Kris Jurka <books@ejurka.com> writes:
> Multi-dimensional array information is not stored. Every array type may
> be any number of dimensions. The precision information is not available
> in the information_schema, but it is available in the system catalog
> tables. See pg_attribute.atttypmod, but it does require some decoding.

Rather than embedding knowledge of typmod encoding in client-side code,
may I suggest using the format_type function? For example

select format_type(atttypid, atttypmod) from pg_attribute where
attrelid = 'my_table'::regclass and attname = 'my_column';

This will give you back something reasonably standardized, like
"character varying(42)[]". You'll still need a bit of logic to
extract what you want, but it seems much less likely to break.

regards, tom lane

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