CODEWITHSUNDEEP
sqlsql-serversql-server-2008group-by
user1257292
user1257292

Reputation: 51

Get consecutive values in a group identified by min and max value

I'm trying to get groups of consecutive values from a table. I've been trying to find an example about this but I haven't been able to use it in my case.

This is a small part of a table I have.

    CardID      CardSerial                  CardStateID AssignUserID Denomination
    ----------- --------------------------- ----------- ------------ -------------
    2685680     214026002                   3           81           10
    2685681     214026003                   3           81           10
    2685682     214026004                   3           81           10
    2685683     214026005                   3           81           10
    2685684     214026006                   3           81           10
    2685778     214026100                   3           81           10
    2685779     214026101                   3           81           10
    2685780     214026102                   3           81           10
    2685781     214026103                   3           81           10
    2685782     214026104                   3           81           10
    2685878     214026200                   3           81           10
    2685879     214026201                   3           81           10
    2685880     214026202                   3           81           10
    2685881     214026203                   3           81           10
    2685882     214026204                   3           81           10
    2685883     214026205                   3           81           10
    2685884     214026206                   3           81           10

The results that I'm expecting are:

    min value       max value       cant     Den
    --------------- --------------- -------- ----
    214026002       214026006        5        10
    214026100       214026104        5        10
    214026200       214026206        7        10

The hard part for me is to get a group value to make a query like

select min(cardSerial), max(cardSerial), count(*), Den
from Cards
group by Den, GROUPING_VALUE_GENERATED

Upvotes: 5

Views: 1595

Answers (2)

Girija
Girija

Reputation: 45

This query is very much useful. Can we update the minimum value against the respective groups.

Example in the table one more column as "Min_CardSerial" and the value to update for this column is "214026002" for the row between 214026002 and 214026006, 214026100 is for the rows between 214026100 and 214026104 and so on.

Upvotes: 0

MatBailie
MatBailie

Reputation: 86706

Assuming that cardSerial is an INT or other numeric data-type...

WITH
  sequenced AS 
(
  SELECT
    ROW_NUMBER() OVER (PARTITION BY Denomination ORDER BY cardSerial) AS sequence_id,
    *
  FROM
    Cards
)
SELECT
  min(cardSerial),
  max(cardSerial),
  count(*),
  Denomination
FROM
  Sequenced
GROUP BY
  Denomination,
  cardSerial - sequence_id
ORDER BY
  Denomination,
  cardSerial - sequence_id

If it's not a numeric data-type, convert it in the query to a suitably large numeric data-type to allow cardSerial - sequence_id to work.


How the cardSerial - sequence_id calculation gives something meaningful to group by...

214026002 - 01 = 214026001
214026003 - 02 = 214026001
214026004 - 03 = 214026001
214026005 - 04 = 214026001
214026006 - 05 = 214026001
214026100 - 06 = 214026094
214026101 - 07 = 214026094
214026102 - 08 = 214026094
214026103 - 09 = 214026094
214026104 - 10 = 214026094
214026200 - 11 = 214026189
214026201 - 12 = 214026189
214026202 - 13 = 214026189
214026203 - 14 = 214026189
214026204 - 15 = 214026189
214026205 - 16 = 214026189
214026206 - 17 = 214026189

Upvotes: 3

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