← All databases

Actian Ingres into Apache Arrow with ADBC

Actian Ingres 10.1 (open-source edition), read and written through adbcBridge — the ADBC driver that loads the database's ODBC driver — verified on Linux. Everything below is the compatibility matrix's record for this row.

Status

Driver and connection string

ODBC driver

Ingres ODBC (libiiodbcdriver.1.so, ships with the installation)

Wire

native ODBC

adbcBridge

0.1.1 (release)

The connection string the matrix used, as the connection strings reference records it (Databases with their own native protocol and ODBC driver); {drv} is the driver library or its name from odbcinst.ini, and the host, port and credentials are the test server's.

Driver={drv};Server=adbcing;Database=adbc;UID=ingres;PWD=adbc;ServerType=INGRES;

Python

import adbcbridge

# {drv}: the ODBC driver library (path), or its name from odbcinst.ini
conn = adbcbridge.connect(uri="Driver={drv};Server=adbcing;Database=adbc;UID=ingres;PWD=adbc;ServerType=INGRES;")
with conn.cursor() as cur:
    cur.execute("SELECT * FROM my_table")
    table = cur.fetch_arrow_table()      # pyarrow.Table

Polars and pandas

import polars as pl, pandas as pd

df = pl.read_database("SELECT * FROM my_table", connection=conn)   # Polars, Arrow-native
pdf = pd.read_sql("SELECT * FROM my_table", conn)                   # pandas 2.2+, ADBC connection

pip install adbcbridge brings the driver library; the Actian Ingres ODBC driver is installed the way its vendor documents, then named in Driver=. Rust, Go, C# and Java use the same connection string through their ADBC driver managers — see the docs.

What the matrix recorded

Ingres' own driver over Ingres/Net on 21064. It cannot be used through unixODBC as it stands: its wide entry points take a four-byte SQLWCHAR (the platform wchar_t) while unixODBC's is two, and unixODBC picks a driver's Unicode path purely by finding SQLConnectW in it, so the connection string arrives as its first character and the connect fails 08004 / 786744 E_GC0138_GCN_NO_SERVER — an empty vnode and database, leaving just the /INGRES server class.

What this stack needed

• The same call with a UTF-32 string connects, which is the proof of the width.
• Its *narrow* entry points are correct and complete, so the entry loads it behind a generated ANSI-only forwarding library (fixtures/ingres_ansi_shim.c, 72 one-jump stubs) and unixODBC does the UCS-2 conversion itself.
• A second driver bug sets the shape of the connection string: Driver= is strcpy'd into a 32-byte buffer, so any real path aborts the process outright (* buffer overflow detected *, __strcpy_chk under ConDriverInfo) — the entry registers the shim in odbcinst.ini and names it Driver=Ingres.
• Two bridge quirks then carry it: 32-bit SQLLEN (as for the Db2 clidriver — a NULL column otherwise reads back as the row before it, a NULL FLOAT8 as 1e-323), and no usable SQL_C_WCHAR parameters (each 16-bit unit is treated as a code point, so a surrogate pair is rejected: 5000B, *Unicode code point 0000D83D cannot be mapped to local character set* — UTF-8 narrow path instead, as for Firebird, Virtuoso and Informix).
• Server side: createdb -n (a Unicode-enabled database, without which a VARCHAR cannot hold the emoji and NVARCHAR cannot be created at all), date_alias = ansidate before the DBMS starts (on the default, ANSIDATE is created as Ingres' own date-*and-time* INGRESDATE, whose NULL comes back as the year-0 empty date), and an Ingres user for the local account the client runs as — the vnode login authenticates the connection while the session still runs as the caller's OS user (E_US18FF).
• Ingres SQL has no multi-row VALUES at all (Syntax error on ','), so bulk ingest falls back to parameter arrays on its own.
• Actian's own actian/ingres:ii12.1.0 image refuses to start without a commercial license.xml, so the server is the GPL ingres-10.1.0-00-NPTL build baked into the community image iidbdb/ingres; ingest 1.1k rows/s (1.3k array), fetch 393k rows/s

Read next

• The Ingres ODBC client kills any Java process that loads it
• A NULL column that reads back as the previous row's value
• The process dies with SIGABRT on the first SQL error, and it is the manager