pgsql: doc: add float as an alias for double precision.

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

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/3a3b1d7ab1809910e51ca19e116080311579d75a

Modified Files
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doc/src/sgml/datatype.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)