PostgreSQL to BigQuery
real-time replication
TwinCommit replicates PostgreSQL to Google BigQuery in real time by reading the PostgreSQL transaction log and applying every committed change exactly once and in commit order. Use it to feed BigQuery with live PostgreSQL data for analytics, AI and reporting, with no triggers or capture tables on the source.
PostgreSQL
log reader
commit-ordered · exactly-once
BigQuery
native writer
How capture works on PostgreSQL
TwinCommit uses a logical replication slot with the built-in pgoutput plugin, so there is nothing to install on the server.
Prerequisites
- ✓wal_level = logical
- ✓REPLICATION privilege
- ✓Primary key or REPLICA IDENTITY FULL
How apply works on BigQuery
Changes stream through the BigQuery Storage Write API into staging tables and are applied with MERGE on a configurable interval, so deletes and updates are reflected exactly.
Requirements
- ✓A service account with BigQuery Data Editor and Job User
- ✓A dataset for staging tables
- ✓Primary keys declared on target tables (recommended)
Setup
Set up PostgreSQL → BigQuery in four steps
- 1
Prepare PostgreSQL
Run twincommit check. It verifies wal_level = logical and the other prerequisites, and prints the exact fix for anything missing.
- 2
Point at BigQuery
Add a target block for BigQuery. TwinCommit can generate target DDL with twincommit ddl -apply.
- 3
Snapshot
twincommit snapshot copies each table under a brief share lock and records the exact log position.
- 4
Stream
twincommit run streams every committed change from that position, exactly once and in commit order.
source:
type: postgres
dsn: ${SOURCE_DSN}
slot: twincommit
target:
type: bigquery
project: acme-analytics
dataset: replica
credentials_file: /secrets/bq.json
tables:
- source: SALES.ORDERS
- source: SALES.ORDER_LINES
exclude_columns: [INTERNAL_NOTES]PostgreSQL to BigQuery replication FAQ
How does TwinCommit replicate PostgreSQL to BigQuery?
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TwinCommit reads changes from the PostgreSQL transaction log, buffers them per transaction, and applies each committed transaction to BigQuery in commit order. Changes stream through the BigQuery Storage Write API into staging tables and are applied with MERGE on a configurable interval, so deletes and updates are reflected exactly.
Does PostgreSQL to BigQuery replication need triggers or capture tables?
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No. TwinCommit reads the PostgreSQL log directly and creates no objects in the source database.
Is PostgreSQL to BigQuery replication exactly-once?
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Yes. TwinCommit commits its checkpoint in the same BigQuery transaction as the data, so a crash or restart never loses or duplicates a transaction.
What PostgreSQL versions are supported?
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PostgreSQL 13–18 · Amazon RDS and Aurora · Azure Flexible Server · Cloud SQL · AlloyDB.
Stream PostgreSQL to BigQuery today.
Download the free Developer edition, or have one of our replication engineers walk you through a migration plan.