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Date: Sun, 5 Feb 2023 12:09:10 +0800
From: "jacktby@gmail.com" <jacktby@gmail.com>
To: pgsql-hackers <pgsql-hackers@lists.postgresql.org>
Subject: what's the meaning of key?
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<html><head><meta http-equiv=3D"content-type" content=3D"text/html; charse=
t=3Dus-ascii"><style>body { line-height: 1.5; }body { font-size: 14px; fon=
t-family: "Microsoft YaHei UI"; color: rgb(0, 0, 0); line-height: 1.5; }</=
style></head><body>=0A<div><span></span><br></div>=0A<div>I'm doing resear=
ch on heap_am, and for&nbsp;<span style=3D"background-color: transparent;"=
>heap_beginscan func, I find</span></div><div><span style=3D"background-co=
lor: transparent;">out that there is a arg called nkeys, I use some sqls a=
s examples like&nbsp;</span></div><div><span style=3D"background-color: tr=
ansparent;">'select * from t;' and 'select * from t where a&nbsp; =3D 1', =
but it is always zero,</span></div><div><span style=3D"background-color: t=
ransparent;">can you give me some descriptions for this? what's it used fo=
r?&nbsp;</span></div><hr style=3D"width: 210px; height: 1px;" color=3D"#b5=
c4df" size=3D"1" align=3D"left">=0A<div><span><div style=3D"MARGIN: 10px; =
FONT-FAMILY: verdana; FONT-SIZE: 10pt"><div>jacktby@gmail.com</div></div><=
/span></div>=0A</body></html>
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