How do I count items on a table?
I want to do the equivalent of this:
SELECT COUNT(*) FROM table_name;
In Convex i tried this but it seems not performant:
export const countMaterialsTable = query({
handler: async (ctx) => {
const materials = await ctx.db.query("materials").collect();
return materials.length;
},
I Installed convex cache helper thinking it may help since i dont need the counter to be that reactive.
- ConvexQueryCacheProvider (provider.tsx)
- UseQuery (hooks.ts)
import { useQuery } from "convex-helpers/react/cache/hooks";
// ...
const materials = useQuery(api.materials.countMaterialsTable);
It worked fine on the development server, but when i deployed to vercel my cache was not working ( i attached the console.log on debug mode, it loops every 5 seconds or so),
between the actual value "185" and undefined.
3 Replies
I'd recommend keeping a computed field on your table that stores the count. Increment on insert, decrement on delete. Everything is transactional so it just works.
Or, rather, not on that same table, but a separate table.
also a potential feature request for the table to be able to have associated metadata
so i should just make a metadata table? seems ok