Splitting a comma-separated field in Postgresql and doing a UNION ALL on all the resulting tables

Question

I have a table that contains a field of comma separated strings:

ID | fruits
-----------
1  | cherry,apple,grape 
2  | apple,orange,peach 

I want to create a normalized version of the table, like this:

ID | fruits
-----------
1  | cherry 
1  | apple 
1  | grape
2  | apple 
2  | orange 
2  | peach 

The postgresql 8.4 documentation describes a regexp_split_to_table function that can turn a single table:

SELECT foo 
FROM regexp_split_to_table('the quick brown fox jumped over the lazy dog',E'\\s+') AS
foo;

which gives you this:

  foo   
--------
  the    
  quick  
  brown  
  fox    
  jumped 
  over   
  the    
  lazy   
  dog    
 (9 rows)

But that is just for a single field. What I want to do is some kind UNION applied to all the tables generated by splitting each field. Thank you.

Leakage

Answer 1

This should give you the output you're looking for:

SELECT 
    yourTable.ID, 
    regexp_split_to_table(yourTable.fruits, E',') AS split_fruits
FROM yourTable

EDIT: Fixed the regex.

Hiss

can you please help me with #40006474 – Couscous

i tried SELECT CATEGORI.ID, regexp_split_to_table(CATEGORI.CATEGORY, E',') AS split_fruits FROM CATEGORI; – Couscous

it works but i want to filter duplicate data from it – Couscous

What's the E for? – Cleopatra