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NpgSQL Throwing Exception

Im currently working on a .Net application that has a PostgreSQL backend. Im using NpgSQL to connect the two. When I try to do simple data retrieval, NpgSQL returns the following error:

42601: syntax error at or near "get_all_reviews"

PostgreSQL Function being called:

create or replace function public.get_all_reviews()
    returns TABLE(review_text text, review_sentiment integer) as $$
begin
    return query select rec.review_text, rec.review_sentiment from reviews as rec;     
end;
$$ language plpgsql;

ALTER FUNCTION public.get_all_reviews()
    OWNER TO postgres;

C#/NpgSQL:

 public List<Review> GetReviews()
        {
            var reviews = new List<Review>();
            var postgresqlConnection = new NpgsqlConnection("Server=localhost;Port=5432;User Id=user;Password=password;Database=db;");
            postgresqlConnection.Open();

            var command = new NpgsqlCommand("get_all_reviews", postgresqlConnection);
            try
            {
                var dataReader = command.ExecuteReader();

                ...do stuff

                postgresqlConnection.Close();
            }
            catch(Exception ex)
            {
                throw ex;
            }           

            return reviews;
        }

The exception occurs on command.ExecuteReader() . However, if I run the following query in pgAdmin4, I get the desired results from the aforementioned function:

select get_all_reviews()

The SQL that you successfully executed was:

select get_all_reviews()

When you ran it from C# though, you ran different SQL:

get_all_reviews

As such, the solution is to use the working SQL in C# as well:

var command = new NpgsqlCommand("select get_all_reviews()", postgresqlConnection);

This is necessary, since the FUNCTION returns a TABLE, which you are SELECTing from.

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