sql - Get Unique Results in a query -

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im sure pretty simple t-sql guru.

i have following result table

idmain  idsecondary  textvalue 1       1            text1 1       2            text2 2       5            text3 2       6            text5

and want obtain first occurence of idmain only.

the result should this.

idmain  idsecondary  textvalue 1       1            text1 2       5            text3

how can achieve this?

you should able join sub query, in following example. assumes "first" mean lowest idsecondary:

select t.idmain, sub_t.minsecondary, t.textvalue   your_table t join   (select   idmain, min(idsecondary) minsecondary             your_table         group idmain) sub_t on (sub_t.idmain = t.idmain);

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