diff --git a/doc/src/sgml/datatype.sgml b/doc/src/sgml/datatype.sgml new file mode 100644 index 02763b5..f33f29d *** a/doc/src/sgml/datatype.sgml --- b/doc/src/sgml/datatype.sgml *************** NUMERIC *** 681,686 **** --- 681,695 ---- from zero will cause an underflow error. + + The (inherently inaccurate) textual representation of a real + or double precision value will by default contain only as many + significant digits as can be represented without losing precision + on any platform supported by PostgreSQL. The configuration + parameter can be used to + adjust this number. + + not a number double precision