title: Copy from csv with default values
body: <p>I have CSV file to import in PostgreSQL table with many columns.
  I firstly create a temporary table in which then copy CSV file...</p>
  
  <pre><code>DROP TABLE IF EXISTS mylist;
  CREATE TEMP TABLE mylist (a text, b text, c text, d text, e text, f text, 
                        g text, h text, i text, j text, k text, l text,
                        m text, n text, o text, p text, q text, r text, 
                        s text, t text, u text, v text, w text, 
                        CONSTRAINT popisp_pkey PRIMARY KEY(A));
  
  COPY mylist FROM 'C:\temp\popisp1.csv' DELIMITER AS ';' CSV;
  </code></pre>
  
  <p>This copies data into table but additional problem appear. In fields where is no any data seems that Null is copied but I need an empty string ('').</p>
  
  <p>Is here any way to get empty string where is no data in table cell automatically?<br>
  I was try to add DEFAULT '' to every column declaration but without success.</p>