sql - Select rows with unique attribute -

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i have following table

ind_id      name                 value       date ----------- -------------------- ----------- ---------- 1                              10          2010-01-01 1                              20          2010-01-02 1                              30          2010-01-03 2           b                    40          2010-01-01 2           b                    50          2010-01-02 2           b                    60          2010-01-03 2           b                    70          2010-01-04 3           c                    80          2010-01-01 3           c                    90          2010-01-02 3           c                    100         2010-01-03 3           c                    110         2010-01-04 3           c                    120         2010-01-05 4           d                    130         2010-01-05

how can select rows unique ind_id attribute? no matter rows each ind_id. need 4 rows in result set. i'm using sql server 2008. thanks

for this, want use windows functions:

select ind_id, name, value, date (select t.*, row_number() on (partition ind_id order (select null)) seqnum       t      ) t seqnum = 1;

if want ones appear once, use:

select ind_id, name, value, date (select t.*, count(*) on (partition ind_id) numinds       t      ) t numinds = 1

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