Db2 Developer-C 11.1

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CREATE TABLE routing (
    PN INTEGER,
    Name VARCHAR(50)
);
CREATE INDEX IX_Routing_PN ON routing (PN);
INSERT INTO routing (PN, Name) 
VALUES (51000, 'Bob'),
       (52000, 'Bob'),
       (61000, 'John'),
       (62000, 'John'),
       (1000,'overlap 1'),
       (1100,'overlap 1'),
       (1010,'overlap 2'),
       (1110,'overlap 2');
CREATE VIEW my_routing AS
SELECT PN
    , LEAD(PN, 1) OVER (
        PARTITION BY Name ORDER BY PN
        ) AS NextPN
    , Name
FROM routing;
SELECT
      name
    , pn
    , nextpn
FROM my_routing
WHERE 51235 between PN and NextPN
   OR 1050 between PN and NextPN
ORDER BY
      name
    , pn
    , nextpn


NAME
PN
NEXTPN


Bob
51000
52000

overlap 1
1000
1100

overlap 2
1010
1110