Citus into Apache Arrow through ADBC, using psqlodbc 16 — distributed tables included (adbcBridge 0.1.0)

[singhpratech]

adbcBridge is a small Apache-2.0 ADBC driver written in C11 that loads an ODBC driver and exposes it through the Arrow ADBC C ABI: block-cursor reads straight into Arrow record batches, bulk ingest, metadata, partitioned parallel reads. I ran Citus through it as one of 46 databases in a single compatibility workload and wanted to share the entry here.

What was verified (Citus 14.1 on PostgreSQL 18; driver: psqlodbc 16):

• Linux: PASS
• macOS arm64: PASS (PostgreSQL wire 18.4; amd64 emulated)
• Windows x64: PASS (PostgreSQL 18.4 + Citus 14.1.0; distributed-table steps included)

What the compatibility entry records: no quirks. Citus is an extension on stock PostgreSQL, so the array-ingest form applies and is used, distributed tables included — the entry also ingests into and reads back a create_distributed_table() hash-distributed table. A fresh single node needs no registration: create_distributed_table() registers the coordinator itself with shouldhaveshards on; if the coordinator was registered with citus_set_coordinator_host() alone, shouldhaveshards has to be set too, or create_distributed_table() fails with replication_factor (1) exceeds number of worker nodes (0) (Citus 14.1.0 on PostgreSQL 18.4, citusdata/citus:latest). Measured: ingest 107k rows/s (array binding), fetch 1.86M rows/s. Full entry: docs/COMPATIBILITY.md.

The postgresql ADBC driver may also work with Citus over its wire protocol; this path goes through psqlodbc and records exactly what it needed, so it is a second, documented route rather than a replacement.

Trying it (Python; Rust, Go, Java, C# and R are on the docs site):

pip install adbcbridge

import adbcbridge
with adbcbridge.connect(uri="Driver=PostgreSQL Unicode;Server=127.0.0.1;Port=5432;Database=postgres;Uid=postgres;Pwd=...") as conn:
    with conn.cursor() as cur:
        cur.execute("SELECT ...")
        table = cur.fetch_arrow_table()   # a pyarrow.Table

Links: repository · docs · upstream notes · PyPI

It is a 0.1.0. If the entry says something wrong about Citus, or you run a version or driver I didn't, an issue on the repository with the details is the most useful thing you could send.