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Documentation style improvements

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This commit is contained in:
Peter Eisentraut 2012-06-08 10:28:32 +03:00
parent ece01aae47
commit f1438cf5c6
1 changed files with 29 additions and 31 deletions
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doc/src/sgml/rangetypes.sgml
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@ -35,32 +35,32 @@
<itemizedlist>
<listitem>
<para>
<type>INT4RANGE</type> &mdash; Range of <type>INTEGER</type>
<type>int4range</type> &mdash; Range of <type>integer</type>
</para>
</listitem>
<listitem>
<para>
<type>INT8RANGE</type> &mdash; Range of <type>BIGINT</type>
<type>int8range</type> &mdash; Range of <type>bigint</type>
</para>
</listitem>
<listitem>
<para>
<type>NUMRANGE</type> &mdash; Range of <type>NUMERIC</type>
<type>numrange</type> &mdash; Range of <type>numeric</type>
</para>
</listitem>
<listitem>
<para>
<type>TSRANGE</type> &mdash; Range of <type>TIMESTAMP WITHOUT TIME ZONE</type>
<type>tsrange</type> &mdash; Range of <type>timestamp without time zone</type>
</para>
</listitem>
<listitem>
<para>
<type>TSTZRANGE</type> &mdash; Range of <type>TIMESTAMP WITH TIME ZONE</type>
<type>tstzrange</type> &mdash; Range of <type>timestamp with time zone</type>
</para>
</listitem>
<listitem>
<para>
<type>DATERANGE</type> &mdash; Range of <type>DATE</type>
<type>daterange</type> &mdash; Range of <type>date</type>
</para>
</listitem>
</itemizedlist>
@ -74,9 +74,9 @@
<para>
<programlisting>
CREATE TABLE reservation ( room int, during TSRANGE );
CREATE TABLE reservation (room int, during tsrange);
INSERT INTO reservation VALUES
( 1108, '[2010-01-01 14:30, 2010-01-01 15:30)' );
(1108, '[2010-01-01 14:30, 2010-01-01 15:30)');
-- Containment
SELECT int4range(10, 20) @> 3;
@ -223,16 +223,16 @@ empty
Examples:
<programlisting>
-- includes 3, does not include 7, and does include all points in between
select '[3,7)'::int4range;
SELECT '[3,7)'::int4range;
-- does not include either 3 or 7, but includes all points in between
select '(3,7)'::int4range;
SELECT '(3,7)'::int4range;
-- includes only the single point 4
select '[4,4]'::int4range;
SELECT '[4,4]'::int4range;
-- includes no points (and will be normalized to 'empty')
select '[4,4)'::int4range;
SELECT '[4,4)'::int4range;
</programlisting>
</para>
</sect2>
@ -279,13 +279,13 @@ SELECT numrange(NULL, 2.2);
<para>
A discrete range is one whose element type has a well-defined
<quote>step</quote>, such as <type>INTEGER</type> or <type>DATE</type>.
<quote>step</quote>, such as <type>integer</type> or <type>date</type>.
In these types two elements can be said to be adjacent, when there are
no valid values between them. This contrasts with continuous ranges,
where it's always (or almost always) possible to identify other element
values between two given values. For example, a range over the
<type>NUMERIC</> type is continuous, as is a range over <type>TIMESTAMP</>.
(Even though <type>TIMESTAMP</> has limited precision, and so could
<type>numeric</> type is continuous, as is a range over <type>timestamp</>.
(Even though <type>timestamp</> has limited precision, and so could
theoretically be treated as discrete, it's better to consider it continuous
since the step size is normally not of interest.)
</para>
@ -313,8 +313,8 @@ SELECT numrange(NULL, 2.2);
</para>
<para>
The built-in range types <type>INT4RANGE</type>, <type>INT8RANGE</type>,
and <type>DATERANGE</type> all use a canonical form that includes
The built-in range types <type>int4range</type>, <type>int8range</type>,
and <type>daterange</type> all use a canonical form that includes
the lower bound and excludes the upper bound; that is,
<literal>[)</literal>. User-defined range types can use other conventions,
however.
@ -332,8 +332,8 @@ SELECT numrange(NULL, 2.2);
<programlisting>
CREATE TYPE floatrange AS RANGE (
subtype = float8,
subtype_diff = float8mi
subtype = float8,
subtype_diff = float8mi
);
SELECT '[1.234, 5.678]'::floatrange;
@ -451,8 +451,7 @@ CREATE INDEX reservation_idx ON reservation USING gist (during);
range type. For example:
<programlisting>
ALTER TABLE reservation
ADD EXCLUDE USING gist (during WITH &amp;&amp;);
ALTER TABLE reservation ADD EXCLUDE USING gist (during WITH &amp;&amp;);
</programlisting>
That constraint will prevent any overlapping values from existing
@ -460,11 +459,11 @@ ALTER TABLE reservation
<programlisting>
INSERT INTO reservation VALUES
( 1108, '[2010-01-01 11:30, 2010-01-01 13:00)' );
(1108, '[2010-01-01 11:30, 2010-01-01 13:00)');
INSERT 0 1
INSERT INTO reservation VALUES
( 1108, '[2010-01-01 14:45, 2010-01-01 15:45)' );
(1108, '[2010-01-01 14:45, 2010-01-01 15:45)');
ERROR: conflicting key value violates exclusion constraint "reservation_during_excl"
DETAIL: Key (during)=([ 2010-01-01 14:45:00, 2010-01-01 15:45:00 )) conflicts
with existing key (during)=([ 2010-01-01 14:30:00, 2010-01-01 15:30:00 )).
@ -480,25 +479,24 @@ with existing key (during)=([ 2010-01-01 14:30:00, 2010-01-01 15:30:00 )).
are equal:
<programlisting>
CREATE TABLE room_reservation
(
room TEXT,
during TSRANGE,
EXCLUDE USING gist (room WITH =, during WITH &amp;&amp;)
CREATE TABLE room_reservation (
room text,
during tsrange,
EXCLUDE USING gist (room WITH =, during WITH &amp;&amp;)
);
INSERT INTO room_reservation VALUES
( '123A', '[2010-01-01 14:00, 2010-01-01 15:00)' );
('123A', '[2010-01-01 14:00, 2010-01-01 15:00)');
INSERT 0 1
INSERT INTO room_reservation VALUES
( '123A', '[2010-01-01 14:30, 2010-01-01 15:30)' );
('123A', '[2010-01-01 14:30, 2010-01-01 15:30)');
ERROR: conflicting key value violates exclusion constraint "room_reservation_room_during_excl"
DETAIL: Key (room, during)=(123A, [ 2010-01-01 14:30:00, 2010-01-01 15:30:00 )) conflicts with
existing key (room, during)=(123A, [ 2010-01-01 14:00:00, 2010-01-01 15:00:00 )).
INSERT INTO room_reservation VALUES
( '123B', '[2010-01-01 14:30, 2010-01-01 15:30)' );
('123B', '[2010-01-01 14:30, 2010-01-01 15:30)');
INSERT 0 1
</programlisting>
</para>