Ingest your data
into ClickHouse from day one

Backfill historical data, keep CDC in sync, handle schema changes, normalize messy data, and keep ClickHouse queries correct.

ClickHouse Ingestion Problems

Most ClickHouse projects break
in the first 30 days

ClickHouse queries are fast but getting correct data into ClickHouse is the hard part. Most teams face one or more of these issues when ingesting data to ClickHouse:

Historical backfills are painful

You need old PostgreSQL, MySQL, or MongoDB data in ClickHouse before your analytics are useful. But historical imports usually break when live updates start.

Keeping ClickHouse continuously synced from Postgres WAL, MySQL binlog, MongoDB, or Debezium quickly becomes messy. Teams end up maintaining custom glue code.

CDC becomes fragile

Historical imports and CDC running together create race conditions.

Older rows overwrite newer state. Your analytics become inconsistent.

Backfills overwrite live updates

A new column appears. JSON changes. Nullable types drift. Suddenly, ingestion fails.

Schema changes break ingestion

Strings instead of Int32. Broken timestamps. Mixed date formats. Nested JSON. ClickHouse rejects rows or silently stores incorrect data.

Data arrives in the wrong format

OTEL, CDC, events, and billing systems. You want one correct table in ClickHouse. Instead, pipelines become messy.

Data comes from multiple systems

Duplicates arrive. ReplacingMergeTree gets confusing. FINAL becomes expensive. You no longer trust the data.

Queries are not immediately correct

Duplicates arrive. ReplacingMergeTree gets confusing. FINAL becomes expensive. You no longer trust the data.

ClickHouse Ingestion, Solved

Built specifically to solve ClickHouse
ingestion pains

GlassFlow sits between your sources and ClickHouse. Deduplication, filtering and data transformations are resolved upstream, not patched downstream.

01

Safe Historical Backfills

GlassFlow separates initial historical imports from live CDC and keeps both ordered before data reaches ClickHouse. Instead of blindly writing data to ClickHouse, GlassFlow tracks event timestamps and primary keys to ensure newer updates will not overwrite historical records.

02

Built-in CDC for PostgreSQL, MySQL, and MongoDB

GlassFlow reads database changes directly from:

  • PostgreSQL: WAL

  • MySQL: binlog

  • MongoDB CDC > Debezium

  • Kafka topics

  • custom CDC streams

For teams already using Debezium: GlassFlow consumes CDC events and prepares them for ClickHouse.

For simpler teams: GlassFlow can set up CDC internally without requiring Kafka. Instead of building custom consumers, GlassFlow turns change events into query-ready ClickHouse data.

03

Safe historical & live sync for ClickHouse

GlassFlow tracks entering and state updates before ingestion.

Using timestamps, primary keys, and configurable conflict rules, GlassFlow ensures only the newest version of a record reaches ClickHouse. Configurable for long-time windows.

Instead of relying on expensive FINALs queries later, correctness is enforced before ingestion.

04

Schema evolution built in

GlassFlow continuously observes incoming schemas and adapts pipelines automatically.Instead of failing ingestion, GlassFlow keeps multiple schema versions flowing safely while adapting ClickHouse in the background.

05

Data Normalization

GlassFlow transforms messy operational data before it reaches ClickHouse. Teams can:

  • correct data  types

  • normalize timestamps

  • extract values from strings

  • flatten JSON

  • standardize formats

06

Multiple Connectors

GlassFlow manages operational data before it reaches ClickHouse. No matter if you use OTEL, PostgreSQL, Kafka, etc. Manage all your ClickHouse connectors in one place. See all integrations

07

Deduplication before ClickHouse

GlassFlow deduplicates records before ingestion using configurable windows and primary keys.

Instead of sending every duplicate event into ClickHouse:

  • GlassFlow only forwards the correct latest version.

  • This keeps dashboards and queries correct immediately.

  • Without waiting for background merges.

  • Without expensive FINAL queries.

08

Optimized ingestion for ClickHouse

Fast ingestion is not only about throughput. It is about writing data in the way ClickHouse expects.

GlassFlow automatically optimizes its ingestion logic for ClickHouse. Instead of sending tiny inefficient writes or overwhelming clusters with bad ingestion patterns, GlassFlow continuously batches and flushes data using ClickHouse-friendly block sizes.


This improves:

  • ingestion performance

  • query performance

  • storage efficiency

  • cluster stability

Without manual tuning.

Why GlassFlow

Purposely-built for
ClickHouse Ingestion

General-purpose ETL tools are great at moving data.

ClickHouse ingestion is different.

Generic ETLs

Fix after data arrived

Data arrives in the right shape

Generic ETL tools are built for broad data movement

But ClickHouse introduces challenges that general-purpose pipelines often struggle with, like schema evolution, wrong data types, duplicatesCDC, dumb ingestion logic, and more.

ClickHouse Ingestion at Scale

Start simple.
Scale when you need it.

10x growth of your data? Nothing to worry about. Start with GBs and end up with TBs of data ingested into ClickHouse per day. GlassFlow is built to support you through your entire ClickHouse growth journey.

Horizontal scaling

High throughput ingestion

Low latency

Run GlassFlow your way

Start in minutes or deploy inside your own infrastructure

BYOC - Managed Service

GlassFlow runs in your cloud account

Data stays within glassflow.app/cloud

We manage upgrades, infrastructure, reliability and operations while your data stays in your infrastructure.

Fast setup

Low operational overhead

Production reliability

Full control of data residency

Self-Hosted

GlassFlow runs entirely in your infra

Deploy in Kubernetes in your preferred environment with full control over networking, security, and scaling.


Full infrastracture control

Private environments

Compliance requirements

Custom deployment flexibility

Need prod guarantees?

  • 24/7/365 support

  • SLAs

  • Slack/Teams support

  • Personalized onboarding and training

  • Implementation engineers

Get correct data into ClickHouse from day one

Stop building custom CDC glue code and fighting broken ingestion.

Get correct data into ClickHouse from day one

Stop building custom CDC glue code and fighting broken ingestion.

Get correct data into ClickHouse from day one

Stop building custom CDC glue code and fighting broken ingestion.