query riferimenti, in progress

js/dataMgr.js

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+import * as duckdb from 'https://cdn.jsdelivr.net/npm/@duckdb/duckdb-wasm@1.29.0/+esm';
+//import * as arrow from 'https://cdn.skypack.dev/apache-arrow@9'
+
+
+var rif_commentatori=[];
+var rif_autori=[];
+var rif_areetematiche=[];
+
+const JSDELIVR_BUNDLES = duckdb.getJsDelivrBundles();
+
+// Select a bundle based on browser checks
+const bundle = await duckdb.selectBundle(JSDELIVR_BUNDLES);
+
+const worker_url = URL.createObjectURL(
+  new Blob([`importScripts("${bundle.mainWorker}");`], {type: 'text/javascript'})
+);
+
+// Instantiate the asynchronus version of DuckDB-wasm
+const worker = new Worker(worker_url);
+const logger = new duckdb.ConsoleLogger();
+const db = new duckdb.AsyncDuckDB(logger, worker);
+await db.instantiate(bundle.mainModule, bundle.pthreadWorker);
+URL.revokeObjectURL(worker_url);
+
+console.log ('datamgr init done')
+
+
+//await db.registerFileURL('remote.parquet', 'http://localhost:8000/js/data/riferimenti_3.parquet', DuckDBDataProtocol.HTTP, false);
+
+/*const res = await fetch('http://localhost:8000/js/data/riferimenti_3.parquet');
+
+await db.registerFileBuffer('buffer.parquet', new Uint8Array(await res.arrayBuffer()));*/
+
+const conn = await db.connect();
+
+await conn.query(`
+    CREATE TABLE riferimenti AS
+        SELECT * FROM "https://lida.dantenetwork.it/js/data/riferimenti_3.parquet";
+	CREATE table commentatori as select distinct Com from riferimenti;
+	CREATE table autori as select distinct Aut from riferimenti order by Aut;
+	Create table areatematica as select distinct CA from riferimenti order by CA;
+`);
+
+var table=await conn.query(`
+        SELECT * FROM autori
+`);
+const result = table.toArray().map((row) => row.toJSON());
+rif_autori=result.map((x) => x['Aut']);
+console.log(rif_autori)
+await conn.close();
+const conn2 = await db.connect();
+var table=await conn2.query(`
+        SELECT * FROM commentatori
+`);
+const result2 = table.toArray().map((row) => row.toJSON());
+rif_commentatori=result2.map((x) => x['Com']);;
+console.log(rif_commentatori)
+
+var table=await conn2.query(`
+        SELECT * FROM areatematica
+`);
+const result3 = table.toArray().map((row) => row.toJSON());
+
+rif_areetematiche= result3.map((x) => x['CA']);
+console.log(rif_areetematiche)
+await conn2.close();
+
+console.log('done')