Both the worker has colo: "SIN" and the D1 instance has colo: "SIN" when checking the raw json in t

Both the worker has colo: "SIN" and the D1 instance has colo: "SIN" when checking the raw json in the trace. So my understanding of that would be that they are both running in singapore, and as singapore is a small place (I get 5ms latency pinging 1.1.1.1) I would think that a call within / or across datacenters in singapore should be < 10ms

Screenshot_2025-11-27_at_10.44.25_PM.png

tobystrOP•11/27/25, 2:47 PM

Also I enabled smart placement which I believe should put the worker next to the D1 instance (could be wrong on this)

tobystrOP•11/27/25, 2:47 PM

And for cold start, shouldn't that really just hit the first query in the waterfall

Ttobystr Both the worker has colo: "SIN" and the D1 instance has colo: "SIN" when checki...

Chaika•11/27/25, 2:49 PM

That's the colo the request/span is running in, not the location of the D1 db. You can see how it's outside of the d1/binding block, def a bit confusing though

Ttobystr Also I enabled smart placement which I believe should put the worker next to the...

Chaika•11/27/25, 2:52 PM

In the original version of Smart Placement it did just place it in the same region/location as the D1 DB. Now it's more dynamic/actually looking at latency but should eventually come close-ish if you have enough requests. In your Worker overview you can see Placement Performance, to see if it placed it
and yea cold start would only be after a min or so delay after not sending requests

tobystrOP•11/27/25, 2:54 PM

Ok so I enabled read replication and that helped a lot, so the D1 must have been placed in far away land somewhere

tobystrOP•11/27/25, 2:54 PM

Thanks for pointing me in right direction

Ttobystr Ok so I enabled read replication and that helped a lot, so the D1 must have been...

Chaika•11/27/25, 3:07 PM

It creates a read-only replica in the same region as the primary, so it was likely just placed closer I'd guess. Interesting though, yea Asia Pacific is a bit of a messy region.
Afaik D1 doesn't actually expose the underlying placement of the instances anywhere, you can only tell by poking each location and looking at latency

CChaika That's the colo the request/span is running in, not the location of the D1 db. Y...

lambrospetrou•11/27/25, 4:51 PM

We are planning to add colocolo airport code in the D1 query responses as well, similar to served_by_regionserved_by_region. It's annoying to not know where your DB is located (I know, we should do this sooner!).

So, you will have full transparency on where it is located for every query (and where it's moving when it moves). Replicas will also be reporting their own location if they serve queries themselves.

Llambrospetrou We are planning to add `colo` airport code in the D1 query responses as well, si...

Chaika•11/27/25, 5:00 PM

That would be super helpful, espec for Asia Pacific region :MeowHeartCloudflare:

MMatthew Something weird is going with D1 performance for me. Observability shows that ev...

Matthew•11/27/25, 6:53 PM

Around 7am UTC, my D1 database started performing normally - with P99(durationMS) falling to ~400ms - but now (7pm UTC) it's getting worse again, P99(durationMS) is 4 seconds and rising. Nothing about my queries is changing, the SQLite query latency is <3ms. Anyone seen this before, and any ideas what to do? Noisy neighbours seems a possibility. There may be some fragmentation issues (I dropped a couple of large tables), but that feels like it would show up in query latency.

CChaika That would be super helpful, espec for Asia Pacific region :MeowHeartCloudflare:

tobystrOP•11/28/25, 12:18 AM

Correct me if I’m wrong but currently the D1 instances don’t move right? Once created in zone within a region they stay there?

I think it would be helpful to be able to just say run this worker next to my d1 because for APAC especially you end up with the traces above if run far apart. Then if it turns out traffic is primarily coming from somewhere else then they could move in tandem to keep latency down

Manuel Ogomigo•11/28/25, 11:16 AM

out of memory: SQLITE_NOMEM

I'm facing this issue, I'm using D1 to keep track of requests for my api, and now I'm getting more and more requests more than 10m records reaching my 10gb limit.

I'm trying to delete them but getting that error out of memory is there any better way to delete them without issues?

MManuel Ogomigo out of memory: SQLITE_NOMEM I'm facing this issue, I'm using D1 to keep track o...

Florent•11/28/25, 12:17 PM

You can try to delete the rows in multiple batches and not all at once.

Ttobystr Correct me if I’m wrong but currently the D1 instances don’t move right? Once cr...

Florent•11/28/25, 12:18 PM

They should stay in the same region, but they can move between different colos

FFlorent You can try to delete the rows in multiple batches and not all at once.

Manuel Ogomigo•11/28/25, 12:33 PM

I'm doing that already, but it's taking so much time trying to delete 10M records

also do you think Workers analytic engine will be good for my usecase, after tracking every day, I group the data and send to another d1, and schedule a cron to delete the rows in batches but again it takes so much time and doesn't delete all the records for that day.

with the analytics Engine if it's possible can we delete all at once (eg for a day 1-2M records) without the limits?

tobystrOP•11/28/25, 4:03 PM

@Manuel Ogomigo you could try to create a table per day and then just drop it. The benefit of that is I also think you wouldn't pay for the deletes

Manuel Ogomigo•11/28/25, 4:06 PM

Oh this is a good idea

, I’ll work on that. Thank you so much

Peppineddu5•11/28/25, 4:07 PM

HI, I'm looking for a good way to distinguish between dev mode and production mode.
I'm currently working on a project in Astro and have connected it to d1, but I don't understand how to use local sqlite.
I currently have a drizzle.config.local.ts file with the following :

import { defineConfig } from ‘drizzle-kit’;

export default defineConfig({
    out: ‘./src/server/db/migrations’,
    schema: ‘./src/server/db/schema/index.ts’,
    dialect: ‘sqlite’,
    dbCredentials: {
        url: “path to the sqlite db on .wrangler folder”
    },
});

import { defineConfig } from ‘drizzle-kit’;

export default defineConfig({
    out: ‘./src/server/db/migrations’,
    schema: ‘./src/server/db/schema/index.ts’,
    dialect: ‘sqlite’,
    dbCredentials: {
        url: “path to the sqlite db on .wrangler folder”
    },
});

Is this feasible?
Also because to run in dev I can't use the wrangler cli but astro devastro dev.

Deltachaos•11/29/25, 10:04 AM

can someone explain to me the metrics here? Is it, that this single query caused 12.8k row reads for every execution, or that it caused 12.8k row reads total over 36k executions? If its the first case, why does it cause so many reads, when it should use the primary key here?

DDeltachaos can someone explain to me the metrics here? Is it, that this single query caused...

Florent•12/1/25, 10:58 AM

Hey, I'm not sure 100% sure, but I think it's the sum for all your queries based on the graphql documentation that is used to retrieve the number of rows read.
Having said that, the best way for you to check would be to explainexplain this specific query to find out what sqlite is doing under the hood https://sqlite.org/lang_explain.html.

PPeppineddu5 HI, I'm looking for a good way to distinguish between dev mode and production mo...

JustWayne•12/1/25, 4:44 PM

Here's how I do it - since the drizzle config is just a typescript file, I run some synchronous code to check for the existence of a

.dev.vars

.dev.vars

file and if I find one, I read it with an NPM package that can parse

.env

.env

files so I can get the development vars. During a production build the

.dev.vars

.dev.vars

file won't exist because it never goes into the repo. (With this tactic, I can have just the one standard

drizzle.config.ts

drizzle.config.ts

file and not have a separate local version of it.)

PPeppineddu5 HI, I'm looking for a good way to distinguish between dev mode and production mo...

JustWayne•12/1/25, 4:45 PM

I do the same thing for my Vite-based SPA, in the vite config file I read the

.dev.vars

.dev.vars

file using a

.env

.env

parser in order to get some details that I need related to Vite's devserver proxy config.

MManuel Ogomigo Oh this is a good idea 😳, I’ll work on that. Thank you so much

gruntlord6•12/1/25, 11:06 PM

That’s what I do as well with durable objects that do 500k+ rows each day, drop the table for those days on a Regular basis and keep the recent ones

gruntlord6•12/1/25, 11:06 PM

You can even have a worker cron handle that

Chandra Mohan Reddy V•12/2/25, 6:55 AM

Hello Cloudflare developers, I am facing issue with d1 export api. I've also posted details in https://community.cloudflare.com/t/d1-export-api-not-working/862800 Can some one please take a look at this?

Ggruntlord6 That’s what I do as well with durable objects that do 500k+ rows each day, drop ...

Manuel Ogomigo•12/2/25, 7:46 PM

Yeah really good idea. U've done that arleady and it's working fine!

Rafflesia•12/3/25, 6:58 PM

What does https://developers.cloudflare.com/api/resources/d1/subresources/database/methods/get/ do if the database already exists?

Cloudflare API | D1 › Database › Get D1 Database

Interact with Cloudflare's products and services via the Cloudflare API

RRafflesia What does https://developers.cloudflare.com/api/resources/d1/subresources/databa...

Hard@Work•12/3/25, 7:02 PM

Do you mean Create D1 Database?

Rafflesia•12/3/25, 7:03 PM

yeah

Rafflesia•12/3/25, 7:04 PM

apologies

RRafflesia yeah

Hard@Work•12/3/25, 7:06 PM

I would guess it would throw? Might be a good idea to test

RRafflesia What does https://developers.cloudflare.com/api/resources/d1/subresources/databa...

Florent•12/3/25, 7:07 PM

The API returns a 400 if the database name already exist

Rafflesia•12/3/25, 7:07 PM

alright thanks

Rafflesia•12/3/25, 7:07 PM

thanks

FFlorent The API returns a 400 if the database name already exist

Hard@Work•12/3/25, 7:08 PM

Thanks for the assist, Florent!

friss•12/4/25, 4:48 AM

So I am attempting to follow the "One D1 database per user" pattern since each user will uploading a sqlite database.

I have a pipeline where I process the sqlite DB, create a D1 db if one doesn't exist for the user, populate it and then bind it to my app worker.

The problem I'm running into is when I deploy my app worker the dynamic D1 bindings I added get removed since they aren't in the

wrangler.json

wrangler.json

.

Any ideas on how to handle that? I was thinking I could write a script to grab the current bindings before deploy but not exactly foolproof.

Ffriss So I am attempting to follow the "One D1 database per user" pattern since each u...

lambrospetrou•12/4/25, 11:47 AM

How many DBs are you expecting? If it's more than a few tens, low hundreds, I strongly suggest using Durable Objects directly instead. You can create millions of SQLite databases using the same DO Namespace binding, instead of having to add a binding for every D1 DB.

Other customers doing dynamic wrangler bindings with D1 handle it entirely through the API, due to the issues you faced with wrangler not being in sync.

Llambrospetrou How many DBs are you expecting? If it's more than a few tens, low hundreds, I st...

friss•12/4/25, 2:15 PM

Realistically less than 100 users is probably right.

I'll read up on durable objects and what that solution would look like to move to.

FFlorent There might be a way but it's not documented in our OpenAPI. I'll check with the...

Earl•12/4/25, 8:52 PM

I know you said you can't promise me a response from the team but on the faint chance that you only forgot to get back to me - were you able to get any information on this?

EEarl I know you said you can't promise me a response from the team but on the faint c...

lambrospetrou•12/4/25, 9:39 PM

Yeah, we will expose the bookmark/PITR operations in the REST API next week hopefully (or soon after) to have parity with wrangler. Need some cleanup work to complete first.

Earl•12/4/25, 9:41 PM

Thanks, that's great news!

Kevin•12/4/25, 10:19 PM

I wonder how the rows_read is calculated. I have a dataset with an index that will match only one row INDEX(a, b) that would return 2 rows read. I will drop that index and create UNIQUE INDEX(a, b) and that would return only 1 rows read.

Victor•12/5/25, 12:39 AM

I'd like to report that having 32+ (currently have 35) tables in the D1 studio, the scroll overflow stops and you can't see beyond that (but expanding dev tools shows the divs correctly there)

Josh M•12/5/25, 2:23 AM

I am seeing a really strange issue in D1 studio. When scrolling through my data, the scroll bar says that I am at the bottom when I am ~2 rows away from the actual end of the page. This makes it difficult to see that data because when I scroll to see it, as soon as I stop scrolling it will scroll back up and hide the data. The buttons to move between pages of data are also hidden. When I double click on one of those rows to edit a value, the page suddenly jumps down and I am able to see the bottom two rows normally, but all of the stuff right above the data in D1 studio disappear (tabs, query bar, add/remove row buttons, discard/commit buttons). This is happening to me on firefox. I have not tested any other browser

JJosh M I am seeing a really strange issue in D1 studio. When scrolling through my data,...

lambrospetrou•12/5/25, 9:04 AM

Thanks for the report, I will let someone on the team know and we will investigate.

Visal .In•12/5/25, 9:40 AM

Thanks for report. Fix is on the way.

JJosh M I am seeing a really strange issue in D1 studio. When scrolling through my data,...

welz•12/5/25, 10:35 AM

Having the same issue, also sometimes locks the scroll and can't fully scroll down - probably related.

Ggruntlord6 That’s what I do as well with durable objects that do 500k+ rows each day, drop ...

cloudkite•12/8/25, 4:39 PM

Is this actually faster? Curious since in other relational dbs there’s often a file per table so makes sense drop is quicker. However in SQLite since it’s one file wouldn’t it still need to find the rows?

Ccloudkite Is this actually faster? Curious since in other relational dbs there’s often a f...

gruntlord6•12/8/25, 8:16 PM

Yes, its significantly faster. SQlite still has more overhead in doing tons of individual deletes vs doing it for the entire table.

gruntlord6•12/8/25, 8:17 PM

Sqlite may be one file but it still has pages inside the file it needs to rearrange when you make writes or deletes