T-SQL query in SQL Server - sql-server

Question

I want to write a query where this should meet the condition shown in the first screenshot. Currently, I am getting second screenshot data which is not correct. I am having a hard time achieving this.
SELECT
CONCAT(p.[prefNameFamilyName], ' ', p.[prefNameGivenName], ' ', p.[prefNameMiddleNames], ' ', pre.code, ' ', nt.code) AS PatientName,
CONCAT(pn.familyName, ' ', pn.givenName, ' ', pn.middleNames, ' ', nt.code) AS PatientAlias,
CONCAT(pa.streetAddressLine1, ' ', pc.code, ' ', sp.code, ' ', ap.code, ' ', ac.code, ' ', atp.code) AS PatientAddress
FROM
identifier.identifier I
INNER JOIN
[Patient].[Patient] p ON i.id = p.patientIdentifierId
INNER JOIN
[Patient].PatientName pn ON pn.patientId = p.id
INNER JOIN
[Identifier].[LK_NamePrefix] pre ON pre.id = p.prefNamePrefixId
INNER JOIN
[Identifier].[LK_NameType] nt ON nt.id = pn.nameTypeId
LEFT JOIN
Patient.PatientAddress a ON a.patientId = p.id
INNER JOIN
[Patient].[PatientAddress] pa ON pa.patientId = p.id
INNER JOIN
[Address].[City] pc ON pa.cityId = pc.id
LEFT JOIN
[Address].[Country] ac ON ac.id = pa.countryId
LEFT JOIN
[Address].[StateOrProvince] sp ON sp.id = pa.stateOrProvinceId
LEFT JOIN
[Address].[Postcode] ap ON ap.id = pa.postcodeId
LEFT JOIN
[Address].[AddressType] atp ON atp.id = pa.addressTypeId
WHERE
I.identifier = 'ABC123'

Answer 1

You could use common table expressions (CTE's) to isolate the joins. This solution generates row numbers for the different combinations and joins on the row numbers later on. The final step is to filter out the rows with only null values. This solution works for any combination of a name, one or more aliases and one or more addresses.
Sample data
declare #names table
(
id int,
name nvarchar(20)
);
insert into #names (id, name) values
(1, 'Bruce Wayne'),
(2, 'Peter Parker'),
(3, 'Clark Kent');
declare #aliases table
(
id int,
alias nvarchar(20)
)
insert into #aliases (id, alias) values
(1, 'Batman'),
(1, 'The bat'),
(1, 'Batty'),
(2, 'Spider-Man'),
(2, 'Spidey'),
(3, 'Superman');
declare #addresses table
(
id int,
address nvarchar(20)
);
insert into #addresses (id, address) values
(1, 'Wayne Manor'),
(1, 'The Cave'),
(2, 'Aunt May''s house'),
(3, 'The Daily Planet'),
(3, 'Krypton');
Solution
with cte_na as
(
select na.id,
na.name,
row_number() over(partition by na.id order by na.name) as nameNum
from #names na
left join #aliases al
on al.id = na.id
left join #addresses ad
on ad.id = na.id
),
cte_al as
(
select al.id,
al.alias,
row_number() over(partition by al.id order by al.alias) as aliasNum
from #aliases al
),
cte_ad as
(
select ad.id,
ad.address,
row_number() over(partition by ad.id order by ad.address) as addressNum
from #addresses ad
)
select cna.id,
cna.name,
coalesce(cal.alias, '') as alias,
coalesce(cad.address, '') as address
from cte_na cna
left join cte_al cal
on cal.id = cna.id
and cal.aliasNum = cna.nameNum
left join cte_ad cad
on cad.id = cna.id
and cad.addressNum = cna.nameNum
where not (cal.id is null and cad.id is null);
Result
id name alias address
----------- -------------------- -------------------- --------------------
1 Bruce Wayne Batman The Cave
1 Bruce Wayne Batty Wayne Manor
1 Bruce Wayne The bat
2 Peter Parker Spider-Man Aunt May's house
2 Peter Parker Spidey
3 Clark Kent Superman Krypton
3 Clark Kent The Daily Planet