Bug with implicit type casting

[michailtoksovo]

create table usertable (id bigserial primary key, value text not null);
-- CREATE TABLE

update usertable set value = 'row' || id;
-- UPDATE 0

select create_distributed_table('usertable', 'id', shard_count := 2);
update usertable set value = 'row' || id;
-- ERROR:  STABLE functions used in UPDATE queries cannot be called with column references

update usertable set value = 'row' || id::text;
-- UPDATE 0

select citus_version();
-- Citus 12.1.1 on x86_64-pc-linux-gnu

[michailtoksovo]

Update 2025-06-19

Citus always returns an error if you use the function concat():

create table usertable (id bigserial primary key, value text not null);
-- CREATE TABLE

-- PostgreSQL 16.8
update usertable set value = 'row' || id;
-- ✔️ UPDATE 0

-- and PostgreSQL 16.8 with Citus 12.1.1 
select create_distributed_table('usertable', 'id', shard_count := 2);

update usertable set value = concat('row', id);
-- ❌ ERROR:  STABLE functions used in UPDATE queries cannot be called with column references

update usertable set value = concat ('row', id::text);
-- ❌ ERROR:  STABLE functions used in UPDATE queries cannot be called with column references

[ihalatci]

Excerpt from the link below by @JelteF
"...The CONCAT function is stable instead of immutable, this is often the case for functions that take any/anyelement as an argument....Instead you should be able to use the string concatenation operator ||, but be sure to cast all items to text, otherwise you might get the same problem with it using a anyelement version of the || operator."
https://stackoverflow.com/questions/71132925/postgres-citus-immutable-date-conversion