假脱机截断十进制数据

Question

I'm doing a quite easy query (sum a column):

select 
SUM (txn.amt_val) AS monto
from siebel.s_loy_txn txn 

The query result is 791412524.16 but when I do a spool, the result I get is truncated.

So: 791412524

The full query is something like this -->

SET serveroutput ON SIZE 1000000;
SET pages 0;
SET linesize 15000;
SET heading OFF;
SET verify OFF;
SET echo OFF;
SET feedback OFF;
SET term OFF;
SET trims ON;

Spool 'C:\Users\Report.txt' --spoolname from dual;

Select 
SUM (txn.amt_val) AS monto
from siebel.s_loy_txn txn;


SPOOL off

Answer 1

也许明确地将数字转换为足够长的char？

select cast(txn.amt_val as char(20)) as monto from siebel.s_loy_txn txn;

Answer 2

The default numwidth in SQL*Plus is 10. In combination with the default numformat means it shows up to ten significant digits for a decimal value; it's implicitly rounding the decimal up in this case, rather than truncating. If your result was 91412524.16 you would see 91412524.2.

This is described in the documentation :

SQL*Plus normally displays numbers with as many digits as are required for accuracy, up to a standard display width determined by the value of the NUMWIDTH variable of the SET command (normally 10). If a number is larger than the value of SET NUMWIDTH, SQL*Plus rounds the number up or down to the maximum number of characters allowed if possible, or displays hashes if the number is too large.

... though that isn't particularly clear.

You can just make numwidth larger, to at least 12 in this case; or set numformat to explicitly include decimals (optionally with fm to suppress leading blanks and trailing zeros),; or use to_char() with a similar mask; or as CZ Zhu suggested you can cast which has the same effect but is less obvious.

Testing all those options:

-- default numwidth and numformat
select 791412524.16 from dual;

set numwidth 11
select 791412524.16 from dual;

set numwidth 12
select 791412524.16 from dual;

set numwidth 10
set numformat fm999999999999999.99999
select 791412524.16 from dual;

set numformat ""
select to_char(791412524.16, 'fm999999999999999.99999') from dual;

select cast(791412524.16 as varchar2(20)) from dual;

Which gets:

   791412524
 791412524.2
791412524.16
791412524.16
791412524.16
791412524.16

The question is tagged for SQL Developer, but as the pagesize you're using errors in that, you seem to be using SQL*Plus. The same thing does apply to SQL Developer too, except its default numformat is less friendly, giving you 7.9E+08 . Changing numwidth doesn't help, but the other versions get the full value in SQL Developer too.