Getting started

By the end of this page you will have run a reconciliation, seen it report a mismatch, and narrowed that mismatch down to the two rows responsible — all from your own machine. The walkthrough uses a self-contained dataset so you can follow it with no warehouse and no credentials. Point it at your own databases at the end is a two-line change.

Install the CLI

Docker
Build from source

docker pull europe-docker.pkg.dev/synq-cicd-public/synq-public/synq-recon:latest

Run it with your working directory mounted, so it can read your suite file:

docker run --rm -v "$PWD:/work" -w /work \
  europe-docker.pkg.dev/synq-cicd-public/synq-public/synq-recon:latest \
  check-config suite.yaml

The image runs DuckDB, which is what the walkthrough below uses so it needs no warehouse. If a type: duckdb connection fails with a driver error, your image predates DuckDB support — pull :latest.

If you have access to the monorepo:

cd synq-recon
go build -o synq-recon ./cmd/synq-recon

CGO must be enabled (it is by default) for DuckDB connections.

A public download channel for the binaries is on its way. Until it lands, the Docker image is the artifact available to everyone — get in touch if neither path works for you.

Check that it runs:

synq-recon --help

Authentication is only needed once you want to save suites to your workspace or run them on our backend. A purely local comparison needs no credentials at all.

synq-recon auth login
synq-recon auth whoami

auth whoami prints the workspace your credential resolves to. Get into the habit of reading that line — it is the only thing that decides which workspace a command writes to.

Describe what to compare

A suite is a YAML file holding the connections and the comparisons. Save this as quickstart.yaml:

quickstart.yaml

# yaml-language-server: $schema=https://schemas.synq.io/synq-recon/v1/config.schema.json

name: quickstart
title: Quickstart

connections:
  local:
    duckdb:
      database: ":memory:"

# Stands in for two real systems: an application database and the warehouse
# copy of it. The copy is missing one order and has the wrong amount on another.
setup:
  local:
    - |
      CREATE TABLE app_orders AS
      SELECT i AS order_id, 'CUST-' || (i % 7) AS customer_id, i * 10.0 AS amount
      FROM generate_series(1, 1000) AS t(i)
    - |
      CREATE TABLE warehouse_orders AS
      SELECT order_id, customer_id,
             CASE WHEN order_id = 617 THEN amount + 5 ELSE amount END AS amount
      FROM app_orders
      WHERE order_id <> 384

reconciliations:
  orders:
    title: Orders (application vs warehouse)
    source:
      connection: local
      table: app_orders
    target:
      connection: local
      table: warehouse_orders
    key_columns: [order_id]
    mode: row_checksum
    bisection:
      factor: 10
      threshold: 10

That first line points your editor at the published JSON schema, which gives you completion and inline validation for every field. Keep it at the top of every suite you write.

The bisection block is tuned small here so the drill-down has something to do on a thousand rows. On real tables the defaults are the right starting point.

Validate before you run

synq-recon check-config quickstart.yaml

Configuration Summary
=====================

Connections (1):
  - local (duckdb)

Reconciliations (1):
  - orders
    Source: local
    Target: local
    Key Column(s): order_id
    Mode: row_checksum
    Bisection: factor=10, threshold=10

Configuration check passed!

This costs nothing and touches no database. Add --db to also connect, run every query through the database’s planner, and report table sizes, indexes and a suggested key column:

synq-recon check-config quickstart.yaml --db

--db does not run the suite’s setup: SQL, so for this walkthrough it will report that app_orders does not exist. That is expected — the tables are created by setup when the comparison runs.

Compare

synq-recon run-check quickstart.yaml --no-report

Coalesce Quality Reconciliation - Quick Check
============================================

Reconciliation: Orders (application vs warehouse) (orders)
Mode: row_checksum
Duration: 6ms

             Source              Target
Row Count    1,000               999

Status: MISMATCH
  - Source has 1 more rows than target

Hint: Run 'synq-recon run-drill <config> --include orders' to locate differences.

Two queries — one per side — and you know the datasets disagree. If they had agreed, this would be the entire run.

The command exits 1. For a comparison, a non-zero exit means “differences found”, which is a result rather than a failure. Exit codes has the full list.

--no-report keeps the run entirely local. Without it, a run reports its results to your workspace whenever it can find a credential, so they show up in the app alongside backend runs.

Locate the difference

synq-recon run quickstart.yaml --auto-drill --no-report

Depth 0: Segment [*, *)
  Source: 1,000 rows, checksum: -2052783606565609
  Target: 999 rows, checksum: -2210053578859533
  Status: MISMATCH -> drilling down (20/1,000 rows in mismatched segments)
  Depth 1: Segment [301, 401)
    Source: 100 rows, checksum: -167029730887454
    Target: 99 rows, checksum: -295596598382435
    Status: MISMATCH -> drilling down (10/100 rows in mismatched segments)
    Depth 2: Segment [381, 391)
      Source: 10 rows, checksum: 330886401684630
      Target: 9 rows, checksum: 202319534189649
      Status: MISMATCH (leaf: threshold_reached)
  Depth 1: Segment [601, 701)
    Source: 100 rows, checksum: -683539572079355
    Target: 100 rows, checksum: -712242676878298
    Status: MISMATCH -> drilling down (10/100 rows in mismatched segments)
    Depth 2: Segment [611, 621)
      Source: 10 rows, checksum: -381158226855223
      Target: 10 rows, checksum: -409861331654166
      Status: MISMATCH (leaf: threshold_reached)

Summary
-------
Segments processed: 33
Mismatch leaves: 2
Max depth reached: 2
Duration: 26ms

Read that from the top. The whole dataset disagrees, so it is split into ten segments; eight of them match on the first comparison and are never looked at again. The two that differ get split again, and the run stops with two ten-row windows to inspect. Notice the shape of each finding. The segment around order 384 has one fewer row on the target — a missing row. The segment around order 617 has the same count but a different checksum — a value changed. You have not read a single row value yet.

Thirty-three queries to find two bad rows in a thousand. The saving grows with the table: the number of comparisons scales with the logarithm of the row count, not the row count. That is the whole point of the drill-down.

Get the rows

Every mismatch leaf comes with ready-to-run SQL for both sides:

synq-recon run-drill quickstart.yaml --no-report -o json 2>/dev/null \
  | jq -r '.investigation_queries[] | .source_query, .target_query, "--"'

Run those against the two databases and you are looking at the rows themselves. This is the point at which row values enter the picture — on your terms, in your SQL client, for ten rows rather than a million.

Redirect logs with 2>/dev/null, never 2>&1. Logs go to stderr and results to stdout; merging them makes -o json unparseable.

Point it at your own databases

Swap the connections: block for the real thing, drop the setup: block, and name your tables. Nothing else changes:

suite.yaml

connections:
  app:
    postgres:
      host: db.internal
      port: 5432
      database: payments
      username: ${PG_USER}
      password: ${PG_PASSWORD}
  warehouse:
    snowflake:
      account: myorg.us-east-1
      warehouse: COMPUTE_WH
      role: ANALYST
      username: ${SF_USER}
      password: ${SF_PASSWORD}
      databases: [ANALYTICS]

reconciliations:
  orders:
    title: Orders (application vs warehouse)
    source:
      connection: app
      table: public.orders
    target:
      connection: warehouse
      table: ANALYTICS.PUBLIC.ORDERS
    key_columns: [order_id]
    mode: row_checksum

Then run the same four commands. Two things to do before you trust the result:

Keep the credentials out of the file. Move the connections: block to a git-ignored .connections.yaml — the CLI picks it up automatically. See keep credentials out of the suite.
Run check-config --db. It confirms every connection and query, and warns if your key column is not indexed — which is the difference between a drill that takes seconds and one that takes minutes.

Next steps

Authoring suites

Datasets, column selection, key columns, and the validation loop in full.

Time windows and cutoffs

Comparing two live systems? Read this before you trust a mismatch.

Workspace suites

Save the suite, run it on our backend, put it on a schedule.

CLI reference

Every command, argument and flag, generated from the CLI itself.

Get Started

Alerts

Monitors

Monitors Types

Reconciliations

Data Products

Scout AI

Ownership

Incidents

Analytics

Lineage

BI Integrations

Data Warehouse Integrations

Transactional databases

Code Integrations

dbt Integrations

SQLMesh Integrations

Coalesce Integrations

Orchestration Tool Integrations

Alerting Integrations

Catalogs

Google Cloud Integrations

Admin

Security

Support

Developer API

Install the CLI

Describe what to compare

Validate before you run

Compare

Locate the difference

Get the rows

Point it at your own databases

Next steps

Authoring suites

Time windows and cutoffs

Workspace suites

CLI reference

​Install the CLI

​Sign in

​Describe what to compare

​Validate before you run

​Compare

​Locate the difference

​Get the rows

​Point it at your own databases

​Next steps

Authoring suites

Time windows and cutoffs

Workspace suites

CLI reference

Install the CLI

Sign in

Describe what to compare

Validate before you run

Compare

Locate the difference

Get the rows

Point it at your own databases

Next steps