Change data capture (CDC) tools

CDC reads database changes (inserts, updates, deletes) as they happen and replicates them downstream. Log-based CDC (reading the WAL/binlog) is the cheapest at scale and the least invasive on the source. Trigger-based works on databases without log access but has write-load overhead. Query-based is a last resort. In 2026, Estuary Flow, Fivetran, Airbyte (Debezium-backed), and Debezium standalone are the realistic options.source - pulled 2026-06-21

Log-based vs trigger-based vs query-based

Log-based reads the database transaction log (Postgres logical replication, MySQL binlog, SQL Server CDC). It is incremental, low-overhead on the source, and captures deletes. Trigger-based fires a trigger on INSERT/UPDATE/DELETE to copy the change into a staging table. Query-based polls a timestamp column; it misses deletes and out-of-order updates, and it scales poorly.

Realistic finalist set

Estuary Flow

Streaming + CDC at the same $/GB rate

Fivetran

Premium tier covers log-based CDC for major DBs

Airbyte

Debezium-backed; Postgres and MySQL stable

Estuary vs Fivetran

CDC-first head-to-head

Written by Oliver Wakefield-Smith, Founder of Digital Signet. Independent reference, no vendor sponsorship.

Sources logged at /sources. Pricing-change history at /changelog. Last reviewed 2026-06-21.