Re: BUG #14521: pg_attribute.attndims = 0 for array column

Krzysztof Heim <krzysztof(dot)heim(at)gmail(dot)com> writes:
> If I may ask, what is then the best way of checking if column is array.

The standard way for C code is to use this macro from lsyscache.h:

#define type_is_array(typid) (get_element_type(typid) != InvalidOid)

or depending on what you're doing, you might want these semantics:

/* type_is_array_domain accepts both plain arrays and domains over arrays */
#define type_is_array_domain(typid) (get_base_element_type(typid) != InvalidOid)

or then again, you might just want to check if the type has nonzero
typelem --- that would be the appropriate thing if you want to see
whether the type is subscriptable.

regards, tom lane