I have a multilist field returning a list of values.
My query is filtering the list using IN (list), but if the user do not select anything is list, it returns an empty list, or null (I can't see).
I'm trying to do something like:
case when #list is null then 1
when c.SK_dimLocalizacao in (#list) then 1
else 0
end = 1
It works when I select none or one value, but if I select more than one it bring me an error.
I already tried to use:
case when #list = '' then 1
when c.SK_dimLocalizacao in (#list}) then 1
else 0
end = 1
I can't modify the query in backend because i'm using Pentaho.
Maybe this? (not sure if I understand the end goal)
IF LEN(ISNULL(#list,'')) <> 0
BEGIN
--Query for if the list isn't empty or null
END
ELSE
--Query for if the list is empty or null
Related
I need to verify one column only has numbers(integer number only) in oracle . If yes then set flag as 1 otherwise 0. I am trying to use below reg_exp( but it sets flag to 1 even for hyphen ):
CASE WHEN REGEXP_LIKE(Column_name,'\d\) THEN 1 ELSE 0 END
Examples:
12345 should ( this is working and above code is setting flag to 1)
-1234 should set flag to 0 ( above code is setting it to 1)
abcd should set flag to 0 ( above code is working correct in this case)
123.23 should set flag to 0
If you want check if contain only digit or not try
CASE WHEN REGEXP_LIKE(Column_name, '^[[:digit:]]+$') THEN 1 ELSE 0 END ;
You may use TRANSLATE function
SELECT case when TRANSLATE(Column_name, 'X0123456789', 'X') is null
then 1
else 0
end
FROM t;
So I have EXISTS in huge query which looks like this:
EXISTS(
SELECT
*
FROM
ExistTable
WHERE
ExTableFieldA = #SomeGuid AND
ExTableFieldB = MainTableFieldB AND
ExTableFieldA <> (
CASE
WHEN MainTableFieldZ = 10 THEN MainTableFieldYYY
ELSE NULL
END
)
)
The problem comes from ELSE part of CASE statement, this ExTableFieldA <> NULL will be always false. I could easily write another parameter #EmptyGuid and make it equal to '00000000-0000-0000-0000-000000000000' and everything will work but is this the best approach ?
Pretty much I want to execute another check into the exist for the small size of the records which return the "main" query.
How about removing the case and just using boolean logic?
WHERE ExTableFieldA = #SomeGuid AND
ExTableFieldB = MainTableFieldB AND
(MainTableFieldZ <> 10 OR ExTableFieldA <> MainTableFieldYYY)
I would also recommend that you qualify the column names by including the table alias.
Note: This does assume that MainTableFieldZ is not NULL. If that is a possibility than that logic can easily be incorporated.
ELSE NULL is implied even if you don't list it, but you could use ISNULL here.
ISNULL(ExTableFieldA,'') <> (
CASE
WHEN MainTableFieldZ = 10 THEN MainTableFieldYYY
ELSE ''
END
)
You may need to use some other value like 9999 instead of ''
I am trying to optimize a humongous SQL query that was written by a self taught developer that used a ton of functions instead of JOINS. Anyway, I am having trouble displaying a space or a empty string('') when there is no value in the field selected. I've included only the SELECT in question. I am having the weirdest problem or just overlooking the correct answer in troubleshooting. Whenever I use COALESCE, when the field is supposed to be a blank string, it displays a zero. And when I use IS NULL, I get back NULL. All info online seems to point toward using COALESCE(value, '') as depicted in the code. But I am getting a 0 instead of ''. Does anyone see what I'm doing wrong? I'm using SSMS.
SELECT
pss8.dbo.xml_StripIllegalChars(dbo.rpt_get_series_volume(b.bookkey)) AS p_seriesvol --SELECT to be replaced that works but is slow due to function use I am told
,COALESCE(bd.seriesvolume, '') AS p_seriesvol --my SELECT that won't work!
FROM
bookdetail bd
WHERE
--bd.bookkey='303177'
bd.bookkey='6002'
The bookkeys at the bottom are for testing as I know the top one returns a 1 and the bottom one returns a '' previously when it worked. The SELECT above my commented SELECT is the code that works but is slow... According to what I read online, I am saying 'if there isn't a series volume number, then it equals an empty string.' Does COALESCE not work like this? Can it only return a 0 if the field has no value, or in this case, has no volume number? All help much appreciated. I'm very curious to hear a solution!
Here's more intel. This is how the this SELECT works:
pss8.dbo.xml_StripIllegalChars(dbo.rpt_get_series_volume(b.bookkey)) AS p_seriesvol
The
.rpt_get_series_vol
function manages to create an empty string with this code... Does this reveal anything?
DECLARE #RETURN
VARCHAR(5)
DECLARE #v_desc
VARCHAR(5)
DECLARE #i_volumenumber INT
SELECT #i_volumenumber = volumenumber
FROM bookdetail
WHERE bookkey = #i_bookkey and volumenumber <> 0
IF #i_volumenumber > 0
BEGIN
SELECT #RETURN = CAST(#i_volumenumber as varchar(5))
END
ELSE
BEGIN
SELECT #RETURN = ''
END
RETURN #RETURN
END
As you are looking for a '0' not a NULL COALESCE()is not useful, instead use a simple CASE:
select
...,
case bd.seriesvolume when '0' then '' else bd.seriesvolume end as p_seriesvol
from
...
Or if you want '' for 0 or NULL
case when bd.seriesvolume is null or bd.seriesvolume = '0' then '' else bd.seriesvolume end as p_seriesvo
COALESCE() function returns the 1st non null value
SELECT COALESCE(NULL, NULL, 'third_value', 'fourth_value'); returns the third value because the third value is the first value that is not null.
So in your case COALESCE(bd.seriesvolume, '') AS p_seriesvol if seriesvolume colum value is null then it will return blank string
I am working on a select statement in SQL and am running into issues trying to create a where clause that includes a case statement or an if else statement. I want to select records based on the value of a variable. If the variable is 'True' then only return records from the select statement where a column is null. If the variable is not 'True' then return all records regardless if that columns is null.
Any tips on how to do this?
Below is a simple example of what i am trying to do:
declare #option1 as varchar(5)
--This can be True or False so to test i just put the Set option below
set #option1 = 'True'
Select a,b,c,d...
from ...
where d = case when #option1 = 'True' then NULL End
This is the part where i do not know what to do. I only need to filter out the records if the variable is 'True' so not sure what to put in the else section of the case.
You can't test for d = NULL as your CASE statement does because that will always return false since NULL is not equal to NULL (unless you set ANSI_NULLS to 'off').
The simplest thing to do would be to change the WHERE clause to this:
WHERE #option1 = 'False' OR d IS NULL
If you prefer to use a CASE statement for some reason, you can write it like this:
WHERE 1 = CASE WHEN #option1 = 'False' THEN 1
WHEN #option1 = 'True' AND d IS NULL THEN 1
ELSE 0
END
This:
UPDATE: PinnyM has straightened me out on this. I am leaving my embarrassing logically flawed argument here for the education of the masses. The solution I propose below after "Try this" is certainly still valid, but PinnyM's solutions is by far more elegant and should be used.
WHERE #option1 = 'False' OR d IS NULL
Will always return all the results given his current select statement (assuming #Option1 is simply a flag parameter passed in).
Try this:
SELECT a, b, c, d
WHERE
-- Returns only rows where d is null (if #Option1 is True)
(#Option1 = 'True' AND d IS NULL)
OR
-- returns all the rows (if #Option1 is False)
(#Option1 = 'False')
A SQL Table (Trades) has three fields AvgProfit, MinProfit and Hold - Hold is a Computed Colum...
If AvgProfit < MinProfit, Hold = 'Hold' and if AvgProfit > MinProfit, Hold = 'Trade'
The Computed Col formula for Hold is as follows.
SQL Table Trades
AvgProfit varchar(35)
MinProfit varchar(35)
Hold varchar(35)
(case when CONVERT([decimal](8,4),isnull([AvgProfit],(0)),(0))>=CONVERT([decimal](8,4),isnull([MinProfit],(0)),(0)) then 'Trade' else 'Hold' end)
PROBLEM: Updates cause the AvgProfit to be empty at times and this results in an error when the table references the Hold formula
'Error Converting varchar to numeric'
How do I add IS NULL or EMPTY to the above formula, the ISNULL does not catch AvgProfit = '' ??
Consider typing your database with decimal or numeric columns as paxdiablo has suggested. Is there a reason why those columns are set as varchar?
Alternatively if you have to keep your varchar columns, try ISNUMERIC(), http://msdn.microsoft.com/en-us/library/ms186272.aspx. It works with all common SQL numeric types. So you query might become:
ISNUMERIC can be used like this:
select case when ISNUMERIC('123') = 1 then 1 else 0 end ' returns 1
select case when ISNUMERIC('xyz') = 1 then 1 else 0 end ' returns 0
select case when ISNUMERIC(null) = 1 then 1 else 0 end ' returns 0
So your query might become:
case when isnumeric(AvgProfit) = 1 THEN case([AvgProfit] as decimal) else 0 END
Or something similar.
varchar columns should be used for VARiable sized CHARacter columns, not for numeric data.
In other words, they shouldn't be empty (other than NULL, of course, but you've taken care of that).
If you cannot fix that little oversight for some reason, you can make your queries even more complex and slower :-) by doing something like:
select case when xyz = '' then 0 when isnull(xyz) then 0 else xyz end ...
In other words, check for both NULL and empty varchar values.
Myself,I'd fix the schema since it'll be better for you in the long term. I'm merely offering the other solution on the chance that you're not able to do that.