将名称与柱状表中的 SSN 匹配

Question

thanks in advance for any advice that you might have.

This is my first time attempting to query from a columnar database, so I'm a bit uncertain as to how to write a query that gives me the results that I'm looking for.

The table ("census_data") that I'm querying from has the following types of values (41 rows total):

plan_id ssn_key        field    value
1       111111111      DOB      1732-02-22
1       111111111      DOR      1830-11-02
1       111111111      FNAME    GEORGE
1       111111111      LNAME    WASHINGTON
1       863283322      DOR      2020-03-22

As an FYI, in some cases, we might only have someone's SSN and DOB, but not their FNAME, LNAME, DOR (date of retirement), etc.

We're working with dummy data now and attempting to have queries in place for when we begin working with a large-scale data set.

We know that in some cases in the actual data set, there will be illogical data, such as a Date of Retirement ('DOR') that occurs in the future (assuming for our rules, a 'DOR' value must occur in the past in order for it to be valid).

We've written some queries that have given us the results that we're looking for, such as:

1) Give us the birthdays of all people with FNAME = 'GEORGE' and LNAME = 'WASHINGTON'

select [value] from [testdb3].[dbo].[census_data]
where ssn_key in (select ssn_key from census_data where field='LNAME' 
and value='WASHINGTON' and ssn_key in
(select ssn_key from census_data where field='FNAME' 
and [value]='GEORGE')) AND field='DOB' 

2) Give us all SSNs of people with a Date of Retirement after today

select [plan_id], [ssn_key], [field], [value] 
from [testdb3].[dbo].[census_data] as 
cd where cd.field = 'DOR'and value > GETDATE()

As a reminder, the SSN values are in the 2nd column in our table, whereas the values for DOB, FNAME, DOR, LNAME, etc. are all in the 4th column of our table.

And here's where we're stumped. We're trying to write a query that gives us the first name of anyone with a date of retirement greater than today. We've spent a few hours trying to come up with something that works and have come up empty so far. If anyone has any thoughts on what the code would be, please let me know, I would greatly appreciate it. Thank you.