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Line-delimited JSON New

Query a JSONL Folder with SQL — in Excel, Google Sheets, AI and REST

Query folders of JSONL / NDJSON event logs as tables. Nested fields are flattened into real columns you can filter on, without anyone writing a parser first.

Start free 13 destinations JSONL Folder guide

One connection, every surface

Where your JSONL Folder data can go

JSONL Folder many files → one live table each
Federated queries + any other connector · one SQL across sources · every plan
Network Agent
  • 1 outbound connection
  • 0 inbound ports
  • read-only · files stay put

runs on

Query Streams turns a folder of JSONL / NDJSON event logs into live SQL tables readable from Microsoft Excel, Google Sheets, AI assistants over MCP, the REST API and Power BI. Nested objects are flattened into real columns you can put in a WHERE clause, and the self-hosted agent reads each file in full rather than sampling the top, so a field that only shows up in the last hundred lines is still found. Logs stay on your machine; only query results leave the network.

One of 9 File Set drivers on one folder engine — the inventory tables, change trail and refusal rules under features are shared by the family JSONL Folder File System CSV Folder Parquet Folder Excel Folder SQLite Folder Multi-record CSV Machine Logs Web Server Logs

  1. For your team, vendors and partners

  2. JSONL Folder to Excel Microsoft Excel · Excel add-in

    Pull live JSONL Folder results straight into a worksheet and refresh them on demand — desktop Excel, Excel Online, Microsoft 365.

    How Excel works

  3. JSONL Folder to Google Sheets Sheets add-on

    Run a saved JSONL Folder query from the sidebar and drop the rows into the sheet. Shared collaborators can refresh it themselves.

    How Google Sheets works

  4. Ask Nova about JSONL Folder Nova AI · text to SQL

    Ask a question in plain English. Nova already knows your JSONL Folder tables, writes and runs the SQL, explains the answer and charts it — no query to write, no credentials to hand over.

    How Nova works

  5. JSONL Folder to Data Viewer result sharing · team, vendors, partners · phone, tablet, desktop

    Share a live JSONL Folder result with anyone — a colleague, a vendor, a partner — as a bookmarkable grid that re-runs fresh when opened, on a phone, a tablet or a desktop. They see the results, never the SQL or the files.

    How the Data Viewer works
  6. For apps and systems

  7. JSONL Folder REST API HTTP endpoint

    Publish a JSONL Folder query as an authenticated JSON endpoint any application can call, with an OpenAPI 3.1 spec and ready-made Postman, Insomnia and Hoppscotch collections. No database port is opened.

    How REST API works

  8. JSONL Folder to Power BI Power Query M

    Paste the generated Power Query M into the Power BI Advanced Editor and the report reads live JSONL Folder results over HTTPS — no ODBC driver, no database port opened.

    How Power BI works

  9. JSONL Folder to Airtable Automation platform

    Sync JSONL Folder rows into an Airtable base on a schedule, or fetch them inside an Airtable automation script.

    How Airtable works

  10. JSONL Folder to Baserow Automation platform

    Feed a Baserow table from JSONL Folder over the REST endpoint — self-hosted or Baserow cloud.

    How Baserow works

  11. JSONL Folder to SeaTable Automation platform

    Keep a SeaTable base current with JSONL Folder data without exporting a file or exposing the database.

    How SeaTable works

  12. JSONL Folder to Smartsheet Automation platform

    Push JSONL Folder results into a Smartsheet grid so plans and reports read from the source system, not last week's export.

    How Smartsheet works

  13. JSONL Folder to Anvil Anvil Works · App platform

    Back an Anvil Python app with JSONL Folder through the REST endpoint instead of embedding database credentials in the app.

    How Anvil works
  14. For AI tools

  15. JSONL Folder MCP server Claude, Cursor and MCP clients

    Give an AI assistant read-only access to JSONL Folder with the schema it needs to write correct SQL — no credentials in the chat.

    How MCP works
  16. Delivered to people

  17. JSONL Folder alerts and reports Slack · Discord · Email · Webhook

    Put a JSONL Folder query on a schedule and have the rows delivered to Slack, Discord, email or a signed webhook — or hold the message until a row count, threshold or percentage change crosses the line you set.

    How alerts and reports work

How it works

5 steps, no inbound firewall change

01

Install the Network Agent where it can see the folder — application logs, webhook archives, event exports, one JSON object per line.

02

Point the connector at it; every .jsonl file is matched.

03

The agent reads the files in full rather than sampling the top, so a field that only shows up in the last hundred lines is still found.

04

Nested objects are flattened into columns two levels deep by default, up to eight. fulfillment.site.region becomes a column you can put in a WHERE clause. Arrays and anything deeper stay as JSON you can still query.

05

Every row carries a _source_file column, so a day's file, or the whole archive, is one query away.

Feature deep-dive

What JSONL Folder gives you

Built for messy event data

  • Whole files are read, not sampled — a rare field is not missed because it did not appear early.
  • Deeper structures are kept as JSON rather than dropped, so nothing is silently lost.
  • A field that starts appearing later is treated as a change and reported, not quietly ignored.
  • If the folder holds genuinely different event shapes, per-layout mode gives each shape its own table, up to 25.
-- Events per day, straight out of the log folder
SELECT   _source_file AS day, status, COUNT(*) AS events
FROM     data
GROUP BY day, status
ORDER BY day

Strict, one line at a time

A single malformed line holds the whole file back rather than loading a half-truth, and the file is named in files_events. Fix it or exclude it and the next sync picks it up — you never end up reconciling a total that is quietly missing three rows.

Shared by the whole File Set family

Every folder connector also gives you

  • files_current — a live inventory: every file the connector can see right now, with its path, size and modified date.
  • files_events — the audit trail: what appeared, what changed, what vanished, and anything held back, with the filename and the reason.
  • directories and volumes — per-folder totals, daily growth history, and how much room is left on the drive.
  • Only files that actually changed are re-read on each sync, so a folder of 50,000 files is not re-parsed because one new export landed.

Good to know

  • Read-only, enforced — one statement at a time, SELECT and friends only. Your files are never written, moved or renamed.
  • Nothing is uploaded — the data is cached, encrypted, on your own machine beside the agent. Only the result of a query leaves your network.
  • Sensible defaults — up to 250,000 files, 16 folders deep, 512 MB per file, all adjustable. Recycle bins, .git and node_modules are always skipped.
  • The SQL dialect is DuckDB — the same SQL you would write against any other connector.

Cross-source SQL

Join JSONL Folder to the rest of your data

A folder of files is a set of SQL tables like any other, so one statement can join it to a database and an API at once. Each source runs only the part it can, streams the result back, and the join happens centrally — the sources never talk to each other and nothing is copied anywhere.

3 connections · 3 agents

JSONL Folder Line-delimited JSON
PostgreSQL Relational engine
Stripe Payments & billing

One statement

-- nothing copied, nothing merged, nothing scheduled
SELECT   c.region, COUNT(*) AS orders, SUM(i.amount_due) AS invoiced
FROM     event_logs.fileset.data1 f
JOIN     pg_crm.public.customers2 c ON c.id = f.customer_id
JOIN     billing.stripe.invoices3 i ON i.customer = c.stripe_id
GROUP BY c.region
ORDER BY invoiced DESC;

The three parts are connection, schema and table — and the connection name is whatever you called it. Illustrative columns; your tables will be your tables. Read-only applies to every piece: SELECT, WITH and EXPLAIN only, with a ceiling on how much any one source may hand over for a single query. How federated queries work

Connection details

What JSONL Folder needs

Folder
One or more roots holding .jsonl files, subfolders included — application logs, webhook archives, event exports, one JSON object per line
Schema
Read from whole files rather than a sample, so a field that only appears late in a large log is still found
Nesting
Objects are flattened into columns two levels deep by default and up to eight — fulfillment.site.region becomes a column you can filter on
Deeper structures
Arrays and anything below the flatten depth stay queryable as JSON rather than being dropped
Strictness
One malformed line holds its whole file back rather than loading a half-truth, and the file is named in files_events
Per-layout mode
If the folder genuinely holds different event shapes, each shape can get its own table — up to 25
Limits
Up to 250,000 files, 16 folder levels deep, 512 MB per file — all adjustable
Credentials
None — there is no server; the agent reads the logs in place
SQL dialect
DuckDB — standard SQL, nothing log-specific to learn

There is no database server in this picture. The agent reads the .jsonl files where they already live, caches the rows in an encrypted DuckDB store on the same machine, and re-reads only files that actually changed — a year of daily log files is not re-parsed because today's landed. Nothing is uploaded to Query Streams; the only thing that ever leaves your network is the result of a query.

Flatten depth is part of the pinned schema, not a per-query setting. That is deliberate: fulfillment.site.region has to mean the same column on Monday that it meant on Friday, or every saved query and every scheduled refresh quietly changes meaning underneath you. Raising the depth later is a schema change, and it is handled and reported as one.

Vendor documentation: jsonlines.org

FAQ

Questions about JSONL Folder

Which tools can read JSONL Folder data through Query Streams?

All of them, from one connection: Excel, Google Sheets, MCP, REST API, Airtable, Baserow, SeaTable, Smartsheet, Anvil, Power BI, scheduled alerts and reports. Connect the folder once and every surface reads the same read-only connection — there is no per-tool setup and no second copy of the data.

Do my files get uploaded to Query Streams?

No. The Network Agent reads the files in place and caches rows in an encrypted store on the same machine. The files themselves never leave your network — only the result rows of a query do, over a single outbound encrypted connection with no inbound firewall port.

Can Query Streams change, move or rename my files?

No. Files are opened strictly read-only and are never written, moved or renamed. Queries are enforced read-only at the point of execution — one statement at a time, SELECT and friends only.

What does Query Streams need to connect to JSONL Folder?

A folder path the agent machine can see — no server, no credentials, no drivers to install. Folder: One or more roots holding .jsonl files, subfolders included — application logs, webhook archives, event exports, one JSON object per line. Schema: Read from whole files rather than a sample, so a field that only appears late in a large log is still found. Nesting: Objects are flattened into columns two levels deep by default and up to eight — fulfillment.site.region becomes a column you can filter on. Deeper structures: Arrays and anything below the flatten depth stay queryable as JSON rather than being dropped.

Can I join a folder of files to a database in the same query?

Yes — that is a federated query. One statement can reference JSONL Folder and your other connections at once, written as connection.schema.table. Each source runs only the part it can and streams the result back; the join happens centrally, so the sources never connect to each other and nothing is copied or scheduled. Read-only applies to every piece — SELECT, WITH and EXPLAIN only — and there is a ceiling on how much any one source may hand over for a single query. Federated queries are a plan feature; the federated queries page carries the current source and size limits.

Put JSONL Folder where the work happens

Install the agent, point it at your folder, and pick a destination.

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Read-only Outbound only Credentials stay on the agent