Is it possible to perform such a queries - sql

Question

I have SQL Server tables and I am supposed to create a query where it will be able to draw out the same data based on any combination of inputs of parameters / search conditions in a single query
For example, a user gives a model number for us to search for all products in table 1.
I would create a query as follows:
SELECT *
FROM Products
WHERE pModel = #pUserModel;
Next, another user gives us a description of the product which I then have to create another query as follows:
SELECT *
FROM Products
WHERE pDescription = #pUserDescription;
Table 1
Products (pNo, pModel, pDescription, pQty, pGlobalQty, pParent)
My issue here would be that instead of the two queries that were created based on different parameters, is there any way to create a single query where it will be able to fulfill those two search condition by both different users?

Answer 1

declare #pUserModel varchar(50)
declare #pUserDescription varchar(50)
--- if you want to search with individual search parameter than try with this.
if (#pUserModel <> '')
begin
SELECT * FROM Products WHERE pModel = #pUserModel;
end
else if (#pUserDescription <> '')
begin
SELECT * FROM Products WHERE pDescription = #pUserDescription;
end
--- if you want to combine all search parameter than try with this.
SELECT * FROM Products WHERE LTRIM(RTRIM(pModel)) = #pUserModel or LTRIM(RTRIM(pDescription)) = #pUserDescription

Answer 2

If I understand your requirement properly, you need join and OR condition
select * from Products p
left join Model m
on p.pModel=m.mModel
where (p.pModel = #pUserModel
OR p.pDescription = #pUserDescription)
Left join to return records from Products even if there is no Model associated with it. You can change it to INNER JOIN if you don't want it.

Answer 3

You can look for the trimmed length of the parameter string as part of an OR condition and always provide both parameters, even if one of them is an empty string "". Something like
SELECT
P.*
from
Products P
where
( LEN( RTRIM( #pUserModel )) = 0
OR P.pModel = #pUserModel )
OR
( LEN( RTRIM( #pUserDescription )) = 0
OR P.pDescription = #pUserDescription )
if you query such as where pDescription = '', it would fail if the description column actually HAS a value. So by wrapping each in an OR condition to say it's ok if the length of the TRIMMED parameter = 0 OR it matches the one being searched for. If you want the wild-card search, be sure to add '%'
To eliminate the OR qualifier, if your empty parameters are just '%', that will pull everything, for that respective parameters. So you could have a model = '%' and description = 'Something%'... Or vice-versa... Model = 'Some Model%' and Description = '%'
I aliased the products table as "P" to simplify readability. Especially if you have multiple tables, you should always identify where a table/column comes from for others to help.