Re: [HACKERS] Decimal values in

2014-02-17 Thread Tom Lane
Alvaro Herrera  writes:
> Masterprojekt Naumann1 escribió:
>> inside execProcnode.c's ExecProcNode method we want to extract the value of
>> a tuple for a specific attribute. This works great for integers and
>> strings, but we are not able to figure out how to do this for floating
>> point numbers. Below is some example code snippet to show our problem:

> "DECIMAL_OID" (you probably mean NUMERICOID) points to datatype numeric,
> which is not floating point but a variable length datatype with its own
> special encoding for storage.  If you want floating point you need
> FLOAT4OID and FLOAT8OID, and columns created with types float and
> "double precision", respectively.

Also, you should not be using casts, but the appropriate DatumGetXXX
macro.  In some cases those reduce to a cast, but your code ought not
assume that.

regards, tom lane


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Re: [HACKERS] Decimal values in

2014-02-17 Thread Alvaro Herrera
Masterprojekt Naumann1 escribió:
> Dear Dev-List,
> 
> inside execProcnode.c's ExecProcNode method we want to extract the value of
> a tuple for a specific attribute. This works great for integers and
> strings, but we are not able to figure out how to do this for floating
> point numbers. Below is some example code snippet to show our problem:

"DECIMAL_OID" (you probably mean NUMERICOID) points to datatype numeric,
which is not floating point but a variable length datatype with its own
special encoding for storage.  If you want floating point you need
FLOAT4OID and FLOAT8OID, and columns created with types float and
"double precision", respectively.

-- 
Álvaro Herrerahttp://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services


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