diff --git a/expected/35_no_gaps_timestamp_test.out b/expected/35_no_gaps_timestamp_test.out
new file mode 100644
index 0000000..b0d9503
--- /dev/null
+++ b/expected/35_no_gaps_timestamp_test.out
@@ -0,0 +1,253 @@
+CREATE TABLE timestamp_shifts (
+  job_id INTEGER,
+  worker_id INTEGER,
+  valid_from TIMESTAMP,
+  valid_to TIMESTAMP
+);
+-- Add era and unique key via sql_saga
+SELECT sql_saga.add_era('timestamp_shifts', 'valid_from', 'valid_to');
+ add_era 
+---------
+ t
+(1 row)
+
+SELECT sql_saga.add_unique_key('timestamp_shifts', ARRAY['job_id', 'worker_id']);
+             add_unique_key              
+-----------------------------------------
+ timestamp_shifts_job_id_worker_id_valid
+(1 row)
+
+TABLE sql_saga.era;
+    table_name    | era_name | start_column_name | end_column_name | range_type |   bounds_check_constraint    | audit_table_name 
+------------------+----------+-------------------+-----------------+------------+------------------------------+------------------
+ date_shifts      | valid    | valid_from        | valid_to        | daterange  | date_shifts_valid_check      | 
+ timestamp_shifts | valid    | valid_from        | valid_to        | tsrange    | timestamp_shifts_valid_check | 
+(2 rows)
+
+TABLE sql_saga.unique_keys;
+                key_name                 |    table_name    |    column_names    | era_name |                     unique_constraint                     |               exclude_constraint               
+-----------------------------------------+------------------+--------------------+----------+-----------------------------------------------------------+------------------------------------------------
+ date_shifts_job_id_worker_id_valid      | date_shifts      | {job_id,worker_id} | valid    | date_shifts_job_id_worker_id_valid_from_valid_to_key      | date_shifts_job_id_worker_id_daterange_excl
+ timestamp_shifts_job_id_worker_id_valid | timestamp_shifts | {job_id,worker_id} | valid    | timestamp_shifts_job_id_worker_id_valid_from_valid_to_key | timestamp_shifts_job_id_worker_id_tsrange_excl
+(2 rows)
+
+INSERT INTO timestamp_shifts(job_id, worker_id, valid_from, valid_to) VALUES
+  (1, 1, '2017-11-27 06:00:00', '2017-11-27 12:00:00'),
+  (1, 2, '2017-11-27 12:00:00', '2017-11-27 17:00:00'),
+  (2, 3, '2017-11-27 06:00:00', '2017-11-27 12:00:00'),
+  (2, 4, '2017-11-27 13:00:00', '2017-11-27 17:00:00'),
+  (3, 5, '-infinity',           '2017-11-27 12:00:00'),
+  (3, 5, '2017-11-27 12:00:00', '2017-11-27 17:00:00'),
+  (4, 6, '2017-11-27 06:00:00', '2017-11-27 12:00:00'),
+  (4, 7, '2017-11-27 12:00:00', 'infinity')
+;
+-- TRUE:
+-- it covers when the range matches one exactly:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 12:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+ no_gaps 
+---------
+ t
+(1 row)
+
+-- it covers when the range matches two exactly:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+ no_gaps 
+---------
+ t
+(1 row)
+
+-- it covers when the range has extra in front:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 08:00:00', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+ no_gaps 
+---------
+ t
+(1 row)
+
+-- it covers when the range has extra behind:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 14:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+ no_gaps 
+---------
+ t
+(1 row)
+
+-- it covers when the range has extra on both sides:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 08:00:00', '2017-11-27 14:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+ no_gaps 
+---------
+ t
+(1 row)
+
+-- an infinite start will cover a finite target:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 3;
+ no_gaps 
+---------
+ t
+(1 row)
+
+-- an infinite start will cover an infinite target:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('-infinity', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 3;
+ no_gaps 
+---------
+ t
+(1 row)
+
+-- an infinite end will cover a finite target:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 4;
+ no_gaps 
+---------
+ t
+(1 row)
+
+-- an infinite end will cover an infinite target:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', 'infinity'))
+FROM    timestamp_shifts
+WHERE   job_id = 4;
+ no_gaps 
+---------
+ t
+(1 row)
+
+-- FALSE:
+-- it does not cover when the range is null:
+SELECT  sql_saga.no_gaps(NULL, tstzrange('2017-11-27 08:00:00', '2017-11-27 14:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+ no_gaps 
+---------
+ f
+(1 row)
+
+-- it does not cover when the range misses completely:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-29 08:00:00', '2017-11-29 14:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+ no_gaps 
+---------
+ f
+(1 row)
+
+-- it does not cover when the range has something at the beginning:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 04:00:00', '2017-11-27 14:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+ no_gaps 
+---------
+ f
+(1 row)
+
+-- it does not cover when the range has something at the end:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 20:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+ no_gaps 
+---------
+ f
+(1 row)
+
+-- it does not cover when the range has something in the middle:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 2;
+ no_gaps 
+---------
+ f
+(1 row)
+
+-- it does not cover when the range is lower-unbounded:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('-infinity', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+ no_gaps 
+---------
+ f
+(1 row)
+
+-- it does not cover when the range is upper-unbounded:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', 'infinity'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+ no_gaps 
+---------
+ f
+(1 row)
+
+-- it does not cover when the range is both-sides-unbounded:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('-infinity', 'infinity'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+ no_gaps 
+---------
+ f
+(1 row)
+
+-- an infinite start will not cover a finite target if there is uncovered time at the end:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 20:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 3;
+ no_gaps 
+---------
+ f
+(1 row)
+
+-- an infinite start will not cover an infinite target if there is uncovered time at the end:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('-infinity', '2017-11-27 20:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 3;
+ no_gaps 
+---------
+ f
+(1 row)
+
+-- an infinite end will not cover a finite target if there is uncovered time at the beginning:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 03:00:00', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 4;
+ no_gaps 
+---------
+ f
+(1 row)
+
+-- an infinite end will not cover an infinite target if there is uncovered time at the beginning:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 03:00:00', 'infinity'))
+FROM    timestamp_shifts
+WHERE   job_id = 4;
+ no_gaps 
+---------
+ f
+(1 row)
+
+-- NULL:
+-- it is unknown when the target is null:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), null)
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+ no_gaps 
+---------
+ 
+(1 row)
+
+-- Errors:
+-- it fails if the input ranges go backwards:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 13:00:00', '2017-11-27 20:00:00') ORDER BY worker_id DESC)
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+ERROR:  no_gaps first argument should be sorted but got a range ending before the last covered_to
+-- TODO: handle an empty target range? e.g. [5, 5)
+-- Or maybe since that is a self-contradiction maybe ignore that case?
+DELETE FROM timestamp_shifts;
diff --git a/sql/35_no_gaps_timestamp_test.sql b/sql/35_no_gaps_timestamp_test.sql
new file mode 100644
index 0000000..681c632
--- /dev/null
+++ b/sql/35_no_gaps_timestamp_test.sql
@@ -0,0 +1,152 @@
+CREATE TABLE timestamp_shifts (
+  job_id INTEGER,
+  worker_id INTEGER,
+  valid_from TIMESTAMP,
+  valid_to TIMESTAMP
+);
+-- Add era and unique key via sql_saga
+SELECT sql_saga.add_era('timestamp_shifts', 'valid_from', 'valid_to');
+SELECT sql_saga.add_unique_key('timestamp_shifts', ARRAY['job_id', 'worker_id']);
+
+TABLE sql_saga.era;
+TABLE sql_saga.unique_keys;
+
+INSERT INTO timestamp_shifts(job_id, worker_id, valid_from, valid_to) VALUES
+  (1, 1, '2017-11-27 06:00:00', '2017-11-27 12:00:00'),
+  (1, 2, '2017-11-27 12:00:00', '2017-11-27 17:00:00'),
+  (2, 3, '2017-11-27 06:00:00', '2017-11-27 12:00:00'),
+  (2, 4, '2017-11-27 13:00:00', '2017-11-27 17:00:00'),
+  (3, 5, '-infinity',           '2017-11-27 12:00:00'),
+  (3, 5, '2017-11-27 12:00:00', '2017-11-27 17:00:00'),
+  (4, 6, '2017-11-27 06:00:00', '2017-11-27 12:00:00'),
+  (4, 7, '2017-11-27 12:00:00', 'infinity')
+;
+
+-- TRUE:
+
+-- it covers when the range matches one exactly:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 12:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+
+-- it covers when the range matches two exactly:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+
+-- it covers when the range has extra in front:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 08:00:00', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+
+-- it covers when the range has extra behind:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 14:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+
+-- it covers when the range has extra on both sides:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 08:00:00', '2017-11-27 14:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+
+-- an infinite start will cover a finite target:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 3;
+
+-- an infinite start will cover an infinite target:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('-infinity', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 3;
+
+-- an infinite end will cover a finite target:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 4;
+
+-- an infinite end will cover an infinite target:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', 'infinity'))
+FROM    timestamp_shifts
+WHERE   job_id = 4;
+
+-- FALSE:
+
+-- it does not cover when the range is null:
+SELECT  sql_saga.no_gaps(NULL, tstzrange('2017-11-27 08:00:00', '2017-11-27 14:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+
+-- it does not cover when the range misses completely:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-29 08:00:00', '2017-11-29 14:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+
+-- it does not cover when the range has something at the beginning:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 04:00:00', '2017-11-27 14:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+
+-- it does not cover when the range has something at the end:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 20:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+
+-- it does not cover when the range has something in the middle:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 2;
+
+-- it does not cover when the range is lower-unbounded:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('-infinity', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+
+-- it does not cover when the range is upper-unbounded:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', 'infinity'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+
+-- it does not cover when the range is both-sides-unbounded:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('-infinity', 'infinity'))
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+
+-- an infinite start will not cover a finite target if there is uncovered time at the end:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 06:00:00', '2017-11-27 20:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 3;
+
+-- an infinite start will not cover an infinite target if there is uncovered time at the end:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('-infinity', '2017-11-27 20:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 3;
+
+-- an infinite end will not cover a finite target if there is uncovered time at the beginning:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 03:00:00', '2017-11-27 17:00:00'))
+FROM    timestamp_shifts
+WHERE   job_id = 4;
+
+-- an infinite end will not cover an infinite target if there is uncovered time at the beginning:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 03:00:00', 'infinity'))
+FROM    timestamp_shifts
+WHERE   job_id = 4;
+
+
+-- NULL:
+
+-- it is unknown when the target is null:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), null)
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+
+-- Errors:
+
+-- it fails if the input ranges go backwards:
+SELECT  sql_saga.no_gaps(tstzrange(valid_from,valid_to), tstzrange('2017-11-27 13:00:00', '2017-11-27 20:00:00') ORDER BY worker_id DESC)
+FROM    timestamp_shifts
+WHERE   job_id = 1;
+
+-- TODO: handle an empty target range? e.g. [5, 5)
+-- Or maybe since that is a self-contradiction maybe ignore that case?
+
+DELETE FROM timestamp_shifts;