') = 'MARCH';
Please assist. I need to pass month as parameter in one report.

This is a known issue with 'MONTH' formats. The string is padded with characters.
Instead, use 'MON'. Check this out:
select to_char(sysdate, 'MONTH'),
(case when to_char(sysdate, 'MONTH')= 'APRIL' then 1 else 0 end),
to_char(sysdate, 'MON'),
(case when to_char(sysdate, 'MON')= 'APR' then 1 else 0 end)
from dual;
The first case expression returns 0 -- no match. The second returns 1, indicating that they do match.

I think passing in just the month, without the year, is not a good idea. And you will be far better off treating dates as dates, comparing them to dates, etc. Might I suggest something like the following?
SELECT TO_CHAR(creation_date, 'MONTH') AS creation_month
FROM ap_invoices_all
WHERE TRUNC(creation_date, 'MONTH') = DATE'2018-03-01';
TRUNC()ing the date to the month will return a value of type DATE of the first of the month at midnight. You can then compare using regular Oracle DATE values or ANSI DATE literals as above.
Hope this helps.

Related

Case When in SQL , Two Different Attributes

New to the forum. I am looking to use a CASE WHEN function based on two separate fields . Those fields are order day and Month . Month is a calculation from:
DATEPART (Month, order_day ) AS Month
The code I have is below, but not getting the desired result. Want to say when order day is between x dates, then have the data in the Month column 1, otherwise give me the normal data that appears in the Month column.
when order_day between to_date ('20201227', 'YYYYMMDD') and TO_DATE ('20201231', 'YYYYMMDD') THEN Month = '1'
else Month End As Month2
Not easy to understand the question, but your case when in a SELECT statement should look like this:
SELECT
case when order_day between to_date ('20201227', 'YYYYMMDD') and TO_DATE('20201231', 'YYYYMMDD')
then Month = '1'
else Month
end

Oracle : Selecting date by month with where clause

I came across a problem that in selecting the date for current desired month and year. I tried the 2 statements shown below but failed to execute the query
select to_char(sysdate, 'Month') from income
select * from income where to_char(sysdate,month) = 'feb'
Update
But after researching and learning more in depth on oracle docs website. What i came out with is to use "between" clause. Specifying the first day and last day of the month . Doing so, it will execute the desired month/year
For an example
SELECT column_name
FROM table_name where column_name = (Your own value) AND
column_date >= to_date('01/02/2012', 'dd/mm/yyyy')
and column_date < to_date('01/03/2012', 'dd/mm/yyyy')
I hope this help :)
Are you after something like:
select *
from income
where <date_column> >= to_date('01/05/2019', 'dd/mm/yyyy')
and <date_column> < to_date('01/06/2019', 'dd/mm/yyyy')
(replacing <date_column> with the name of the date column in your income table that you want to filter on)?
I think you can use the following query:
select *
from income
where to_char(<date_column>,'MON-RRRR') = 'MAY-2019';
If you want to pass in a string like 'May 2012', then I would recommend:
select i.*
from income i
where i.datecol >= to_date('May 2012', 'Mon YYYY') and
i.datecol < to_date('May 2012', 'Mon YYYY') + interval '1' month;
That said, I think your application should turn the string value into a date range and you should use that range in your query:
select i.*
from income i
where i.datecol >= :datestart
i.datecol < :dateend + interval '1 day';
I strong encourage you to avoid between with dates, particularly in Oracle. The date data type has a built-in time component, and that can throw off the comparisons.

How to format a Vertica date column into just the month?

I am trying to format a Vertica date column into only the month.
I would need the final value in some sort of date datatype so in the report I can order the results by date/time, not order by text. So that February sorts after January etc.
select TO_DATE(TO_CHAR(purchase_date), 'Month')
from transactions
order by 1;
I am also tried:
select TO_DATE(TO_CHAR(MONTH(purchase_date)), 'Month')
from transactions
order by 1;
The above statements produce an error "Invalid value for Month"
Any ideas?
How about this?
select to_char(purchase_date, 'Month')
from transactions
order by purchase_date;
You can order by columns that are not in the select list.
EDIT:
If you want to combine months from multiple years, the above will not work quite right. This will:
select to_char(purchase_date, 'Month')
from transactions
order by extract(month from purchase_date);
Select TO_CHAR((NOW() - INTERVALYM '1 MONTH'), 'MON');
Output:
JUN
This will help you get only the name of the previous month.
We can directly use date_part to get a month from the timestamp.
SELECT DATE_PART('MONTH', purchase_date) purchase_date
TO_DATE gives the complete date, if you only provide MM in the parameter then Vertica set default year and day.
Let suppose the month number is 8.
SELECT TO_DATE(purchase_date, 'MM')
Output: (0001-08-01)

Oracle SQl Dev, how to calc num of weekdays between 2 dates

Does anyone know how can I calculate the number of weekdays between two date fields? I'm using oracle sql developer. I need to find the average of weekdays between multiple start and end dates. So I need to get the count of days for each record so I can average them out. Is this something that can be done as one line in the SELECT part of my query?
This answer is similar to Nicholas's, which isn't a surprise because you need a subquery with a CONNECT BY to spin out a list of dates. The dates can then be counted while checking for the day of the week. The difference here is that it shows how to get the weekday count value on each line of the results:
SELECT
FromDate,
ThruDate,
(SELECT COUNT(*)
FROM DUAL
WHERE TO_CHAR(FromDate + LEVEL - 1, 'DY') NOT IN ('SAT', 'SUN')
CONNECT BY LEVEL <= ThruDate - FromDate + 1
) AS Weekday_Count
FROM myTable
The count is inclusive, meaning it includes FromDate and ThruDate. This query assumes that your dates don't have a time component; if they do you'll need to TRUNC the date columns in the subquery.
You could do it the following way :
Lets say we want to know how many weekdays between start_date='01.08.2013' and end_date='04.08.2013' In this example start_date and end_date are string literals. If your start_date and end_date are of date datatype, the TO_DATE() function won't be needed:
select count(*) as num_of_weekdays
from ( select level as dnum
from dual
connect by (to_date(end_date, 'dd.mm.yyyy') -
to_date(start_date, 'dd.mm.yyyy') + 1) - level >= 0) s
where to_char(sysdate + dnum, 'DY',
'NLS_DATE_LANGUAGE=AMERICAN') not in ('SUN', 'SAT')
Result:
num_of_weekdays
--------------
2
Checkout my complete working function code and explanation at
https://sqljana.wordpress.com/2017/03/16/oracle-calculating-business-days-between-two-dates-in-oracle/
Once you have created the function just use the function as part of the SELECT statement and pass in the two date columns for Start and End dates like this:
SELECT Begin_Date, End_Date, fn_GetBusinessDaysInterval(Begin_Date, End_Date) AS BusinessDays FROM YOURTABLE;

Oracle date function for the previous month

I have the query below where the date is hard-coded. My objective is to remove the harcoded date; the query should pull the data for the previous month when it runs.
select count(distinct switch_id)
from xx_new.xx_cti_call_details#appsread.prd.com
where dealer_name = 'XXXX'
and TRUNC(CREATION_DATE) BETWEEN '01-AUG-2012' AND '31-AUG-2012'
Should I use sysdate-15 function for that?
Modifying Ben's query little bit,
select count(distinct switch_id)
from xx_new.xx_cti_call_details#appsread.prd.com
where dealer_name = 'XXXX'
and creation_date between add_months(trunc(sysdate,'mm'),-1) and last_day(add_months(trunc(sysdate,'mm'),-1))
The trunc() function truncates a date to the specified time period; so trunc(sysdate,'mm') would return the beginning of the current month. You can then use the add_months() function to get the beginning of the previous month, something like this:
select count(distinct switch_id)
from xx_new.xx_cti_call_details#appsread.prd.com
where dealer_name = 'XXXX'
and creation_date >= add_months(trunc(sysdate,'mm'),-1)
and creation_date < trunc(sysdate, 'mm')
As a little side not you're not explicitly converting to a date in your original query. Always do this, either using a date literal, e.g. DATE 2012-08-31, or the to_date() function, for example to_date('2012-08-31','YYYY-MM-DD'). If you don't then you are bound to get this wrong at some point.
You would not use sysdate - 15 as this would provide the date 15 days before the current date, which does not seem to be what you are after. It would also include a time component as you are not using trunc().
Just as a little demonstration of what trunc(<date>,'mm') does:
select sysdate
, case when trunc(sysdate,'mm') > to_date('20120901 00:00:00','yyyymmdd hh24:mi:ss')
then 1 end as gt
, case when trunc(sysdate,'mm') < to_date('20120901 00:00:00','yyyymmdd hh24:mi:ss')
then 1 end as lt
, case when trunc(sysdate,'mm') = to_date('20120901 00:00:00','yyyymmdd hh24:mi:ss')
then 1 end as eq
from dual
;
SYSDATE GT LT EQ
----------------- ---------- ---------- ----------
20120911 19:58:51 1
Data for last month-
select count(distinct switch_id)
from xx_new.xx_cti_call_details#appsread.prd.com
where dealer_name = 'XXXX'
and to_char(CREATION_DATE,'MMYYYY') = to_char(add_months(trunc(sysdate),-1),'MMYYYY');
I believe this would also work:
select count(distinct switch_id)
from xx_new.xx_cti_call_details#appsread.prd.com
where
dealer_name = 'XXXX'
and (creation_date BETWEEN add_months(trunc(sysdate,'mm'),-1) and trunc(sysdate, 'mm'))
It has the advantage of using BETWEEN which is the way the OP used his date selection criteria.
It is working with me in Oracle sql developer
SELECT add_months(trunc(sysdate,'mm'), -1),
last_day(add_months(trunc(sysdate,'mm'), -1))
FROM dual
Getting last nth months data retrieve
SELECT * FROM TABLE_NAME
WHERE DATE_COLUMN BETWEEN '&STARTDATE' AND '&ENDDATE';