doc: update NUMERIC to state that only some ops are exact

Report by Tom Lane
This commit is contained in:
Bruce Momjian 2015-03-24 19:57:52 -04:00
parent 1d8198bb44
commit 278edd9ed3

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@ -498,11 +498,13 @@
<para> <para>
The type <type>numeric</type> can store numbers with a The type <type>numeric</type> can store numbers with a
very large number of digits and perform calculations exactly. It is very large number of digits. It is especially recommended for
especially recommended for storing monetary amounts and other storing monetary amounts and other quantities where exactness is
quantities where exactness is required. However, arithmetic on required. Calculations with <type>numeric</type> values yield exact
<type>numeric</type> values is very slow compared to the integer results where possible, e.g. addition, subtraction, multiplication.
types, or to the floating-point types described in the next section. However, calculations on <type>numeric</type> values are very slow
compared to the integer types, or to the floating-point types
described in the next section.
</para> </para>
<para> <para>