=== PROBLEM SOLVED ===
I found for what I was looking
http://www.postgresql.org/docs/8.0/static/functions-array.html
Function : array_to_string (anyarray, text)
Return type : text
Description : concatenates array elements using provided delimiter
Example : array_to_string(array[1, 2, 3], '~^~')
Result : 1~^~2~^~3
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