SQL: how can I set a variable in this context? - sql

I'm trying to set a couple of variables, one is a name of the table (#table), the other one is a string.
I've got the error message:
Must declare the table variable "#table".
as far as I could understand it's because I must use #table as a table variable, but I just need it as a string
declare #a varchar(50);
declare #table varchar(100);
select #table =
case
WHEN Version = 'Advanced' THEN ("tableadv")
WHEN Version = 'Professional' THEN ("tablepro")
WHEN Version = 'Light' THEN ("tablelight")
WHEN Version = 'Short' THEN ("tableshort")
END
FROM partno where inpn=3
set #a = (select top (1) LicenseNumber from #table where used is null)
insert into seriali (LicenseNumber, idpn, serdgtrace)
select #a, 2, 'DAT-enrico'
update #table set used = 1 where LicenseNumber=#a
any help will be appreciated.
Many thanks,
enrico

You need table variable not only variable to store more values with more columns not just single value :
declare #table table (
#col int,
. . .
)
insert into #table (col)
select case WHEN Version = 'Advanced' THEN 'tableadv'
WHEN Version = 'Professional' THEN 'tablepro'
WHEN Version = 'Light' THEN 'tablelight'
WHEN Version = 'Short' THEN 'tableshort'
end
from partno
where inpn = 3

hello Yogesh and thanks for the answer,
anyway I need this case structure to pick the right table name based on a field in another table.
Then I have to pass this value to update the right table;
set #a = (select top (1) LicenseNumber from #table where used is null)
update #table set used = 1 where LicenseNumber=#a
I don't need to build a table variable with one of the case values in a record, because I won't be able to pass the right table name either
Many thanks,
Enrico

Related

SQL search in two columns with one combined value

I will try to demonstrate what I am trying to achieve. This is an oversimplified example for my case.
Suppose I have a table contains two columns
ID YEAR
--- ----
1 2017
2 2018
and I have a search term 2017 / 1
What I want to do is something like this
select * from table where 'YEAR / ID' LIKE '%searchterm%'
Is this possible ?
Thanks in advance.
In my opinion the most effective way is:
Firstly divide String x = "2017 / 1" to two int values int year = 2017, int id = 1. I don't know what kind of programing language you are using but all of programing languages have special functions to make it easily (between all values you have '/').
Then use this query:
Select *
from table
where year = 2017
and id = 1
Use Below query, I have considered your search text format as 2017 / 1.
DECLARE #tblTest AS Table
(
Id INT,
YearNo INT
)
INSERT INTO #tblTest values (1,2017)
INSERT INTO #tblTest values (2,2018)
INSERT INTO #tblTest values (3,2017)
INSERT INTO #tblTest values (4,2018)
DECLARE #searchterm VARCHAR(50)='2017 / 1'
LEFT will give you string starting from left position to applied length.
RIGHT will give you string starting from right position to applied length
SELECT
*
FROM #tblTest
WHERE YearNo=LEFT(#searchterm,4)
AND Id = REPLACE(RIGHT(#searchterm,LEN(#searchterm)-(CHARINDEX('/',(REPLACE(#searchterm, ' ', ''))))),'/','')
If your database compatibility could be 130 then You can Try String_Split ref https://learn.microsoft.com/en-us/sql/t-sql/functions/string-split-transact-sql
Sql most long awaited function (as msdn says)
Declare #tbl table (id int Identity(1,1), value nvarchar(5))
Insert into #tbl ([value]) SELECT value from STRING_SPLIT(#searchstring,'/')
Declare #id int
Select #id = cast(value as int) from #tbl where id=2 --will give 1
Declare #value int
Select #id = cast(value as int) from #tbl where id=1 --ill give 2017
-- —now use them in sql
select * from table where YEAR=#value and ID = #id
You are going to screw up the performance if you do anything like below
select * from table where 'YEAR / ID' LIKE '%searchterm%'
Best way is you can split your search and supply to respective col
Declare #Search varchar(15)='2017/1'
Declare #Year int = (select LEFT(#Search,CHARINDEX('/',#search)-1))
Declare #month int = (select Right(#Search,(len(#search) -CHARINDEX('/',#search))))
select * from #temp where id=#month and year=#Year
Try this code :
select * from table where YEAR + ' / ' + ID LIKE '%searchterm%'
this query will run, but it will perform very poor.

How to add an update statement value to a variable?

I want to save data in a variable and use it later in a procedure.
UPDATE acc_Account
SET acc_Account.CompanyID = ( SELECT TOP 1
utl_Company.CompanyID
FROM utl_Company
ORDER BY CompanyID DESC
)
WHERE acc_Account.AccountNumber = #AccountNumber
how can I save the CompanyID in a variable to use it in an insert statement later on?
Have this in the beginning of your code:
declare #var varchar(20) -- change the data type according to your needs
set #var = (SELECT TOP 1 utl_Company.CompanyID FROM utl_Company ORDER BY CompanyID DESC)
Create a select local variable before the update statement, then set it, then use it.
DECLARE #companyID INT;
SELECT #companyID = "YOUR QUERY";
I think the efficient way would be using OUTPUT clause
DECLARE #TAB TABLE (CompanyID BIGINT )
UPDATE acc_Account
SET acc_Account.CompanyID = (
SELECT max(CompanyID) FROM utl_Company
)
output inserted.CompanyID into #TAB
WHERE acc_Account.AccountNumber = #AccountNumber
SELECT * FROM #TAB

Need to use `IN` for multiple string value in static query

SELECT *
FROM #empInfo
WHERE source IN (CASE WHEN #source = 'Mint' THEN 'Mint, Ming' ELSE #source END)
I am trying in the way as above.
CREATE TABLE #empInfo
(
id INT IDENTITY(1, 1),
ename VARCHAR(50),
source VARCHAR(50)
)
INSERT INTO #empInfo
VALUES ('Jon', 'Mint'), ('Jack', 'Ryan'), ('Jackie', 'Ming'),
('Jeny', 'Wing'), ('Jen', 'Wing')
DECLARE #source VARCHAR(50)
SET #source = 'Mint'
From the above what if want is, if the value Mint comes in the #source then it has to search for Mint,Ming else what comes in #source. #source always hold single value.
I have to apply this logic in very large query which is not dynamic nor I can make it, so please provide me the solution for this case if any.
Sorry, if it's not possible without dynamic query.
Thank you very much in advance.
SELECT * FROM #empInfo
WHERE (#source = 'Mint' and source in ('Mint','Ming'))
OR (#source <> 'Mint' and source = #source)
Remember that an IN clause needs separate string values. So you can't use a comma separated list in #source
A shorter version of the above query would be
SELECT * FROM #empInfo
WHERE #source = source
OR (#source = 'Mint' and source = 'Ming')

Nested update SQL Server and SELECT

I need to have a query as below:
SELECT top (1) #AddressRepeatNum=a.CheckNumber FROM(
UPDATE dbo.SearchList SET CheckNumber=CheckNumber+1
OUTPUT inserted.CheckNumber AS CheckNumber
WHERE PageAddress=#Address and CheckNumber<6
) as a
but it doesn't work. How should I rewrite it to work?
In a simple word, I want to add one to a column of my table and then if it was larger than 5 then do something
You cannot do a select directly on an update like that. You insert the output information to a table variable and then you select from the table variable.
DECLARE #AddressRepeatNum INT, #Address varchar (500) = 'Test'
DECLARE #Check table (checknumber INT)
UPDATE dbo.SearchList SET CheckNumber=CheckNumber+1
OUTPUT inserted.CheckNumber into #Check
WHERE PageAddress=#Address and CheckNumber<6
SELECT TOP (1) #AddressRepeatNum=CheckNumber
FROM #check
ORDER BY CheckNumber

Define variable to use with IN operator (T-SQL)

I have a Transact-SQL query that uses the IN operator. Something like this:
select * from myTable where myColumn in (1,2,3,4)
Is there a way to define a variable to hold the entire list "(1,2,3,4)"? How should I define it?
declare #myList {data type}
set #myList = (1,2,3,4)
select * from myTable where myColumn in #myList
DECLARE #MyList TABLE (Value INT)
INSERT INTO #MyList VALUES (1)
INSERT INTO #MyList VALUES (2)
INSERT INTO #MyList VALUES (3)
INSERT INTO #MyList VALUES (4)
SELECT *
FROM MyTable
WHERE MyColumn IN (SELECT Value FROM #MyList)
DECLARE #mylist TABLE (Id int)
INSERT INTO #mylist
SELECT id FROM (VALUES (1),(2),(3),(4),(5)) AS tbl(id)
SELECT * FROM Mytable WHERE theColumn IN (select id from #mylist)
There are two ways to tackle dynamic csv lists for TSQL queries:
1) Using an inner select
SELECT * FROM myTable WHERE myColumn in (SELECT id FROM myIdTable WHERE id > 10)
2) Using dynamically concatenated TSQL
DECLARE #sql varchar(max)
declare #list varchar(256)
select #list = '1,2,3'
SELECT #sql = 'SELECT * FROM myTable WHERE myColumn in (' + #list + ')'
exec sp_executeSQL #sql
3) A possible third option is table variables. If you have SQl Server 2005 you can use a table variable. If your on Sql Server 2008 you can even pass whole table variables in as a parameter to stored procedures and use it in a join or as a subselect in the IN clause.
DECLARE #list TABLE (Id INT)
INSERT INTO #list(Id)
SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4
SELECT
*
FROM
myTable
JOIN #list l ON myTable.myColumn = l.Id
SELECT
*
FROM
myTable
WHERE
myColumn IN (SELECT Id FROM #list)
Use a function like this:
CREATE function [dbo].[list_to_table] (#list varchar(4000))
returns #tab table (item varchar(100))
begin
if CHARINDEX(',',#list) = 0 or CHARINDEX(',',#list) is null
begin
insert into #tab (item) values (#list);
return;
end
declare #c_pos int;
declare #n_pos int;
declare #l_pos int;
set #c_pos = 0;
set #n_pos = CHARINDEX(',',#list,#c_pos);
while #n_pos > 0
begin
insert into #tab (item) values (SUBSTRING(#list,#c_pos+1,#n_pos - #c_pos-1));
set #c_pos = #n_pos;
set #l_pos = #n_pos;
set #n_pos = CHARINDEX(',',#list,#c_pos+1);
end;
insert into #tab (item) values (SUBSTRING(#list,#l_pos+1,4000));
return;
end;
Instead of using like, you make an inner join with the table returned by the function:
select * from table_1 where id in ('a','b','c')
becomes
select * from table_1 a inner join [dbo].[list_to_table] ('a,b,c') b on (a.id = b.item)
In an unindexed 1M record table the second version took about half the time...
I know this is old now but TSQL => 2016, you can use STRING_SPLIT:
DECLARE #InList varchar(255) = 'This;Is;My;List';
WITH InList (Item) AS (
SELECT value FROM STRING_SPLIT(#InList, ';')
)
SELECT *
FROM [Table]
WHERE [Item] IN (SELECT Tag FROM InList)
Starting with SQL2017 you can use STRING_SPLIT and do this:
declare #myList nvarchar(MAX)
set #myList = '1,2,3,4'
select * from myTable where myColumn in (select value from STRING_SPLIT(#myList,','))
DECLARE #myList TABLE (Id BIGINT) INSERT INTO #myList(Id) VALUES (1),(2),(3),(4);
select * from myTable where myColumn in(select Id from #myList)
Please note that for long list or production systems it's not recommended to use this way as it may be much more slower than simple INoperator like someColumnName in (1,2,3,4) (tested using 8000+ items list)
slight improvement on #LukeH, there is no need to repeat the "INSERT INTO":
and #realPT's answer - no need to have the SELECT:
DECLARE #MyList TABLE (Value INT)
INSERT INTO #MyList VALUES (1),(2),(3),(4)
SELECT * FROM MyTable
WHERE MyColumn IN (SELECT Value FROM #MyList)
No, there is no such type. But there are some choices:
Dynamically generated queries (sp_executesql)
Temporary tables
Table-type variables (closest thing that there is to a list)
Create an XML string and then convert it to a table with the XML functions (really awkward and roundabout, unless you have an XML to start with)
None of these are really elegant, but that's the best there is.
If you want to do this without using a second table, you can do a LIKE comparison with a CAST:
DECLARE #myList varchar(15)
SET #myList = ',1,2,3,4,'
SELECT *
FROM myTable
WHERE #myList LIKE '%,' + CAST(myColumn AS varchar(15)) + ',%'
If the field you're comparing is already a string then you won't need to CAST.
Surrounding both the column match and each unique value in commas will ensure an exact match. Otherwise, a value of 1 would be found in a list containing ',4,2,15,'
As no one mentioned it before, starting from Sql Server 2016 you can also use json arrays and OPENJSON (Transact-SQL):
declare #filter nvarchar(max) = '[1,2]'
select *
from dbo.Test as t
where
exists (select * from openjson(#filter) as tt where tt.[value] = t.id)
You can test it in
sql fiddle demo
You can also cover more complicated cases with json easier - see Search list of values and range in SQL using WHERE IN clause with SQL variable?
This one uses PATINDEX to match ids from a table to a non-digit delimited integer list.
-- Given a string #myList containing character delimited integers
-- (supports any non digit delimiter)
DECLARE #myList VARCHAR(MAX) = '1,2,3,4,42'
SELECT * FROM [MyTable]
WHERE
-- When the Id is at the leftmost position
-- (nothing to its left and anything to its right after a non digit char)
PATINDEX(CAST([Id] AS VARCHAR)+'[^0-9]%', #myList)>0
OR
-- When the Id is at the rightmost position
-- (anything to its left before a non digit char and nothing to its right)
PATINDEX('%[^0-9]'+CAST([Id] AS VARCHAR), #myList)>0
OR
-- When the Id is between two delimiters
-- (anything to its left and right after two non digit chars)
PATINDEX('%[^0-9]'+CAST([Id] AS VARCHAR)+'[^0-9]%', #myList)>0
OR
-- When the Id is equal to the list
-- (if there is only one Id in the list)
CAST([Id] AS VARCHAR)=#myList
Notes:
when casting as varchar and not specifying byte size in parentheses the default length is 30
% (wildcard) will match any string of zero or more characters
^ (wildcard) not to match
[^0-9] will match any non digit character
PATINDEX is an SQL standard function that returns the position of a pattern in a string
DECLARE #StatusList varchar(MAX);
SET #StatusList='1,2,3,4';
DECLARE #Status SYS_INTEGERS;
INSERT INTO #Status
SELECT Value
FROM dbo.SYS_SPLITTOINTEGERS_FN(#StatusList, ',');
SELECT Value From #Status;
Most of these seem to focus on separating-out each INT into its own parenthetical, for example:
(1),(2),(3), and so on...
That isn't always convenient. Especially since, many times, you already start with a comma-separated list, for example:
(1,2,3,...) and so on...
In these situations, you may care to do something more like this:
DECLARE #ListOfIds TABLE (DocumentId INT);
INSERT INTO #ListOfIds
SELECT Id FROM [dbo].[Document] WHERE Id IN (206,235,255,257,267,365)
SELECT * FROM #ListOfIds
I like this method because, more often than not, I am trying to work with IDs that should already exist in a table.
My experience with a commonly proposed technique offered here,
SELECT * FROM Mytable WHERE myColumn IN (select id from #mylist)
is that it induces a major performance degradation if the primary data table (Mytable) includes a very large number of records. Presumably, that is because the IN operator’s list-subquery is re-executed for every record in the data table.
I’m not seeing any offered solution here that provides the same functional result by avoiding the IN operator entirely. The general problem isn’t a need for a parameterized IN operation, it’s a need for a parameterized inclusion constraint. My favored technique for that is to implement it using an (inner) join:
DECLARE #myList varchar(50) /* BEWARE: if too small, no error, just missing data! */
SET #myList = '1,2,3,4'
SELECT *
FROM myTable
JOIN STRING_SPLIT(#myList,',') MyList_Tbl
ON myColumn = MyList_Tbl.Value
It is so much faster because the generation of the constraint-list table (MyList_Tbl) is executed only once for the entire query execution. Typically, for large data sets, this technique executes at least five times faster than the functionally equivalent parameterized IN operator solutions, like those offered here.
I think you'll have to declare a string and then execute that SQL string.
Have a look at sp_executeSQL