Iterating with For Loop through Temporary Table in PostgreSQL - sql

Question

I am trying to iterate over a Temporary Table inside of a Function, where I want to make an Update on every row.
The Temporary Table should hold all the user ID's that are getting out of the query.
After that, for every Single User it should be checked, if the percentage of the transactions with attributes is smaller than 50% of all transactions.
In the end, the account field master_segments should be updated.
My Code looks like that:
CREATE OR REPLACE FUNCTION temptable()
RETURNS VARCHAR
AS $$
BEGIN
CREATE TEMP TABLE IF NOT EXISTS testTable AS
SELECT account.sfid, transactions.transactionNumber
FROM account
INNER JOIN transactions ON account.sfid =transactions.accountsfid
INNER JOIN transactionLineItems ON transactions.transactionNumber = transactionLineItems.transactionNumber
INNER JOIN products ON transactionLineItems.USIM = products.USIM
WHERE account.gender = '1' AND (transactions.transactionDate >= current_date - interval '730' day AND products.gender = 'female' AND products.agegroup = 'adult');
FOR j IN testTable.sfid LOOP
SELECT(
(SELECT COUNT(transactions.transactionNumber)
FROM transactions
INNER JOIN account ON account.sfid = transactions.accountsfid
INNER JOIN transactionLineItems ON transactions.transactionNumber = transactionLineItems.transactionNumber
INNER JOIN products ON transactionLineItems.USIM = products.USIM
WHERE products.gender = 'male' AND products.agegroup = 'adult' AND transactions.transactionDate >= current_date - interval '730' day)*1.0 /
(SELECT COUNT(transactions.transactionNumber)
FROM transactions
WHERE transactions.transactionDate >= current_date - interval '730' day)
) < 0.5;
UPDATE account
SET account.master_segments = 'Women' WHERE account.sfid = testTable.sfid;
END LOOP;
END;
$$ LANGUAGE plpgsql;
I am getting this message:
ERROR: syntax error at or near "testTable"
LINE 14: FOR j IN testTable.sfid LOOP
Does someone has a suggestion on this?
Thanks!

Answer 1

I assume what you try to do is:
UPDATE account
SET account.master_segments = 'Women'
FROM (
SELECT account.sfid, transactions.transactionNumber
FROM account
INNER JOIN transactions ON account.sfid =transactions.accountsfid
INNER JOIN transactionLineItems ON transactions.transactionNumber = transactionLineItems.transactionNumber
INNER JOIN products ON transactionLineItems.USIM = products.USIM
WHERE account.gender = '1' AND (transactions.transactionDate >= current_date - interval '730' day AND products.gender = 'female' AND products.agegroup = 'adult')
) testtable
WHERE account.sfid = testtable.sfid

Answer 2

You don't need a subquery and you don't need to repeat the account table for this logic:
UPDATE account a
SET master_segments = 'Women'
FROM transactions t INNER JOIN
transactionLineItems tli
ON t.transactionNumber = tli.transactionNumber AND
t.transactionDate >= current_date - interval '730' day INNER JOIN
products p
ON tli.USIM = p.USIM AND
p.gender = 'female' AND
p.agegroup = 'adult'
WHERE a.gender = '1' AND a.sfid = t.sfid;
I also introduced table aliases so the query is easier to write and to read.