carlos_penteado@yahoo.com.br writes:
> SELECT 109048.96::float, 0.96::float
> RETURNS
> 109048.96;0.96
> but
> SELECT 109048.96::real, 0.96::real
> RETURNS
> 109049;0.96
"float" means float8, while "real" means float4. Per
http://www.postgresql.org/docs/9.5/static/datatype-numeric.html#DATATYPE-FLOAT
PostgreSQL also supports the SQL-standard notations float and float(p)
for specifying inexact numeric types. Here, p specifies the minimum
acceptable precision in binary digits. PostgreSQL accepts float(1) to
float(24) as selecting the real type, while float(25) to float(53)
select double precision. Values of p outside the allowed range draw an
error. float with no precision specified is taken to mean double
precision.
regards, tom lane