count :SQL :DB2 - sql

Question

I have this table:
CODE
IDNR
NAME
LIMIT
123
80
XXX
2019-05
123
81
XXX
2019-10
124
80
YYY
2019-01
125
80
ZZZ
2019-05
125
81
ZZZ
2019-06
125
80
ZZZ
2019-07
126
80
III
2019-05
126
80
III
2019-09
126
80
III
2019-07
I want to have a new column (Count-LIMIT ) contain how many LIMIT per code, and another contain YES if the limit are continuous and No if not.
MY RESULT that I want like:
CODE
IDNR
NAME
LIMIT
Count-Limit
CON
123
80
XXX
2019-05
2
NO
123
81
XXX
2019-10
2
NO
124
80
YYY
2019-01
1
NO
125
80
ZZZ
2019-05
3
YES
125
81
ZZZ
2019-06
3
YES
125
80
ZZZ
2019-07
3
YES
126
80
III
2019-05
3
NO
126
80
III
2019-09
3
NO
126
80
III
2019-07
3
NO
THANKS!

Answer 1

Try this:
WITH T (CODE, IDNR, NAME, LIMIT) AS
(
VALUES
(123, 80, 'XXX', '2019-05')
, (123, 81, 'XXX', '2019-10')
, (124, 80, 'YYY', '2019-01')
, (125, 80, 'ZZZ', '2019-05')
, (125, 81, 'ZZZ', '2019-06')
, (125, 80, 'ZZZ', '2019-07')
, (126, 80, 'III', '2019-05')
, (126, 80, 'III', '2019-09')
, (126, 80, 'III', '2019-07')
, (128, 80, 'AAA', '2021-01')
, (128, 80, 'AAA', '2021-03')
, (128, 80, 'AAA', '2021-05')
, (128, 80, 'AAA', '2021-07')
, (128, 80, 'AAA', '2021-08')
, (128, 80, 'AAA', '2021-09')
)
SELECT
T.*
, COUNT (1) OVER (PARTITION BY CODE) AS COUNT_LIMIT
, CASE
WHEN TO_DATE (LIMIT || '-01', 'YYYY-MM-DD') IN
(
LAG (TO_DATE (LIMIT || '-01', 'YYYY-MM-DD')) OVER (PARTITION BY CODE ORDER BY LIMIT) + 1 MONTH
, LEAD (TO_DATE (LIMIT || '-01', 'YYYY-MM-DD')) OVER (PARTITION BY CODE ORDER BY LIMIT) - 1 MONTH
)
THEN 'YES'
ELSE 'NO'
END AS CON
FROM T
ORDER BY CODE, LIMIT
The result is:
CODE
IDNR
NAME
LIMIT
COUNT_LIMIT
CON
123
80
XXX
2019-05
2
NO
123
81
XXX
2019-10
2
NO
124
80
YYY
2019-01
1
NO
125
80
ZZZ
2019-05
3
YES
125
81
ZZZ
2019-06
3
YES
125
80
ZZZ
2019-07
3
YES
126
80
III
2019-05
3
NO
126
80
III
2019-07
3
NO
126
80
III
2019-09
3
NO
128
80
AAA
2021-01
6
NO
128
80
AAA
2021-03
6
NO
128
80
AAA
2021-05
6
NO
128
80
AAA
2021-07
6
YES
128
80
AAA
2021-08
6
YES
128
80
AAA
2021-09
6
YES