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<div id="cbwrap">
<!-- DOES NOT MATTER -->
<h1 id="cbtitle">Javascript SQLite</h1>
<p>Open the console.</p>
</div>
/* (X) DOES NOT MATTER */
* { box-sizing: border-box; }
body {
font-family: arial, sans-serif;
padding: 0; margin: 0; border: 0;
min-height: 100vh;
display: flex; justify-content: center; align-items: center;
background: url(https://images.unsplash.com/photo-1644325349124-d1756b79dd42?crop=entropy&cs=srgb&fm=jpg&ixid=M3wzMjM4NDZ8MHwxfHJhbmRvbXx8fHx8fHx8fDE2OTQ4NzUzNTZ8&ixlib=rb-4.0.3&q=85);
background-size: cover;
background-position: center;
backdrop-filter: blur(10px);
}
#cbwrap {
background: rgba(255, 255, 255, 0.9);
width: 600px; padding: 20px;
border-radius: 10px;
}
#cbtitle {
margin-bottom: 40px;
text-transform: uppercase;
}
#cbinfo {
padding: 10px; margin-top: 40px;
font-weight: 700; text-align: center;
}
#cbinfo a {
text-decoration: none; padding: 5px;
color: #fff; background: #a91616;
}
var demo = {
// (A) INITIALIZE
db : null, // database object
cache : null, // storage cache object
cname : "SQLDB", // cache storage name
dbname : "/demo.sqlite", // database storage name
init : async () => {
// (A1) STORAGE CACHE + SQLJS
demo.cache = await caches.open(demo.cname);
const SQL = await initSqlJs({
locateFile: filename => `https://cdnjs.cloudflare.com/ajax/libs/sql.js/1.8.0/${filename}`
});
// (A2) ATTEMPT TO LOAD DATABASE FROM STORAGE CACHE
demo.cache.match(demo.dbname).then(async r => {
// (A2-1) NOT FOUND - CREATE A NEW DATABASE
if (r==undefined) {
demo.db = new SQL.Database();
demo.db.run(`CREATE TABLE events (
id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
date TEXT NOT NULL,
text TEXT NOT NULL
)`);
demo.db.run("CREATE INDEX date ON events (date)");
await demo.export();
await demo.run();
demo.get();
}
// (A2-2) LOAD EXISTING DATABASE
else {
const buf = await r.arrayBuffer();
demo.db = new SQL.Database(new Uint8Array(buf));
demo.get();
}
});
},
// (B) EXPORT TO CACHE STORAGE
export : async () => await demo.cache.put(
demo.dbname, new Response(demo.db.export())
),
// (C) DEMO - INSERT/UPDATE EVENT
run : async () => {
// (C1) INSERT
demo.db.run(
`INSERT INTO events (date, text) VALUES (?,?), (?,?), (?,?)`, [
"2077-06-05 00:00:00", "First event.",
"2077-06-06 00:00:00", "Second event.",
"2077-06-07 00:00:00", "Third event."
]);
// (C2) UPDATE
demo.db.run(
`UPDATE events SET date=?, text=? WHERE id=?`,
["2077-06-06 00:00:00", "Second event EDITED.", 2]
);
// (C3) DELETE
demo.db.run("DELETE FROM events WHERE id=?", [1]);
// (C4) "COMMIT"
await demo.export();
},
// (D) DEMO - GET EVENT
get : () => {
// (D1) GET SINGLE ENTRY
let stmt = demo.db.prepare("SELECT * FROM events WHERE id=$id"),
res = stmt.getAsObject({$id:2});
console.log(res);
// (D2) GET MULTIPLE ENTRIES
stmt = demo.db.prepare(
`SELECT * FROM events
WHERE date BETWEEN $start AND $end`);
stmt.bind({$start:"2077-06-01 00:00:00", $end:"2077-06-08 00:00:00"})
while (stmt.step()) {
res = stmt.getAsObject();
console.log(res);
}
}
};
// (E) GO!
window.addEventListener("load", demo.init);
Also see: Tab Triggers