Postgresql - "IN empty array" syntax

Question

I create programmatically sql queries to Postgresql like this:

SELECT * FROM table WHERE column IN (1, 2, 3);
SELECT * FROM table WHERE column IN (1);
SELECT * FROM table WHERE column IN ();

The last query generates a syntax error. How should I handle this special case and write an empty array here?

Answer 1

Internally,

col IN (1, 2, 3)

is converted to

col = ANY (ARRAY[1,2,3]::integer[])

That syntax will also work for empty arrays:

col = ANY (ARRAY[]::integer[])