explicitly casting return value of avg() to float4

Is the preferred way to return the average of ::float4 values to
explicitly cast the returned value of avg() to ::float4?

If so, how do people deal with this in end user apps? Do you check to
see whether the column is ::float8 or ::float4 and then use a different
SQL statement? Ugh, I hope not.

main_v0_8=# select version();
version
-------------------------------------------------------------
PostgreSQL 7.2.1 on i686-pc-linux-gnu, compiled by GCC 2.96
(1 row)

main_v0_8=# select avg(0.01::float4);
avg
---------------------
0.00999999977648258
(1 row)

main_v0_8=# select avg(0.01::float4)::float4;
avg
------
0.01
(1 row)

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Jon Lapham
Extracta Moléculas Naturais, Rio de Janeiro, Brasil
email: lapham(at)extracta(dot)com(dot)br web: http://www.extracta.com.br/
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