-- packages/acs-events/sql/timespan-create.sql
--
-- This script defines the data models and API for both time_interval and timespan.
--
-- @author smeeks@arsdigita.com
-- @creation-date 2000-11-16
--
-- $Id: timespan-create.sql,v 1.9.2.1 2023/05/29 09:39:06 gustafn Exp $
create sequence timespan_sequence start 1;
-- create view timespan_seq as select nextval('timespan_sequence') as nextval from dual;
-- Table for storing time intervals. Note that time intervals can be open on
-- either end. This is represented by a null value for start_date or end_date.
-- Applications can determine how to interpret null values. However, this is
-- the default interpretation used by the overlaps_p functions. A null value
-- for start_date is treated as extending to the beginning of time. A null
-- value for end_date is treated as extending to the end of time. The net effect
-- is that an interval with an open start overlaps any interval whose start
-- is before the end of the interval with the open start. Likewise, an interval
-- with an open end overlaps any interval whose end is after the start of the
-- interval with the open end.
create table time_intervals (
interval_id integer
constraint time_intervals_pk
primary key,
start_date timestamptz,
end_date timestamptz,
constraint time_interval_date_order_ck
check(start_date <= end_date)
);
create index time_intervals_start_idx on time_intervals(start_date);
comment on table time_intervals is '
A time interval is represented by two points in time.
';
-- API:
--
-- new (start_date, end_date)
-- delete ()
--
-- edit (start_date, end_date)
--
-- shift (start_offset, end_offset)
--
-- overlaps_p (interval_id)
-- overlaps_p (start_date, end_date)
--
-- added
select define_function_args('time_interval__new','start_date;null,end_date;null');
--
-- procedure time_interval__new/2
--
--
-- Creates a new time interval
--
-- @author W. Scott Meeks
--
-- @param start_date Sets this as start_date of new interval
-- @param end_date Sets this as end_date of new interval
--
-- @return id of new time interval
--
CREATE OR REPLACE FUNCTION time_interval__new(
new__start_date timestamptz, -- default null
new__end_date timestamptz -- default null
) RETURNS integer AS $$
DECLARE
v_interval_id time_intervals.interval_id%TYPE;
BEGIN
select nextval('timespan_sequence') into v_interval_id from dual;
insert into time_intervals
(interval_id, start_date, end_date)
values
(v_interval_id, new__start_date, new__end_date);
return v_interval_id;
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('time_interval__delete','interval_id');
--
-- procedure time_interval__delete/1
--
--
-- Deletes the given time interval
--
-- @author W. Scott Meeks
--
-- @param interval_id id of the interval to delete
--
-- @return 0 (procedure dummy)
--
CREATE OR REPLACE FUNCTION time_interval__delete(
delete__interval_id integer
) RETURNS integer AS $$
DECLARE
BEGIN
delete from time_intervals
where interval_id = delete__interval_id;
return 0;
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('time_interval__edit','interval_id,start_date;null,end_date;null');
--
-- procedure time_interval__edit/3
--
--
-- Updates the start_date or end_date of an interval
--
-- @author W. Scott Meeks
--
-- @param interval_id id of the interval to update
-- @param start_date Sets this as the new
-- start_date of the interval.
-- @param end_date Sets this as the new
-- end_date of the interval.
--
-- @return 0 (procedure dummy)
--
CREATE OR REPLACE FUNCTION time_interval__edit(
edit__interval_id integer,
edit__start_date timestamptz, -- default null
edit__end_date timestamptz -- default null
) RETURNS integer AS $$
DECLARE
BEGIN
-- JS: I hate deeply nested if-else-ifs!!!
-- Null for start_date or end_date means don't change.
if edit__start_date is not null and edit__end_date is not null then
update time_intervals
set start_date = edit__start_date,
end_date = edit__end_date
where interval_id = edit__interval_id;
end if;
-- Update only the end date if not null even if start date is null
if edit__start_date is not null and edit__end_date is null
then
update time_intervals
set start_date = edit__start_date
where interval_id = edit__interval_id;
end if;
-- Update only the start date if not null even if end date is null
if edit__end_date is not null and edit__start_date is null
then
update time_intervals
set end_date = edit__end_date
where interval_id = edit__interval_id;
end if;
return 0;
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('time_interval__shift','interval_id,start_offset;0,end_offset;0');
--
-- procedure time_interval__shift/3
--
--
-- Updates the start_date or end_date of an interval based on offsets (general)
--
-- @author W. Scott Meeks
-- @param interval_id The interval to update.
-- @param start_offset Adds this date interval to the
-- start_date of the interval. No effect if
-- start_date is null.
-- @param end_offset Adds this date interval to the
-- end_date of the interval. No effect if
-- end_date is null.
--
-- @return 0 (procedure dummy)
--
CREATE OR REPLACE FUNCTION time_interval__shift(
shift__interval_id integer,
shift__start_offset interval, -- default 0,
shift__end_offset interval -- default 0
) RETURNS integer AS $$
DECLARE
BEGIN
update time_intervals
set start_date = start_date + shift__start_offset,
end_date = end_date + shift__end_offset
where interval_id = shift__interval_id;
return 0;
END;
$$ LANGUAGE plpgsql;
--
-- procedure time_interval__shift/3
--
--
-- Updates the start_date or end_date of an interval based on offsets of
-- fractional days.
--
-- JS: Overloaded function to make above compatible with Oracle behavior
-- JS: when an integer (for number of days) is supplied as a parameter.
--
-- @param interval_id The interval to update.
-- @param start_offset Adds this number of days to the
-- start_date of the interval. No effect if
-- start_date is null.
-- @param end_offset Adds this number of days to the
-- end_date of the interval. No effect if
-- end_date is null.
--
-- @return 0 (procedure dummy)
CREATE OR REPLACE FUNCTION time_interval__shift(
shift__interval_id integer,
shift__start_offset integer, -- default 0,
shift__end_offset integer -- default 0
) RETURNS integer AS $$
DECLARE
BEGIN
return time_interval__shift(
shift__interval_id,
to_interval(shift__start_offset,'days'),
to_interval(shift__end_offset,'days')
);
END;
$$ LANGUAGE plpgsql;
-- added
--
-- procedure time_interval__overlaps_p/2
--
--
-- Returns true if the two intervals overlap, false otherwise.
--
-- @author W. Scott Meeks
--
-- @param interval_1_id
-- @param interval_2_id
--
-- @return true if the two intervals overlap, false otherwise.
--
CREATE OR REPLACE FUNCTION time_interval__overlaps_p(
overlaps_p__interval_id_1 integer,
overlaps_p__interval_id_2 integer
) RETURNS boolean AS $$
DECLARE
v_start_1 timestamptz;
v_start_2 timestamptz;
v_end_1 timestamptz;
v_end_2 timestamptz;
BEGIN
-- Pull out the start and end dates and call the main overlaps_p.
select start_date, end_date
into v_start_1, v_end_1
from time_intervals
where interval_id = overlaps_p__interval_id_1;
select start_date, end_date
into v_start_2, v_end_2
from time_intervals
where interval_id = overlaps_p__interval_id_2;
return time_interval__overlaps_p(
v_start_1,
v_end_1,
v_start_2,
v_end_2
);
END;
$$ LANGUAGE plpgsql;
--
-- procedure time_interval__overlaps_p/3
--
--
-- Returns true if the interval bounded by the given start_date or
-- end_date overlaps the given interval, false otherwise.
--
-- @author W. Scott Meeks
--
-- @param start_date See if it overlaps the interval starting from this date.
-- @param end_date See if it overlaps the interval ending on this date.
--
-- @return true if the interval bounded by start_date through end_date, false otherwise.
--
CREATE OR REPLACE FUNCTION time_interval__overlaps_p(
overlaps_p__interval_id integer,
overlaps_p__start_date timestamptz, -- default null,
overlaps_p__end_date timestamptz -- default null
) RETURNS boolean AS $$
DECLARE
v_interval_start time_intervals.start_date%TYPE;
v_interval_end time_intervals.end_date%TYPE;
BEGIN
-- Pull out the start and end date and call the main overlaps_p.
select start_date, end_date
into v_interval_start, v_interval_end
from time_intervals
where interval_id = overlaps_p__interval_id;
return time_interval__overlaps_p(
v_interval_start,
v_interval_end,
overlaps_p__start_date,
overlaps_p__end_date
);
END;
$$ LANGUAGE plpgsql;
--
-- procedure time_interval__overlaps_p/4
--
--
-- Checks if two intervals overlaps
-- JS: There is a simpler way to evaluate whether intervals overlap,
-- JS: so this function can be optimized.
--
-- @author W. Scott Meeks
--
-- @param interval_1_id First interval
-- @param interval_2_id Second interval
--
-- @return true if intervals overlap, otherwise false.
--
select define_function_args('time_interval__overlaps_p','start_1,end_1,start_2,end_2');
CREATE OR REPLACE FUNCTION time_interval__overlaps_p(
overlaps_p__start_1 timestamptz,
overlaps_p__end_1 timestamptz,
overlaps_p__start_2 timestamptz,
overlaps_p__end_2 timestamptz
) RETURNS boolean AS $$
DECLARE
BEGIN
-- JS: Modified yet another deeply nested if-else-if
-- JS: Note that null date is the representation for infinite
-- (positive or negative) time.
if overlaps_p__start_1 is null
then
-- No overlap if 2nd interval starts after 1st ends
if overlaps_p__end_1 < overlaps_p__start_2
then
return false;
else
return true;
end if;
end if;
if overlaps_p__start_2 is null
then
-- No overlap if 2nd interval ends before 1st starts
if overlaps_p__end_2 < overlaps_p__start_1
then
return false;
else
return true;
end if;
end if;
-- Okay, both start dates are not null
if overlaps_p__start_1 <= overlaps_p__start_2
then
-- 1st starts before 2nd
if overlaps_p__end_1 < overlaps_p__start_2
then
-- No overlap if 1st ends before 2nd starts
return false;
else
-- No overlap or at least one null
return true;
end if;
else
-- 1st starts after 2nd
if overlaps_p__end_2 < overlaps_p__start_1
then
-- No overlap if 2nd ends before 1st starts
return false;
else
-- No overlap or at least one null
return true;
end if;
end if;
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('time_interval__eq','interval_1_id,interval_2_id');
--
-- procedure time_interval__eq/2
--
--
-- Checks if two intervals are equal
--
-- @author W. Scott Meeks
--
-- @param interval_1_id First interval
-- @param interval_2_id Second interval
--
-- @return true if intervals are equal, otherwise false.
--
CREATE OR REPLACE FUNCTION time_interval__eq(
eq__interval_1_id integer,
eq__interval_2_id integer
) RETURNS boolean AS $$
-- return boolean
DECLARE
interval_1_row time_intervals%ROWTYPE;
interval_2_row time_intervals%ROWTYPE;
BEGIN
select * into interval_1_row
from time_intervals
where interval_id = eq__interval_1_id;
select * into interval_2_row
from time_intervals
where interval_id = eq__interval_2_id;
if interval_1_row.start_date = interval_2_row.start_date and
interval_1_row.end_date = interval_2_row.end_date
then
return true;
else
return false;
end if;
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('time_interval__copy','interval_id,offset;0');
--
-- procedure time_interval__copy/2
--
--
-- Creates a new copy of a time interval, offset by optional offset
--
-- JS: We need to be careful in interpreting the copy offset.
-- JS: Oracle interprets integers as full days when doing
-- JS: date arithmetic. Thus,
-- JS:
-- JS: select sysdate()+1 from dual;
-- JS:
-- JS: will yield the next date, correct up to the second of the next day
-- JS: that the query was run.
-- JS:
-- JS: In PostgreSQL, we need to specify the type of interval when
-- JS: doing date arithmetic. if, say, an integer is used in date arithmetic,
-- JS: the results are weird. For example,
-- JS:
-- JS: select now()+1 from dual;
-- JS:
-- JS: will yield the MIDNIGHT of the next date that the query was run, i.e.,
-- JS: the timestamp is typecasted as a date with a day granularity. To get the
-- JS: same effect as Oracle, we need to use explicitly typecast the integer into
-- JS: a day interval.
--
-- @author W. Scott Meeks
--
-- @param interval_id Interval to copy
-- @param offset Interval is offset by this date interval
--
-- @return interval_id of the copied interval
CREATE OR REPLACE FUNCTION time_interval__copy(
copy__interval_id integer,
copy__offset interval -- default 0
) RETURNS integer AS $$
DECLARE
interval_row time_intervals%ROWTYPE;
v_foo timestamptz;
BEGIN
select * into interval_row
from time_intervals
where interval_id = copy__interval_id;
return time_interval__new(
(interval_row.start_date ::timestamp + copy__offset) :: timestamptz,
(interval_row.end_date ::timestamp + copy__offset) :: timestamptz
);
END;
$$ LANGUAGE plpgsql;
--
-- procedure time_interval__copy/1
--
--
-- Creates a new copy of a time interval.
-- JS: Overloaded version of above, no offset
--
-- @param interval_id Interval to copy
--
-- @return interval_id of the copied interval
--
CREATE OR REPLACE FUNCTION time_interval__copy(
copy__interval_id integer
) RETURNS integer AS $$
-- return time_intervals.interval_id%TYPE
DECLARE
v_query varchar;
v_result time_intervals.interval_id%TYPE;
rec_datecalc record;
BEGIN
return time_interval__copy(
copy__interval_id,
interval '0 days'
);
END;
$$ LANGUAGE plpgsql;
--
-- procedure time_interval__copy/2
--
--
-- Creates a new copy of a time interval, offset by optional offset
--
-- JS: Overloaded function to make above compatible with Oracle behavior
-- JS: when an integer (for number of days) is supplied as a parameter.
--
-- @param interval_id Interval to copy
-- @param offset Interval is offset by this number of days
--
-- @return interval_id of the copied interval
--
CREATE OR REPLACE FUNCTION time_interval__copy(
copy__interval_id integer,
copy__offset integer -- default 0
) RETURNS integer AS $$
DECLARE
BEGIN
return time_interval__copy(
copy__interval_id,
to_interval(copy__offset,'days')
);
END;
$$ LANGUAGE plpgsql;
-- Timespans table. A timespan is a set of intervals. This table contains
-- mappings of intervals into a set that comprises a timespan.
create table timespans (
-- Can't be primary key because of the one to many relationship with
-- interval_id, but we can declare it not null and index it.
timespan_id integer not null,
interval_id integer
constraint tm_ntrvl_sts_interval_id_fk
references time_intervals on delete cascade
);
create index timespans_idx on timespans(timespan_id);
-- This is important to prevent locking on update of master table.
-- See http://www.arsdigita.com/bboard/q-and-a-fetch-msg.tcl?msg_id=000KOh
-- JS: Not sure if this applies to PostgreSQL, but an index can't hurt, can it?
create index timespans_interval_id_idx on timespans(interval_id);
comment on table timespans is '
Establishes a relationship between timespan_id and multiple time
intervals. Represents a range of moments at which an event can occur.
';
-- TimeSpan API
--
-- Quick reference for the API supported for timespans. All procedures take timespan_id
-- as the first argument (not shown explicitly):
--
-- new (interval_id)
-- new (start_date, end_date)
-- delete ()
--
-- Methods to join additional time intervals with an existing timespan:
--
-- join (timespan_id)
-- join_interval (interval_id)
-- join (start_date, end_date)
--
-- interval_delete (interval_id)
-- interval_list ()
--
-- Tests for overlap:
--
-- overlaps_p (timespan_id)
-- overlaps_p (interval_id)
-- overlaps_p (start_date, end_date)
--
-- Info:
--
-- exists_p ()
-- multi_interval_p ()
-- added
--
-- procedure timespan__new/2
--
--
-- Creates a new timespan (20.20.10)
-- given a time_interval
--
-- JS: Allow user to specify whether the itme interval is to be copied or not
-- JS: This gives more flexibility of not making a copy instead of requiring
-- JS: the caller responsible for deleting the copy.
--
-- @author W. Scott Meeks
--
-- @param interval_id Id of interval to be included/copied in timespan,
-- @param copy_p If true, make another copy of the interval,
-- else simply include the interval in the timespan
--
-- @return Id of new timespan
--
CREATE OR REPLACE FUNCTION timespan__new(
new__interval_id integer,
new__copy_p boolean
) RETURNS integer AS $$
-- timespans.timespan_id%TYPE
DECLARE
v_timespan_id timespans.timespan_id%TYPE;
v_interval_id time_intervals.interval_id%TYPE;
BEGIN
-- get a new id;
select nextval('timespan_sequence') into v_timespan_id from dual;
if new__copy_p
then
-- JS: Note use of overloaded function (zero offset)
v_interval_id := time_interval__copy(new__interval_id);
else
v_interval_id := new__interval_id;
end if;
insert into timespans
(timespan_id, interval_id)
values
(v_timespan_id, v_interval_id);
return v_timespan_id;
END;
$$ LANGUAGE plpgsql;
-- end new;
--
-- procedure timespan__new/1
--
--
-- Creates a new timespan (20.20.10)
-- given a time_interval
--
-- JS: I understand why we want to copy here (since interval_id
-- JS: may be used by another), but see note on time_span__copy
-- JS: below. THE ONLY REASON WHY DEFAULT IS TRUE IS TO MAINTAIN
-- JS: COMPATIBILITY WITH ORIGINAL VERSION. I DO NOT THINK TRUE
-- JS: SHOULD BE THE DEFAULT.
--
-- @param interval_id Id of interval to be copied in timespan,
--
-- @return Id of new timespan
--
CREATE OR REPLACE FUNCTION timespan__new(
new__interval_id integer
) RETURNS integer AS $$
DECLARE
BEGIN
return timespan__new(
new__interval_id,
true
);
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('timespan__new','start_date;null,end_date;null');
--
-- procedure timespan__new/2
--
--
-- Creates a new timespan (20.20.10)
-- given a start date and end date. A new time interval with the
-- start and end dates is automatically created.
--
-- @param start_date Start date of interval to be included/copied in timespan,
-- @param end_date End date of interval to be included/copied in timespan,
--
-- @return Id of new timespan
--
CREATE OR REPLACE FUNCTION timespan__new(
new__start_date timestamptz, -- default null,
new__end_date timestamptz -- default null
) RETURNS integer AS $$
DECLARE
BEGIN
-- JS: If we simply call timespan__new with default copy_p = true,
-- JS: there will be two new time intervals that will be created
-- JS: every time this function is called. The first one will never be used!!!
-- JS: To fix, we use the timespan__new with copy_p parameter and
-- JS: setting copy_p to false.
return timespan__new(time_interval__new(new__start_date, new__end_date),false);
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('timespan__delete','timespan_id');
--
-- procedure timespan__delete/1
--
--
-- Deletes the timespan and any contained intervals
--
-- @author W. Scott Meeks
--
-- @param timespan_id Id of timespan to delete
--
-- @return 0 (procedure dummy)
--
CREATE OR REPLACE FUNCTION timespan__delete(
delete__timespan_id integer
) RETURNS integer AS $$
DECLARE
BEGIN
-- Delete intervals, corresponding timespan entries deleted by
-- cascading constraints
delete from time_intervals
where interval_id in (select interval_id
from timespans
where timespan_id = delete__timespan_id);
return 0;
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('timespan__join_interval','timespan_id,interval_id,copy_p;true');
--
-- procedure timespan__join_interval/3
--
--
-- Join a time interval to an existing timespan
--
-- JS: Slight changes from original
-- JS: Return the interval_id being joined, since it will not be the
-- JS: same as join_interval__interval_id if join_interval__copy_p is true
-- JS: The Oracle version is a procedure, so this change is completely free.
--
-- @author W. Scott Meeks
--
-- @param timespan_id Id of timespan to join to
-- @param interval_id Id of interval to include/copy into timespan
-- @param copy_p If true, make a new copy of he interval for inclusion
-- into the timespan, otherwise simply include the interval
--
-- @return Id of interval being joined
--
CREATE OR REPLACE FUNCTION timespan__join_interval(
join_interval__timespan_id integer,
join_interval__interval_id integer,
join_interval__copy_p boolean -- default true
) RETURNS integer AS $$
-- time_intervals.interval_id%TYPE
DECLARE
v_interval_id time_intervals.interval_id%TYPE;
BEGIN
if join_interval__copy_p then
v_interval_id := time_interval__copy(join_interval__interval_id);
else
v_interval_id := join_interval__interval_id;
end if;
insert into timespans
(timespan_id, interval_id)
values
(join_interval__timespan_id, v_interval_id);
-- JS: We might as well return the interval id being joined, instead of returning a dummy integer
return v_interval_id;
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('timespan__join','timespan_id,start_date;null,end_date;null');
--
-- procedure timespan__join/3
--
--
-- Join a new interval with start and end dates to an existing timespan
--
-- JS: Slight change from original
-- JS: Return the interval_id being joined (Oracle version is a procedure)
--
-- @author W. Scott Meeks
--
-- @param timespan_id Id of timespan to join new interval
-- @param start_date Start date of new interval to join to timespan
-- @param end_date End date of new interval to join to timespan
--
-- @return Id of interval being joined
--
CREATE OR REPLACE FUNCTION timespan__join(
join__timespan_id integer,
join__start_date timestamptz, -- default null,
join__end_date timestamptz -- default null
) RETURNS integer AS $$
DECLARE
BEGIN
-- JS: This will create a new interval with start_date and end_date
-- JS: so we might as well return the interval id
return timespan__join_interval(
join__timespan_id,
time_interval__new(join__start_date, join__end_date),
false
);
END;
$$ LANGUAGE plpgsql;
--
-- procedure timespan__join/2
--
--
-- Join a new timespan or time interval to an existing timespan
--
-- JS: Slight changes from original
-- JS: Return the last interval_id being joined. Although probably not useful
-- JS: we return the interval_id anyways to make the function consisted with
-- JS: the rest. Oracle version is a procedure.
--
-- @author W. Scott Meeks
--
-- @param timespan_id Id of timespan to join to
-- @param timespan_id Id of timespan to join from
--
-- @return Id of last interval in timespan being joined
--
CREATE OR REPLACE FUNCTION timespan__join(
join__timespan_1_id integer,
join__timespan_2_id integer
) RETURNS integer AS $$
DECLARE
v_interval_id time_intervals.interval_id%TYPE;
rec_timespan record;
BEGIN
-- Loop over intervals in 2nd timespan, join with 1st.
for rec_timespan in
select *
from timespans
where timespan_id = join__timespan_2_id
loop
v_interval_id := timespan__join_interval(
join__timespan_1_id,
rec_timespan.interval_id,
false
);
end loop;
-- JS: Return the last interval id joined. Not very useful, since there may be
-- JS: more than one interval joined
return v_interval_id;
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('timespan__interval_delete','timespan_id,interval_id');
--
-- procedure timespan__interval_delete/2
--
--
-- Deletes an interval from the given timespan
--
-- @author W. Scott Meeks
--
-- @param timespan_id timespan to delete from
-- @param interval_id delete this interval from the set
--
-- @return 0 (procedure dummy)
--
CREATE OR REPLACE FUNCTION timespan__interval_delete(
interval_delete__timespan_id integer,
interval_delete__interval_id integer
) RETURNS integer AS $$
DECLARE
BEGIN
delete from timespans
where timespan_id = interval_delete__timespan_id
and interval_id = interval_delete__interval_id;
return 0;
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('timespan__exists_p','timespan_id');
--
-- procedure timespan__exists_p/1
--
--
-- If its contained intervals are all deleted, then a timespan will
-- automatically be deleted. This checks a timespan_id to make sure it is
-- still valid.
--
-- @author W. Scott Meeks
--
-- @param timespan_id id of timespan to check
--
-- @return true if interval is in timespan set, otherwise false.
--
CREATE OR REPLACE FUNCTION timespan__exists_p(
exists_p__timespan_id integer
) RETURNS boolean AS $$
DECLARE
v_result integer;
BEGIN
-- Only need to check if any rows exist.
select count(*)
into v_result
from dual
where exists (select timespan_id
from timespans
where timespan_id = exists_p__timespan_id);
if v_result = 0 then
return false;
else
return true;
end if;
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('timespan__multi_interval_p','timespan_id');
--
-- procedure timespan__multi_interval_p/1
--
--
-- Checks if timespan contains more than one interval
--
-- @author W. Scott Meeks
--
-- @param timespan_id id of timespan to check
--
-- @return true if timespan has more than one interval, otherwise false.
--
CREATE OR REPLACE FUNCTION timespan__multi_interval_p(
multi_interval_p__timespan_id integer
) RETURNS boolean AS $$
DECLARE
v_result boolean;
BEGIN
-- 'f' if 0 or 1 intervals, 't' otherwise
-- use the simple case syntax
select (case count(timespan_id)
when 0 then false
when 1 then false
else true
end)
into v_result
from timespans
where timespan_id = multi_interval_p__timespan_id;
return v_result;
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('timespan__overlaps_interval_p','timespan_id,interval_id;null');
--
-- procedure timespan__overlaps_interval_p/2
--
--
-- Checks to see interval overlaps any of the intervals in the timespan.
--
-- @author W. Scott Meeks
--
-- @param timespan_id id of timespan as reference
-- @param timespan_id id of timespan to check
--
-- @return true if interval overlaps with anyinterval in timespan, otherwise false.
--
CREATE OR REPLACE FUNCTION timespan__overlaps_interval_p(
overlaps_interval_p__timespan_id integer,
overlaps_interval_p__interval_id integer -- default null
) RETURNS boolean AS $$
DECLARE
v_start_date timestamptz;
v_end_date timestamptz;
BEGIN
select start_date, end_date
into v_start_date, v_end_date
from time_intervals
where interval_id = overlaps_interval_p__interval_id;
return timespan__overlaps_p(
overlaps_interval_p__timespan_id,
v_start_date,
v_end_date
);
END;
$$ LANGUAGE plpgsql;
-- added
--
-- procedure timespan__overlaps_p/2
--
--
-- Checks to see if any intervals in a timespan overlap any of the intervals
-- in the second timespan.
--
-- @author W. Scott Meeks
--
-- @param timespan_id id of timespan as reference
-- @param timespan_id id of timespan to check
--
CREATE OR REPLACE FUNCTION timespan__overlaps_p(
overlaps_p__timespan_1_id integer,
overlaps_p__timespan_2_id integer
) RETURNS boolean AS $$
DECLARE
v_result boolean;
rec_timespan record;
BEGIN
-- Loop over 2nd timespan, checking each interval against 1st
for rec_timespan in
select *
from timespans
where timespan_id = overlaps_p__timespan_2_id
loop
v_result := timespan__overlaps_interval_p(
overlaps_p__timespan_1_id,
rec_timespan.interval_id
);
if v_result then
return true;
end if;
end loop;
return false;
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('timespan__overlaps_p','timespan_id,start_date;null,end_date;null');
--
-- procedure timespan__overlaps_p/3
--
--
-- Checks to see if interval with start and end dates overlap any of the intervals
-- in the timespan.
--
-- @author W. Scott Meeks
--
-- @param timespan_id Id of timespan as reference
-- @param start_date Start date of interval
-- @param end_date End date of interval
--
-- @return true if interval with start and end dates overlaps with second timespan, otherwise false.
--
CREATE OR REPLACE FUNCTION timespan__overlaps_p(
overlaps_p__timespan_id integer,
overlaps_p__start_date timestamptz, -- default null,
overlaps_p__end_date timestamptz -- default null
) RETURNS boolean AS $$
DECLARE
v_result boolean;
rec_timespan record;
BEGIN
-- Loop over each interval in timespan, checking against dates.
for rec_timespan in
select *
from timespans
where timespan_id = overlaps_p__timespan_id
loop
v_result := time_interval__overlaps_p(
rec_timespan.interval_id,
overlaps_p__start_date,
overlaps_p__end_date
);
if v_result then
return true;
end if;
end loop;
return false;
END;
$$ LANGUAGE plpgsql;
-- added
select define_function_args('timespan__copy','timespan_id,offset');
--
-- procedure timespan__copy/2
--
--
-- Creates a new copy of a timespan, offset by optional offset
-- JS: See note on intervals on time_interval__copy
--
-- @author W. Scott Meeks
--
-- @param timespan_id Timespan to copy
-- @param offset Offset al dates in timespan by this date interval
--
-- @return Id of copied timespan
--
CREATE OR REPLACE FUNCTION timespan__copy(
copy__timespan_id integer,
copy__offset interval -- default 0
) RETURNS integer AS $$
DECLARE
rec_timespan record;
v_interval_id timespans.interval_id%TYPE;
v_timespan_id timespans.timespan_id%TYPE;
BEGIN
v_timespan_id := null;
-- Loop over each interval in timespan, creating a new copy
for rec_timespan in
select *
from timespans
where timespan_id = copy__timespan_id
loop
v_interval_id := time_interval__copy(
rec_timespan.interval_id,
copy__offset
);
if v_timespan_id is null
then
-- JS: NOTE DEFAULT BEHAVIOR OF timespan__new
v_timespan_id := timespan__new(v_interval_id);
else
-- no copy, use whatever is generated by time_interval__copy
PERFORM timespan__join_interval(
v_timespan_id,
v_interval_id,
false);
end if;
end loop;
return v_timespan_id;
END;
$$ LANGUAGE plpgsql;
--
-- procedure timespan__copy/1
--
--
-- Creates a new copy of a timespan, no offset
--
-- @param timespan_id Timespan to copy
-- @param offset Offset al dates in timespan by this date interval
--
-- @return Id of copied timespan
--
CREATE OR REPLACE FUNCTION timespan__copy(
copy__timespan_id integer
) RETURNS integer AS $$
-- timespans.timespan_id%TYPE
DECLARE
BEGIN
return timespan__copy(
copy__timespan_id,
interval '0 days'
);
END;
$$ LANGUAGE plpgsql;
--
-- procedure timespan__copy/2
--
--
-- Creates a new copy of a timespan, offset by optional offset
-- JS: Overloaded function to make above compatible with Oracle behavior
-- JS: when an integer (for number of days) is supplied as a parameter.
--
-- @param timespan_id Timespan to copy
-- @param offset Offset all dates in timespan by this number of days
--
-- @return Id of copied timespan
--
CREATE OR REPLACE FUNCTION timespan__copy(
copy__timespan_id integer,
copy__offset integer
) RETURNS integer AS $$
DECLARE
BEGIN
return timespan__copy(
copy__timespan_id,
to_interval(copy__offset,'days')
);
END;
$$ LANGUAGE plpgsql;
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