doc: add float as an alias for double precision.

Although the "Floating-Point Types" section says that "float" data
type is taken to mean "double precision", this information was not
reflected in the data type table that lists all data type aliases.

Reported-by: alexander.kjall@hafslund.no
Author: Euler Taveira <euler@eulerto.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/175456294638.800.12038559679827947313@wrigleys.postgresql.org
Backpatch-through: 13

diff --git a/doc/src/sgml/datatype.sgml b/doc/src/sgml/datatype.sgml
index cd82c1c17e0a45b8d22f901af9052118290e17f3..621a1d903197b131472532df2c713ce56aaf1ef5 100644 (file)
--- a/doc/src/sgml/datatype.sgml
+++ b/doc/src/sgml/datatype.sgml
@@ -117,7 +117,7 @@
 
       <row>
        <entry><type>double precision</type></entry>
-       <entry><type>float8</type></entry>
+       <entry><type>float</type>, <type>float8</type></entry>
        <entry>double precision floating-point number (8 bytes)</entry>
       </row>