Postgres 9.5

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CREATE TABLE tbl (id int, customer_id text, item text, value text, timestamp timestamp);    
INSERT INTO tbl VALUES
(1, '001', 'price', '1000', '2021-11-01 01:00:00'),
(2, '001', 'price', '1500', '2021-11-02 01:00:00'),
(3, '001', 'price', '1400', '2021-11-03 01:00:00'),
(4, '001', 'condition', 'good', '2021-11-01 01:00:00'),
(5, '001', 'condition', 'good', '2021-11-02 01:00:00'),
(6, '001', 'condition', 'ok', '2021-11-03 01:00:00'),
(7, '001', 'feeling', 'sad', '2021-11-01 01:00:00'),
(8, '001', 'feeling', 'angry', '2021-11-02 01:00:00'),
(9, '001', 'feeling', 'fine', '2021-11-03 01:00:00'),
(10, '002', 'price', '1200', '2021-11-01 01:00:00'),
(11, '002', 'price', '1600', '2021-11-02 01:00:00'),
(12, '002', 'price', '2000', '2021-11-03 01:00:00'),
(13, '002', 'weather', 'sunny', '2021-11-01 01:00:00'),
(14, '002', 'weather', 'rain', '2021-11-02 01:00:00'),
(15, '002', 'price', '1900', '2021-11-04 01:00:00'),
(16, '002', 'feeling', 'sad', '2021-11-01 01:00:00'),
(17, '002', 'feeling', 'angry', '2021-11-02 01:00:00'),
(18, '002', 'feeling', 'fine', '2021-11-03 01:00:00'),
(19, '003', 'price', '1000', '2021-11-01 01:00:00'),
(20, '003', 'price', '1500', '2021-11-02 01:00:00'),
(21, '003', 'price', '2000', '2021-11-03 01:00:00'),
(22, '003', 'condition', 'ok', '2021-11-01 01:00:00'),
(23, '003', 'weather', 'rain', '2021-11-02 01:00:00'),
(24, '003', 'condition', 'bad', '2021-11-03 01:00:00'),
(25, '003', 'feeling', 'fine', '2021-11-01 01:00:00'),
(26, '003', 'weather', 'sunny', '2021-11-03 01:00:00'),
(27, '003', 'feeling', 'sad', '2021-11-03 01:00:00')
;

CREATE TEMP TABLE customer (customer_id text PRIMARY KEY);
INSERT INTO customer VALUES
  ('001')
, ('002')
, ('003')
;
27 rows affected

3 rows affected

SELECT customer_id
     , max(value) FILTER (WHERE item = 'condition') AS condition
     , max(value) FILTER (WHERE item = 'price')     AS price
     , max(value) FILTER (WHERE item = 'feeling')   AS feeling
     , max(value) FILTER (WHERE item = 'weather')   AS weather
FROM  (
   SELECT customer_id, item, value
        , row_number() OVER (PARTITION BY customer_id, item ORDER BY t.timestamp DESC) AS rn
   FROM   tbl t
   WHERE  item = ANY ('{condition,price,feeling,weather}')  -- correspondig to the above
   ) t1
WHERE  rn = 1
GROUP  BY 1;


customer_id
condition
price
feeling
weather


001
ok
1400
fine
null

002
null
1900
fine
rain

003
bad
2000
sad
sunny


SELECT *
FROM   crosstab(
   $$
   SELECT customer_id, item, value
   FROM  (
      SELECT customer_id, item, value
           , row_number() OVER (PARTITION BY customer_id, item ORDER BY t.timestamp DESC) AS rn
      FROM   tbl t
      WHERE  item = ANY ('{condition,price,feeling,weather}')  -- your items here ...
      ) t1
   WHERE  rn = 1
   ORDER  BY customer_id, item
   $$
 , $$SELECT unnest('{condition,price,feeling,weather}'::text[])$$  -- ... here ...
   ) AS ct (customer_id text, condition text, price text, feeling text, weather text);  -- ... and here ...


customer_id
condition
price
feeling
weather


001
ok
1400
fine
null

002
null
1900
fine
rain

003
bad
2000
sad
sunny


-- Faster for few customers and/or few items and/or many rows per (costomer_id, item)
SELECT *
FROM  (SELECT customer_id FROM customer) c
LEFT   JOIN LATERAL (
   SELECT value AS condition
   FROM   tbl t
   WHERE  t.customer_id = c.customer_id
   AND    t.item = 'condition'
   ORDER  BY t.timestamp DESC
   LIMIT  1
   ) AS t1 ON true
LEFT   JOIN LATERAL (
   SELECT value AS price
   FROM   tbl t
   WHERE  t.customer_id = c.customer_id
   AND    t.item = 'price'
   ORDER  BY t.timestamp DESC
   LIMIT  1
   ) AS t2 ON true
LEFT   JOIN LATERAL (
   SELECT value AS feeling
   FROM   tbl t
   WHERE  t.customer_id = c.customer_id
   AND    t.item = 'feeling'
   ORDER  BY t.timestamp DESC
   LIMIT  1
   ) AS t3 ON true
LEFT   JOIN LATERAL (
   SELECT value AS weather
   FROM   tbl t
   WHERE  t.customer_id = c.customer_id
   AND    t.item = 'weather'
   ORDER  BY t.timestamp DESC
   LIMIT  1
   ) AS t4 ON true
-- more?
ORDER  BY customer_id;  -- optional


customer_id
condition
price
feeling
weather


001
ok
1400
fine
null

002
null
1900
fine
rain

003
bad
2000
sad
sunny


SELECT c.customer_id
     , (SELECT value FROM tbl t WHERE t.customer_id = c.customer_id AND t.item = 'condition' ORDER BY t.timestamp DESC LIMIT 1) AS condition
     , (SELECT value FROM tbl t WHERE t.customer_id = c.customer_id AND t.item = 'price'     ORDER BY t.timestamp DESC LIMIT 1) AS price
     , (SELECT value FROM tbl t WHERE t.customer_id = c.customer_id AND t.item = 'feeling'   ORDER BY t.timestamp DESC LIMIT 1) AS feeling
     , (SELECT value FROM tbl t WHERE t.customer_id = c.customer_id AND t.item = 'weather'   ORDER BY t.timestamp DESC LIMIT 1) AS weather
FROM   customer c;


customer_id
condition
price
feeling
weather


001
ok
1400
fine
null

002
null
1900
fine
rain

003
bad
2000
sad
sunny