db2fce

db2fce : DB2 compatibility functions, types, operators, and SYSIBM.SYSDUMMY1 for PostgreSQL.

Overview

Packages

Source

pig build pkg db2fce;		# build rpm/deb

Install

Make sure PGDG and PIGSTY repo available:

pig repo add pgsql -u   # add both repo and update cache

Install this extension with pig:

pig install db2fce;		# install via package name, for the active PG version

pig install db2fce -v 18;   # install for PG 18
pig install db2fce -v 17;   # install for PG 17
pig install db2fce -v 16;   # install for PG 16
pig install db2fce -v 15;   # install for PG 15
pig install db2fce -v 14;   # install for PG 14

Create this extension with:

CREATE EXTENSION db2fce CASCADE; -- requires plpgsql

Usage

Sources: README, SQL objects, control file

db2fce provides a DB2 compatibility environment for PostgreSQL. It creates DB2-style functions, types, operators, and the SYSIBM.SYSDUMMY1 compatibility view so SQL originally written for IBM Db2 can be adapted with fewer changes.

Enable

CREATE EXTENSION db2fce;

SET search_path = db2, sysibm, public;

The extension creates most compatibility objects in the db2 schema and creates sysibm.sysdummy1 for DB2 queries that expect a dummy single-row table.

SELECT * FROM sysibm.sysdummy1;

Compatibility Functions

The db2 schema includes date/time helpers such as microsecond, second, minute, hour, day, month, year, days, months_between, date, time, and timestamp_format.

String and conversion helpers include locate, translate, lcase, upper, lower, strip, char, integer, int, double, decimal, dec, hex, round, digits, and value.

Operators

The SQL layer also defines DB2-style operators such as ^= for inequality and !! for concatenation across several data types.

SELECT db2.int('42');
SELECT db2.days(current_date);
SELECT 'db' !! '2';

Notes

Adding db2 to search_path lets many DB2 function calls work without schema qualification. Some names that conflict with PostgreSQL syntax or built-in behavior may still need explicit db2. qualification.