I don't know if this is possible, but this is the question. I try to change operator = by > if paramvalue = 0
AS $BODY$
declare
operator text;
begin
operator:='=';
if (paramvalue = 0) then
operator:='>';
end if;
select * from tablaname where id #operator 20
thanks!
I think overloading an operator is more complex than what you need for this behavior. You could try using a CASE statement instead.
SELECT *
FROM tablename
WHERE CASE WHEN paramvalue = 0
THEN id > 20
ELSE id = paramvalue
END
;
If you really want to overload an operator I suggest taking a look at the postgres documentation here.
REMARK NOT TESTED !!
In your scenario solution could be...:
.....
if (paramvalue = 0) then
select * from tablaname where id > 20
Else
select * from tablaname where id = 20
end if;
Please read this 9.16. Conditional Expressions
And this would be rather:
CASE WHEN paramvalue = 0 THEN select * from tablaname where id > 20
ELSE select * from tablaname where id = 20
END
Hey I have this query
IF (select kmkood from or_arved_read where kmkood = '1' or kmkood = '14' or kmkood = '15' or kmkood = '6' )
BEGIN
SET #stat_vat = 21
IF (select kmkood from or_arved_read where kmkood = '2' or kmkood = '7' )
SET #stat_vat = 12
But it returns An expression of non-boolean type specified in a context where a condition is expected, near 'BEGIN'.
how can i fix it?
Firstly, your IF doesn't have a boolean expression. The subquery returns a value (or more accurately for this scenario will return many and cause a different error) for the column kmkood, but then you don't do anything with that value. What value does that column need? The format should be something like this:
IF (SELECT SomeColumn FROM dbo.SomeTable WHERE... ) = 'SomeValue'
Also, if you have a BEGIN you need an END afterwards, which you don't have:
IF (SELECT SomeColumn FROM dbo.SomeTable WHERE... ) = 'SomeValue'
BEGIN
{Do several statements}
END
As, however, you are just doing a SET statement then you don't actually need the BEGIN and END statements.
I suspect what you are really after here, however, in an EXISTS:
IF EXISTS(SELECT 1 FROM dbo.or_arved_read WHERE kmkood IN (1,14,15,6))
SET #stat_vat = 21;
IF EXISTS(SELECT 1 FROM dbo.or_arved_read WHERE kmkood IN (2,7))
SET #stat_vat = 12;
You don't need all those ORs either, an IN works fine, and numbers shouldn't be in single quotes, so that makes things a bit shorter.
I have a table. I have 2 variables, one is a bit, the other is an int.
Table: WorkGroupCollectionDetail
Variables: #WorkgroupID int, #IsFSBP bit
The table has WorkGroupId int PK and WorkGroupCollectionCode varchar PK. That's it.
I can run a query like this:
SELECT WorkGroupId
FROM WorkGroupCollectionDetail
WHERE WorkGroupCollectionCode = 'FSBP'
and it gives me a list of WorkGroupID.
So what I need to do is if the value of #WorkgroupID is inside the results of that query, I need to set the bit variable to true.
select #IsFBSP = case
when exists (
select 42 from WorkGroupDetailCollection
where WorkGroupCollectionCode = 'FSBP' and WorkGroupId = #WorkGroupId ) then 1
else 0 end
which is logically equivalent to:
select #IsFBSP = case
when #WorkGroupId in (
select WorkGroupId from WorkGroupDetailCollection
where WorkGroupCollectionCode = 'FSBP' ) then 1
else 0 end
A query using EXISTS often performs better than a query using IN. You can check the execution plans to see how they compare in your particular case.
Note that these examples include setting the bit value to zero as well as one.
You could modify the SELECT to include the check for the WorkGroupId and update the #IsFSBP accordingly:
IF EXISTS(SELECT WorkGroupId
FROM WorkGroupCollectionDetail
WHERE WorkGroupCollectionCode = 'FSBP'
AND WorkGroupId = #WorkgroupID)
BEGIN
SELECT #IsFSBP = 1;
END
SQL Fiddle example
I'm guessing you're looking for
Set #BitVariable = count(*)
From TestTable
WHERE TestCode = 'TestValue' and TestID = #TestID
I have a huge query which uses case/when often. Now I have this SQL here, which does not work.
(select case when xyz.something = 1
then
'SOMETEXT'
else
(select case when xyz.somethingelse = 1)
then
'SOMEOTHERTEXT'
end)
(select case when xyz.somethingelseagain = 2)
then
'SOMEOTHERTEXTGOESHERE'
end)
end) [ColumnName],
Whats causing trouble is xyz.somethingelseagain = 2, it says it could not bind that expression. xyz is some alias for a table which is joined further down in the query. Whats wrong here? Removing one of the 2 case/whens corrects that, but I need both of them, probably even more cases.
SELECT
CASE
WHEN xyz.something = 1 THEN 'SOMETEXT'
WHEN xyz.somethingelse = 1 THEN 'SOMEOTHERTEXT'
WHEN xyz.somethingelseagain = 2 THEN 'SOMEOTHERTEXTGOESHERE'
ELSE 'SOMETHING UNKNOWN'
END AS ColumnName;
As soon as a WHEN statement is true the break is implicit.
You will have to concider which WHEN Expression is the most likely to happen. If you put that WHEN at the end of a long list of WHEN statements, your sql is likely to be slower. So put it up front as the first.
More information here: break in case statement in T-SQL
declare #n int = 7,
#m int = 3;
select
case
when #n = 1 then
'SOMETEXT'
else
case
when #m = 1 then
'SOMEOTHERTEXT'
when #m = 2 then
'SOMEOTHERTEXTGOESHERE'
end
end as col1
-- n=1 => returns SOMETEXT regardless of #m
-- n=2 and m=1 => returns SOMEOTHERTEXT
-- n=2 and m=2 => returns SOMEOTHERTEXTGOESHERE
-- n=2 and m>2 => returns null (no else defined for inner case)
If logical test is against a single column then you could use something like
USE AdventureWorks2012;
GO
SELECT ProductNumber, Category =
CASE ProductLine
WHEN 'R' THEN 'Road'
WHEN 'M' THEN 'Mountain'
WHEN 'T' THEN 'Touring'
WHEN 'S' THEN 'Other sale items'
ELSE 'Not for sale'
END,
Name
FROM Production.Product
ORDER BY ProductNumber;
GO
More information - https://learn.microsoft.com/en-us/sql/t-sql/language-elements/case-transact-sql?view=sql-server-2017
OK, the umpteenth conditional column question:
I'm writing a stored proc that takes an input parameter that's mapped to one of several flag columns. What's the best way to filter on the requested column? I'm currently on SQL2000, but about to move to SQL2008, so I'll take a contemporary solution if one's available.
The table queried in the sproc looks like
ID ... fooFlag barFlag bazFlag quuxFlag
-- ------- ------- ------- --------
01 1 0 0 1
02 0 1 0 0
03 0 0 1 1
04 1 0 0 0
and I want to do something like
select ID, name, description, ...
from myTable
where (colname like #flag + 'Flag') = 1
so if I call the sproc like exec uspMyProc #flag = 'foo' I'd get back rows 1 and 4.
I know I can't do the part in parens directly in SQL. In order to do dynamic SQL, I'll have to stuff the entire query into a string, concatenate the #flag param in the WHERE clause and then exec the string. Aside from the dirty feeling I get when doing dynamic SQL, my query is fairly large (I'm selecting a couple dozen fields, joining 5 tables, calling a couple of functions), so it's a big giant string all because of a single line in a 3-line WHERE filter.
Alternately, I could have 4 copies of the query and select among them in a CASE statement. This leaves the SQL code directly executable (and subject to syntax hilighting, etc.) but at the cost of repeating big chunks of code, since I can't use the CASE on just the WHERE clause.
Are there any other options? Any tricky joins or logical operations that can be applied? Or should I just get over it and exec the dynamic SQL?
There are a few ways to do this:
You can do this with a case statement.
select ID, name, description, ...
from myTable
where CASE
WHEN #flag = 'foo' then fooFlag
WHEN #flag = 'bar' then barFlag
END = 1
You can use IF.
IF (#flag = 'foo') BEGIN
select ID, name, description, ...
from myTable
where fooFlag = 1
END ELSE IF (#flag = 'bar') BEGIN
select ID, name, description, ...
from myTable
where barFlag = 1
END
....
You can have a complicated where clause with a lot of parentheses.
select ID, name, description, ...
from myTable
where (#flag = 'foo' and fooFlag = 1)
OR (#flag = 'bar' and barFlag = 1) OR ...
You can do this with dynamic sql:
DECLARE #SQL nvarchar(4000)
SELECT #SQL = N'select ID, name, description, ...
from myTable
where (colname like ''' + #flag + 'Flag'') = 1'
EXECUTE sp_ExecuteSQL #SQL, N''
There are more, but I think one of these will get you going.
"Alternately, I could have 4 copies of the query and select among them in a CASE statement."
You don't need to copy your entire query 4 times, just add all the possibilities into the where clauses in your single copy of the query:
select ID, name, description, ...
from myTable
where (#flag = 'foo' and fooFlag = 1) OR (#flag = 'bar' and barFlag = 1) OR ...
What I would do is CASE some variables at the beginning. Example:
DECLARE
#fooFlag int,
#barFlag int,
#bazFlag int,
#quuxFlag int
SET #fooFlag = CASE WHEN #flag = 'foo' THEN 1 ELSE NULL END
SET #barFlag = CASE WHEN #flag = 'bar' THEN 1 ELSE NULL END
SET #bazFlag = CASE WHEN #flag = 'baz' THEN 1 ELSE NULL END
SET #quuxFlag = CASE WHEN #flag = 'quux' THEN 1 ELSE NULL END
SELECT ID, name, description, ...
FROM myTable
WHERE (fooFlag >= ISNULL(#fooFlag, 0) AND fooFlag <= ISNULL(#fooFlag, 1))
AND (barFlag >= ISNULL(#barFlag, 0) AND barFlag <= ISNULL(#barFlag, 1))
AND (bazFlag >= ISNULL(#bazFlag, 0) AND bazFlag <= ISNULL(#bazFlag, 1))
AND (quuxFlag >= ISNULL(#quuxFlag, 0) AND quuxFlag <= ISNULL(#quuxFlag, 1))
The good thing about this query is that, because the possible values for "flags" are bounded, you can calculate all your conditionals as prerequisites instead of wrapping columns in them. This guarantees a high-performance index seek on whichever columns are indexed, and doesn't require writing any dynamic SQL. And it's better than writing 4 separate queries for obvious reasons.
You could have a parameter for each possible flag column, then check if the parameter is null or the value in the column is equal to the parameter. Then you pass in a 1 for the flags that you want to check and leave the others null.
select id, name, description, ...
from myTable
where (#fooFlag is null or fooFlag = #fooFlag) AND
(#barFlag is null or barFlag = #barFlag) AND
...
Honestly, though, this seems like an ideal candidate for building a dynamic LINQ query and skipping the SPROC once you get to SQL2008.
int should be accepted as varchar value
declare #CompanyID as varchar(10) = '' -- or anyother value
select * from EmployeeChatTbl chat
where chat.ConversationDetails like '%'+#searchKey+'%'
and
(
(0 = CASE WHEN (#CompanyID = '' ) THEN 0 ELSE 1 END)
or
(chat.CompanyID = #CompanyID)
)
working
when the companyID is present , then filtration based on it is done, other wise , filtration is skipped.
where
case when #value<>0 then Field else 1 end
=
case when #value<>0 then #value else 1 end