Hi so I have a question regarding case statements and why certain statements dont work.
(Case WHEN LENGTH(input)<=5 THEN text LIKE '%'
ELSE text = input)
When I did this, it didnt work and im still confused as to why.
However the solution to this problem was
(Case WHEN LENGTH(input)<=5 THEN text LIKE Concat('%',input,'%')
ELSE text = input END)
However My main question is below though I would like an answer to the above question and since they are identical I will leave it as one question.
I have a student who is still being reviewed for entering the school, however this school is german so i need to translate a few words for them since the system is in English
select s.fname, s.lastname,
(Case when s.status like 'APPROVED' then s.status = 'Genehmigt'
when s.status like 'PENDING' then s.status = 'Anstehend.'
end) as Status
from Student
My results are giving me False in the status field so obviously im doing something wrong...
And I know there are two types of case statement so am I using the recommended one?
The expression you have placed after then:
s.status = 'Genehmigt'
is not an assignment, it is a boolean expression, so it yields true or false.
s.status = is just redundant.
select
fname,
lastname,
case when status = 'APPROVED' then 'Genehmigt'
when status = 'PENDING' then 'Anstehend.'
end as status
from student
Note that like with a string without wildcards on the right side should be a simple comparison.
Related
I have a query in postgresql where I want to append a minus sign to the transactions.amount field when the transaction.type = 2 (which refers to withdrawals). I am trying to concat a minus sign and the transactions.amount field which is an int. I casted the transactions.amount field to a text/varchar but no matter what I still get the error, "PostgreSql Error: case types numeric and text cannot be matched"
Here is the query I am running,
SELECT CAST(CASE WHEN "IsVoided" IS TRUE THEN 0
WHEN "Transactions"."TransactionType" = 2
THEN CONCAT('-', CAST("Transactions"."Amount" AS TEXT))
ELSE "Transactions"."Amount" END AS Text) AS "TransAmount"
FROM "Transactions"
LEFT JOIN "DepositSources"
ON "Transactions"."DepositSourceId" =
"DepositSources"."DepositSourceId"
LEFT JOIN "WithdrawalSources"
ON "Transactions"."WithdrawalSourceId" =
"DepositSources"."DepositSourceId"
WHERE "Transactions"."FundId" = 4
AND "Transactions"."ReconciliationId" = 24
What's very perplexing is when i run the below query it works as expected,
SELECT CONCAT('-', CAST("Transactions"."Amount" AS TEXT)) FROM
"Transactions"
All branches of a CASE expression need to have the same type. In this case, you're stuck with making all branches text, because what follows THEN can only be text. Try this version:
CASE WHEN IsVoided IS TRUE
THEN '0'
WHEN Transactions.TransactionType = 2
THEN CONCAT('-', Transactions.Amount::text)
ELSE Transactions.Amount::text END AS TransAmount
Note that it is unusual to be using the logic you have in a CASE expression. Typically, you would just be checking the values of a single column, not multiple different columns.
Edit:
It appears that your call to CONCAT mainly serves to negative a value. Here is one more simple way to do this:
CASE WHEN IsVoided IS TRUE
THEN 0
WHEN Transactions.TransactionType = 2
THEN -1.0 * Transactions.Amount
ELSE Transactions.Amount END AS TransAmount
In this case, we can make the CASE expression just generate numeric output, which might be really what you are after.
In DB2 SQL, is it possible to SET a variable with the contents of a returned field in the SELECT statement, to use multiple times for calculated fields and criteria further along in the same SELECT statement?
The purpose is to shrink and streamline the code, by doing a calculation once at the beginning and using it multiple times later on...including the HAVING, WHERE, and ORDER BY.
To be honest, I'm not sure this is possible in any version of SQL, much less DB2.
This is on an IBM iSeries 8202 with DB2 SQL v6, which unfortunately is not a candidate for upgrade at this time. This is a very old & messy database, which I have no control over. I must regularly include "cleanup functions" in my SQL.
To to clarify the question, note the following pseudocode. Actual working code follows further below.
DECLARE smnum INTEGER --Not sure if this is correct.
SELECT
-- This is where I'm not sure what to do.
SET CAST((CASE WHEN %smnum%='' THEN '0' ELSE %smnum% END) AS INTEGER) INTO smnum,
%smnum% AS sm,
invdat,
invno,
daqty,
dapric,
dacost,
(dapric-dacost)*daqty AS profit
FROM
saleshistory
WHERE
%smNum% = 30
ORDER BY
%smnum%
Below is my actual working SQL. When adjusted for 2017 or 2016, it can return >10K rows, depending on the salesperson. The complete table has >22M rows.
That buttload of CASE((CAST... function is what I wish to replace with a variable. This is not the only example of this. If I can make it work, I have many other queries that could benefit from the technique.
SELECT
CAST((CASE WHEN TRIM(DASM#)='' THEN '0' ELSE TRIM(DASM#) END) AS INTEGER) AS DASM,
DAIDAT,
DAINV# AS DAINV,
DALIN# AS DALIN,
CAST(TRIM(DAITEM) AS INTEGER) AS DAITEM,
TRIM(DABSW) AS DABSW,
TRIM(DAPCLS) AS DAPCLS,
DAQTY,
DAPRIC,
DAICOS,
DADPAL,
(DAPRIC-DAICOS+DADPAL)*DAQTY AS PROFIT
FROM
VIPDTAB.DAILYV
WHERE
CAST((CASE WHEN TRIM(DASM#)='' THEN '0' ELSE TRIM(DASM#) END) AS INTEGER)=30 AND
TRIM(DABSW)='B' AND
DAIDAT BETWEEN (YEAR(CURDATE())*10000) AND (((YEAR(CURDATE())+1)*10000)-1) AND
CAST(TRIM(DACOMP) AS INTEGER)=1
ORDER BY
CAST((CASE WHEN TRIM(DASM#)='' THEN '0' ELSE TRIM(DASM#) END) AS INTEGER),
DAIDAT,
DAINV#,
DALIN#
Just use a subquery or CTE. I can't figure out the actual logic you want, but the structure looks like this:
select . . .
from (select d.*,
(CASE . . . END) as calc_field
from VIPDTAB.DAILYV d
) d
No variable declaration is needed.
Here is what your SQL would look like with the sub-query that Gordon suggested:
SELECT
DASM,
DAIDAT,
DAINV# AS DAINV,
DALIN# AS DALIN,
CAST(DAITEM AS INTEGER) AS DAITEM,
TRIM(DABSW) AS DABSW,
TRIM(DAPCLS) AS DAPCLS,
DAQTY,
DAPRIC,
DAICOS,
DADPAL,
(DAPRIC-DAICOS+DADPAL)*DAQTY AS PROFIT
FROM
(SELECT
D.*,
CAST((CASE WHEN D.DASM#='' THEN '0' ELSE D.DASM# END) AS INTEGER) AS DASM
FROM VIPDTAB.DAILYV D
) D
WHERE
DASM=30 AND
TRIM(DABSW)='B' AND
DAIDAT BETWEEN (YEAR(CURDATE())*10000) AND (((YEAR(CURDATE())+1)*10000)-1) AND
CAST(DACOMP AS INTEGER)=1
ORDER BY
DASM,
DAIDAT,
DAINV#,
DALIN#
Notice that I removed a lot of the trim() functions, and you could likely remove the rest. The way IBM resolves the Varchar vs. Char comparison thing is by ignoring trailing blanks. So trim(anything) = '' is the same as anything = ''. And since cast(' 123 ' as integer) = 123, I have removed trims from within the cast functions as well. In addition trim(dabsw) = 'B' is the same as dabsw = 'B' as long as the 'B' is the first character in dabsw. So you could even remove that trim if all you are concerned with is trailing blanks.
Here are some additional notes based on comments. The above paragraph is not talking about auto-trim. Fixed length fields will always return as fixed length fields, the trailing blanks will remain. But in comparisons and expressions where trailing blanks are unimportant, or even a hindrance, they are ignored. In expressions where trailing blanks are important, like concatenation, the trailing blanks are not ignored. Another thing, trim() removes both leading and trailing blanks. If you are using trim() to read a fixed length character field into a Varchar, then rtrim() is likely the better choice as it only removes the trailing blanks.
Also, I didn't go through your fields to make sure I got everything you need, I just used * in the sub-query. For performance, it would be best to only return the fields you need. So if you replace D.* with an actual field list, you can remove the correlation name in the from clause of the sub-query. But, the sub-query itself still needs a correlation clause.
My verification was done using IBM i v7.1.
You can encapsalate the case statement in a view. I even have the fancy profit calc in there for you to order by profit. Now the biggest issue you have is the CCSID on the view for calculated columns but that's another question.
create or replace view VIPDTAB.DAILYVQ as
SELECT
CAST((CASE WHEN TRIM(DASM#)='' THEN '0' ELSE TRIM(DASM#) END) AS INTEGER) AS DASM,
DAIDAT,
DAINV# AS DAINV,
DALIN# AS DALIN,
CAST(TRIM(DAITEM) AS INTEGER) AS DAITEM,
TRIM(DABSW) AS DABSW,
TRIM(DAPCLS) AS DAPCLS,
DAQTY,
DAPRIC,
DAICOS,
DADPAL,
(DAPRIC-DAICOS+DADPAL)*DAQTY AS PROFIT
FROM
VIPDTAB.DAILYV
now you can
select dasm, count(*) from vipdtab.dailyvq where dasm = 0 group by dasm order by dasm
or
select * from vipdtab.dailyvq order by profit desc
I wrote this snippet of code here in Oracle SQL Developer but I don't know how to use a CASE WHEN so that when k.QUARANTINED = 0, display 'No', else if k.QUARANTINED = 1 display 'Yes'. This column is always 0 or 1.
select
s.NAME as "Shipment ID"
,k.STATUS_ID as "Status"
,k.EXPIRATION
,k.DISDATE
,u.SCR_NO as "Patient No"
,k.QUARANTINED
,k.PREVIOUS_STATUS_ID
,k.SORT_KEY as "Sort Order"
from KIT k
left join SHIPMENT s on s.ID = k.SHIPMENT_ID
left join USR u on u.PAT_ID = k.PAT_ID;
I tried a couple of times but kept getting errors most likely since I don't know how write the syntax correctly or maybe I have to rewrite this completely differently? I'd like to keep the order of the columns the same. I just would like to see 'Yes' or 'No' for k.Quarantined instead of 0 or 1 returned in the result. :)
SELECT
S.name AS "shipment ID",
K.status_id AS "status",
K.expiration,
K.disdate,
U.scr_no AS "Patient No",
K.quarantined,
CASE k.quarantined
WHEN 0 THEN 'No'
WHEN 1 THEN 'Yes'
ELSE 'Missing or Null'
END AS "quarantine status case example 1",
CASE
WHEN k.quarantined = 0
THEN 'No'
WHEN k.quarantined = 1
THEN 'Yes'
ELSE 'Missing or Null'
END AS "quarantine status case example 2",
K.previous_status_id,
K.sort_key AS "sort order",
FROM Kit K
LEFT JOIN Shipment S
ON K.shipment_id = S.id
LEFT JOIN USR U
ON K.pat_id = U.pat_id
ORDER BY
K.sort_key ASC
;
Two examples of CASE above. The first example is used when you are evaluating a single column/variable.
The second example is used for testing multiple conditions.
When using the second example of CASE statements, it is important to understand that CASE will return the result for the first condition that evaluates TRUE. When using complex logic, sometimes a developer may (inadvertently) have overlapping logic where multiple conditions can be satisfied. When unexpected results from CASE occur, it is important to go back and reevaluate the statement from the top down.
If you are absolutely sure that K.quarantined cannot be NULL and it can only be 0 or one (research the table DDL for check constraints) then you can remove or comment out the ELSE clause on the CASE statements--but it is generally good practice to always have an ELSE clause for consistency. You can have it simply state "ELSE NULL" if you do not ever expect anything other than what's described in your CASE statement.
Lastly, be sure to make sure to identify whether K.quarantined is numeric or text (check table DDL). If it is actually storing text '0' or '1', then should change your literals accordingly--although I think current versions of Oracle are smart enough to do the implicit conversions for you.
Probably something really trivial but I haven't quite found the answer I am looking for on the internet and I get syntax errors with this. What I want/need to do is to provide a special case in my where clause where the doctype is 1. If it is, then it needs to match the claimID from a sub select of a temp table. If the doctype is not a 1 then we just need to continue on and ignore the select.
AND
CASE
WHEN #DocType = 1 THEN (c.ClaimID IN (SELECT TNE.ClaimID FROM TNE)
END
I have seen some for if statements but I didn't seem to get that to work and haven't found anything online as of yet that shows a case statement doing what I would like. Is this even possible?
You don't need a case statement, you could do:
AND (#DocType <> 1 or c.ClaimID in (SELECT TNE.ClaimID FROM TNE))
A CASE expression (not statement) returns a single value. SQL Server supports the bit data type. (Valid values are 0, 1, 'TRUE' and 'FALSE'.) There is a boolean data type (with values TRUE, FALSE and UNKNOWN), but you cannot get a firm grip on one. Your CASE expression attempts to return a boolean, give or take the unmatched parenthesis, which is not supported in this context.
You could use something like this, though Luc's answer is more applicable to the stated problem:
and
case
when #DocType = 1 and c.ClaimId in ( select TNE.ClaimId from TNE ) then 1
when #DocType = 2 and ... then 1
...
else 0
end = 1
Note that the CASE returns a value which you must then compare (= 1).
I need to further refine my stored proc resultset from this post, I need to filter my resultset to display only records where emailaddr is NULL (meaning display only records that have Invoice_DeliveryType value of 'N' ).
Among numerous queries, I have tried:
select
Invoice_ID, 'Unknown' as Invoice_Status,
case when Invoice_Printed is null then '' else 'Y' end as Invoice_Printed,
case when Invoice_DeliveryDate is null then '' else 'Y' end as Invoice_Delivered,
(case when Invoice_DeliveryType <> 'USPS' then ''
when exists (Select 1
from dbo.Client c
Where c.Client_ID = SUBSTRING(i.Invoice_ID, 1, 6) and
c.emailaddr is not null
)
then 'Y'
else 'N'
end)
Invoice_ContactLName + ', ' + Invoice_ContactFName as ContactName,
from
dbo.Invoice
left outer join
dbo.fnInvoiceCurrentStatus() on Invoice_ID = CUST_InvoiceID
where
CUST_StatusID = 7
AND Invoice_ID = dbo.Client.Client_ID
AND dbo.client.emailaddr is NULL
order by
Inv_Created
but I get an error
The conversion of the nvarchar value '20111028995999' overflowed an int column
How can I get the stored procedure to only return records with DeliveryType = 'N' ?
Trying selecting the stored proc results into a temp table, then select
* from #TempTable
We could really do with a schema definition to get this problem resolved.
It appears that there is an implicit conversion occurring within one of your case statements, but without the schema def's it's difficult to track down which one.
You can't safely mix datatypes in CASE expressions, unless you are absolutely sure that any implicit conversions will work out OK you should make the conversions explicit.
Judging by the error message seeming to include something that could be a date represented as a string(20111028) plus some kind of other data ?time?(995999) it may be something to do with Invoice_DeliveryDate, but this is a shot in the dark without more details.