Blank (but not null) columns – PostgreSQL 9.2

All we need is an easy explanation of the problem, so here it is.

Doing by:

select * from ja_customers where id = 8154501

I receive:enter image description here

You can see that all the required fields are “blank” with some invisible character, so they’re not null, so they’re valid (technically)

Question:

How can I see which characters are in there?

How to solve :

I know you bored from this bug, So we are here to help you! Take a deep breath and look at the explanation of your problem. We have many solutions to this problem, But we recommend you to use the first method because it is tested & true method that will 100% work for you.

Method 1

Create a function like the one below and check if a column has a value of empty string (this function return null for an empty string) or an invisible character.

    CREATE FUNCTION get_as_byte_array(anyelement) RETURNS INTEGER[] AS $$
      SELECT
        CASE 
          WHEN length($1::VARCHAR) = 0 THEN NULL
          ELSE
            (SELECT array_agg(get_byte($1::bytea, a)) FROM generate_series(0, length($1::bytea) - 1) a)
        END;
    $$ LANGUAGE SQL;

    SELECT get_as_byte_array(name_first), * FROM ja_customers WHERE id = 8154501;

Method 2

You can use get_byte function to detect which character in specific offset:

SELECT *, get_byte(name_first,0) as firstChar,  get_byte(name_first,0) as secondChar FROM ja_customers WHERE id = 8154501

Note: Use and implement method 1 because this method fully tested our system.
Thank you 🙂

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

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