Range Functions and Operators

Range Operators

• =

  Description: Equals

  Example:

  MogDB=# SELECT int4range(1,5) = '[1,4]'::int4range AS RESULT;
   result
  --------
   t
  (1 row)

• <>

  Description: Does not equal to

  Example:

  MogDB=# SELECT numrange(1.1,2.2) <> numrange(1.1,2.3) AS RESULT;
   result
  --------
   t
  (1 row)

• <

  Description: Is less than

  Example:

  MogDB=# SELECT int4range(1,10) < int4range(2,3) AS RESULT;
   result
  --------
   t
  (1 row)

• >

  Description: Is greater than

  Example:

  MogDB=# SELECT int4range(1,10) > int4range(1,5) AS RESULT;
   result
  --------
   t
  (1 row)

• <=

  Description: Is less than or equals

  Example:

  MogDB=# SELECT numrange(1.1,2.2) <= numrange(1.1,2.2) AS RESULT;
   result
  --------
   t
  (1 row)

• >=

  Description: Is greater than or equals

  Example:

  MogDB=# SELECT numrange(1.1,2.2) >= numrange(1.1,2.0) AS RESULT;
   result
  --------
   t
  (1 row)

• @>

  Description: Contains ranges

  Example:

  MogDB=# SELECT int4range(2,4) @> int4range(2,3) AS RESULT;
   result
  --------
   t
  (1 row)

• @>

  Description: Contains elements

  Example:

  MogDB=# SELECT '[2011-01-01,2011-03-01)'::tsrange @> '2011-01-10'::timestamp AS RESULT;
   result
  --------
   t
  (1 row)

• <@

  Description: Range is contained by

  Example:

  MogDB=# SELECT int4range(2,4) <@ int4range(1,7) AS RESULT;
   result
  --------
   t
  (1 row)

• <@

  Description: Element is contained by

  Example:

  MogDB=# SELECT 42 <@ int4range(1,7) AS RESULT;
   result
  --------
   f
  (1 row)

• &&

  Description: Overlap (have points in common)

  Example:

  MogDB=# SELECT int8range(3,7) && int8range(4,12) AS RESULT;
   result
  --------
   t
  (1 row)

• <<

  Description: Strictly left of

  Example:

  MogDB=# SELECT int8range(1,10) << int8range(100,110) AS RESULT;
   result
  --------
   t
  (1 row)

• >>

  Description: Strictly right of

  Example:

  MogDB=# SELECT int8range(50,60) >> int8range(20,30) AS RESULT;
   result
  --------
   t
  (1 row)

• &<

  Description: Does not extend to the right of

  Example:

  MogDB=# SELECT int8range(1,20) &< int8range(18,20) AS RESULT;
   result
  --------
   t
  (1 row)

• &>

  Description: Does not extend to the left of

  Example:

  MogDB=# SELECT int8range(7,20) &> int8range(5,10) AS RESULT;
   result
  --------
   t
  (1 row)

• -|-

  Description: Is adjacent to

  Example:

  MogDB=# SELECT numrange(1.1,2.2) -|- numrange(2.2,3.3) AS RESULT;
   result
  --------
   t
  (1 row)

• +

  Description: Union

  Example:

  MogDB=# SELECT numrange(5,15) + numrange(10,20) AS RESULT;
   result
  --------
   [5,20)
  (1 row)

• *

  Description: Intersection

  Example:

  MogDB=# SELECT int8range(5,15) * int8range(10,20) AS RESULT;
   result
  ---------
   [10,15)
  (1 row)

• -

  Description: Difference

  Example:

  MogDB=# SELECT int8range(5,15) - int8range(10,20) AS RESULT;
   result
  --------
   [5,10)
  (1 row)

The simple comparison operators <, >, <=, and >= compare the lower bounds first, and only if those are equal, compare the upper bounds.

The <<, >>, and -|- operators always return false when an empty range is involved; that is, an empty range is not considered to be either before or after any other range.

The union and difference operators will fail if the resulting range would need to contain two disjoint sub-ranges.

Range Functions

• numrange(numeric, numeric, [text])

  Description: Specifies a range.

  Return type: Range's element type

  Example:

  MogDB=# SELECT numrange(1.1,2.2) AS RESULT;
   result
  --------
  [1.1,2.2)
  (1 row)
  MogDB=# SELECT numrange(1.1,2.2, '()') AS RESULT;
   result
  --------
  (1.1,2.2)
  (1 row)

• lower(anyrange)

  Description: Lower bound of a range

  Return type: Range's element type

  Example:

  MogDB=# SELECT lower(numrange(1.1,2.2)) AS RESULT;
   result
  --------
      1.1
  (1 row)

• upper(anyrange)

  Description: Upper bound of a range

  Return type: Range's element type

  Example:

  MogDB=# SELECT upper(numrange(1.1,2.2)) AS RESULT;
   result
  --------
      2.2
  (1 row)

• isempty(anyrange)

  Description: Is the range empty?

  Return type: Boolean

  Example:

  MogDB=# SELECT isempty(numrange(1.1,2.2)) AS RESULT;
   result
  --------
   f
  (1 row)

• lower_inc(anyrange)

  Description: Is the lower bound inclusive?

  Return type: Boolean

  Example:

  MogDB=# SELECT lower_inc(numrange(1.1,2.2)) AS RESULT;
   result
  --------
   t
  (1 row)

• upper_inc(anyrange)

  Description: Is the upper bound inclusive?

  Return type: Boolean

  Example:

  MogDB=# SELECT upper_inc(numrange(1.1,2.2)) AS RESULT;
   result
  --------
   f
  (1 row)

• lower_inf(anyrange)

  Description: Is the lower bound infinite?

  Return type: Boolean

  Example:

  MogDB=# SELECT lower_inf('(,)'::daterange) AS RESULT;
   result
  --------
   t
  (1 row)

• upper_inf(anyrange)

  Description: Is the upper bound infinite?

  Return type: Boolean

  Example:

  MogDB=# SELECT upper_inf('(,)'::daterange) AS RESULT;
   result
  --------
   t
  (1 row)

The lower and upper functions return null if the range is empty or the requested bound is infinite. The lower_inc, upper_inc, lower_inf, and upper_inf functions all return false for an empty range.

• elem_contained_by_range(anyelement, anyrange)

  Description: Determines whether an element is within the range.

  Return type: Boolean

  Example:

  MogDB=# SELECT elem_contained_by_range('2', numrange(1.1,2.2));
   elem_contained_by_range
  -------------------------
   t
  (1 row)