2010/7/12 Itagaki Takahiro <itagaki.takah...@gmail.com>: > 2010/7/12 Pavel Stehule <pavel.steh...@gmail.com>: >> I prefere a new names - because there are a new behave - with little >> bit better default handling of NULL values. string_to_array and >> array_to_string just ignore NULL values - what isn't correct behave. >> Later we can mark these functions as deprecated and remove it. If I >> use current function, then we have to continue in current behave. > > I prefer existing names because your new default behavior can be done > with suitable nullstr values. IMHO, new names will be acceptable only if > they are listed in the SQL-standard or many other databases use the > names. Two similar versions of functions must confuse users.
there is different default behave. So if you don't need to use a third argument > > Also, are there any consensus about "existing functions are not correct" ? > Since string_agg() and your new concat() functions ignores NULLs, > I think it is not so bad for array_to_string() to ignore NULLs. string_agg is a aggregate function - there are NULLS ignored usually, concat simulate MySQL behave - and more, there are not problem to use a coalesce function. string_to_arrays and array_to string are different - there you cannot use a coalesce. Why string_to_array and array_to_strings are not correct? a) what is correct sample of using a array_to_string with NULL ignoring?? Usually, when you have a NULL in array, you don't want to loose this value. b) for me - these functions are some of serialisation/deserialisation functions - usually people don't want to miss any value. I searching in history - my first proposal was similar to your: http://www.mail-archive.com/pgsql-hackers@postgresql.org/msg151474.html http://www.mail-archive.com/pgsql-hackers@postgresql.org/msg151503.html !! if you look on this thread, you can see so I was unsure and confused too - but now I inclinded to Merlin's proposal shortly: * string_to_array/array_to_string ignore nulls * others not aggregates not ignore nulls * default for NULL isn't "NULL" but empty string - like csv regards Pavel Stěhule > > -- > Itagaki Takahiro > -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
