I get an error in the query below. Why ?
DECLARE @Vr varchar(50);
SET @Vr = N'Infos';
IF @Vr = FAR
UPDATE MyTable
SET TAR = @Vr
Error - Invalid column name 'FAR'.
I am using the right database and right table. Then, why does this happen ?
My logic is if Column Far = variable Vr, then update Column TAR.
This is the true code:
DECLARE @Vr varchar(50);
SET @Vr = N'Infos';
IF @Vr = (select far from <table_name>)
Begin
UPDATE MyTable
SET TAR = @Vr
END
DECLARE @Vr varchar(50);
SET @Vr = N'Infos';
-- IF @Vr = FAR
IF ( select Count(*) from mytable where ColumnFar =@Vr) >0
BEGIN
UPDATE MyTable
SET TAR = @Vr where ColumnFar =@Var
END
ELSE
BEGIN
-- Goes your condition
END
Or use CASE
DECLARE @Vr varchar(50);
SET @Vr = N'Infos';
UPDATE MyTable
SET TAR =
CASE
WHEN ( @Vr = FAR)
THEN 'FAR'
Else
NULL -- Or any other value you want.
END
In your case, you are checking the column name and not that particular column's value. I suggest you try dynamic sql. This link can be useful.
As far as I've understood, if your @Vr = 'FAR' then update field TAR else do something else. In that case, see my below query
DECLARE @SQL NVARCHAR(MAX)
DECLARE @valueToBeUpdatedInYourColumn nvarchar(100)
set @valueToBeUpdatedInYourColumn = 'this value will be your updated value'
SET @Vr = 'Infos';
IF @Vr = 'FAR'
BEGIN
SET @SQL = '
UPDATE MyTable
SET TAR= '''+@valueToBeUpdatedInYourColumn+'''
'
EXEC(@SQL)
END
ELSE
BEGIN
...
END
The number of single quotes ' is very important
You need BEGIN/END for your IF statement
DECLARE @Vr varchar(50);
SET @Vr = N'Infos';
UPDATE MyTable
SET TAR = @Vr
WHERE FAR = @vr
EDIT:
Use a where clause instead of an IF block.
IF @Vr = FAR UPDATE MyTable SET TAR = @VrtoUPDATE MyTable SET TAR = @Vr WHERE FAR = @Vr.