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From: Shaozhong SHI <shishaozhong@gmail.com>
Date: Mon, 24 Oct 2022 15:44:03 +0100
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 <CA+i5Jwa5VR7vJ=9S-9-d_3HgxQ_MmqwLW9+vqeN=jNDUVSVCHQ@mail.gmail.com>
Subject: select only 1 pair
To: pgsql-sql <pgsql-sql@lists.postgresql.org>
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There are pair ids.  Each pair is repeated.

id1   id2
1       2
2        1
3         4
4         3

How to only select 1 unique pair for each?

Regards,

David

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<div dir=3D"ltr">There are pair ids.=C2=A0 Each pair is repeated.<br><div><=
br></div><div>id1=C2=A0 =C2=A0id2</div><div>1=C2=A0 =C2=A0 =C2=A0 =C2=A02</=
div><div>2=C2=A0 =C2=A0 =C2=A0 =C2=A0 1</div><div>3=C2=A0 =C2=A0 =C2=A0 =C2=
=A0 =C2=A04</div><div>4=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A03</div><div><br></=
div><div>How to only select 1 unique pair for each?</div><div><br></div><di=
v>Regards,</div><div><br></div><div>David</div></div>

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