Please does anyone know why this:

SELECT to_tsvector('an'); 

returns nothing but

SELECT to_tsvector('nn');

or

SELECT to_tsvector('n');

or

SELECT to_tsvector('aa');

do?

I am testing this on PostgreSQL 13 running on SUPABASE.

Thanks

CodePudding user response：

Because "an" is a stop word in your current setup (probably English, the default).

From the documentation

The to_tsvector function internally calls a parser which breaks the document text into tokens and assigns a type to each token. For each token, a list of dictionaries (Section 12.6) is consulted, where the list can vary depending on the token type.

And (emphasis mine)...

Some words are recognized as stop words (Section 12.6.1), which causes them to be ignored since they occur too frequently to be useful in searching.