在DB for SQL中以日期格式联接3个表

Question

I am attempting to join 3 tables together in SQL, to no avail. My code is below:

SELECT "Trade Details 2".Portfolio, 
"Trade Details 2".CONTRACT_ID, 
DATE("Trade Details 2".START_DATE) as START_DATE, 
DATE(substr("Trade Details 2".MATURITY_DATE, 0, 5) || '-' || substr("Trade 
Details 2".MATURITY_DATE, 5,2) || '-' ||    substr("Trade Details 
2".MATURITY_DATE, 7, 9)) as MATURITY_DATE, 
"Trade Details 2".NOTIONAL1,
"Trade Details 2".CONTRACT_NPV,
"Trade Details".TERM
"FX SPOT".Mid
JOIN "Trade Details" ON "Trade Details 2".CONTRACT_ID="Trade Details".FCC_ID
INNER JOIN "FX SPOT" ON "FX SPOT".MID
WHERE "Trade Details 2".CONTRACT_ID="Trade Details".FCC_ID and
("Trade Details 2".NOTIONAL1 > "0.0") and
("Trade Details 2".MATURITY_DATE > DATE(substr('20180622', 0, 5) || '-' || 
substr('20180622', 5,2) || '-' ||    substr('20180622', 7, 9)) )
ORDER BY CONTRACT_ID asc

If I just try to adjoin two tables, taking out all the things relating to "FX Spot".Mid, I get this

SELECT "Trade Details 2".Portfolio, 
"Trade Details 2".CONTRACT_ID, 
DATE("Trade Details 2".START_DATE) as START_DATE, 
DATE(substr("Trade Details 2".MATURITY_DATE, 0, 5) || '-' || substr("Trade Details 2".MATURITY_DATE, 5,2) || '-' ||    substr("Trade Details 2".MATURITY_DATE, 7, 9)) as MATURITY_DATE, 
"Trade Details 2".NOTIONAL1,
"Trade Details 2".CONTRACT_NPV,
"Trade Details".TERM
FROM "Trade Details 2" 
JOIN "Trade Details" 
WHERE "Trade Details 2".CONTRACT_ID="Trade Details".FCC_ID and
("Trade Details 2".NOTIONAL1 > "0.0") and
("Trade Details 2".MATURITY_DATE > DATE(substr('20180622', 0, 5) || '-' || substr('20180622', 5,2) || '-' ||    substr('20180622', 7, 9)) )
ORDER BY CONTRACT_ID asc

which works.

However, as soon as I attempt to add the third column, I get a syntax error near "." I followed how to join 3 tables to a tee, so I don't see what I'm doing wrong here.

Answer 1

Since you only want one value from FX SPOT, just append that value to every row in your SELECT, probably would be much more efficient yet to just set the value from your FX SPOT select to a variable and append the variable to your table join SELECT, Since I just found out that you can't declare a variable like below in SQLLite just do the Subquery inside your Table Join Select statment:

--Can't do this in SQLLite
--DECLARE @mId INT = (SELECT TOP 1 "FX SPOT".Mid FROM "FX SPOT");

SELECT "Trade Details 2".Portfolio, 
"Trade Details 2".CONTRACT_ID, 
DATE("Trade Details 2".START_DATE) as START_DATE, 
DATE(substr("Trade Details 2".MATURITY_DATE, 0, 5) || '-' || substr("Trade 
Details 2".MATURITY_DATE, 5,2) || '-' ||    substr("Trade Details 
2".MATURITY_DATE, 7, 9)) as MATURITY_DATE, 
"Trade Details 2".NOTIONAL1,
"Trade Details 2".CONTRACT_NPV,
"Trade Details".TERM,
--"FX SPOT".Mid REPLACE THIS WITH THE NEXT LINE
--@mId AS MID
(SELECT TOP 1 "FX SPOT".Mid FROM "FX SPOT") AS MID  --Reverted back to this
JOIN "Trade Details" ON "Trade Details 2".CONTRACT_ID="Trade Details".FCC_ID
--INNER JOIN "FX SPOT" ON "FX SPOT".MID DONT NEED THIS Since you have no relationship between this value and other tables
WHERE "Trade Details 2".CONTRACT_ID="Trade Details".FCC_ID and
("Trade Details 2".NOTIONAL1 > "0.0") and
("Trade Details 2".MATURITY_DATE > DATE(substr('20180622', 0, 5) || '-' || 
substr('20180622', 5,2) || '-' ||    substr('20180622', 7, 9)) )
ORDER BY CONTRACT_ID asc