PostgreSQL UUIDv7 generation

<div class="demo"><div class="head"><b>INDEX LEAF INSERT</b><span id="uuidmode">UUIDv7</span></div><div class="stage uuid"><div class="leaf"><span>random</span><div class="slots"><i>1</i><i>2</i><i>3</i><i>4</i></div></div><div class="leaf"><span>UUIDv7</span><div class="slots"><i>1</i><i>2</i><i>3</i><i>4</i></div></div></div><div class="foot"><span id="uuidstatus">new key at the end</span><span>illustrative slots</span></div></div>

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let n=0;function tick(){document.querySelectorAll('.leaf').forEach((e,i)=>e.classList.toggle('on',i===n));document.getElementById('uuidmode').textContent=n?'UUIDv7':'random UUID';document.getElementById('uuidstatus').textContent=n?'new key at the end':'new key between old keys';n=1-n}tick();const t=setInterval(tick,1200);document.querySelector('.demo').onclick=()=>{clearInterval(t);tick()}