See for an overview of range types. shows the specialized operators available for range types. shows the specialized operators available for multirange types. In addition to those, the usual comparison operators shown in are available for range and multirange types. The comparison operators order first by the range lower bounds, and only if those are equal do they compare the upper bounds. The multirange operators compare each range until one is unequal. This does not usually result in a useful overall ordering, but the operators are provided to allow unique indexes to be constructed on ranges. Operator Description Example(s) anyrange @> anyrange boolean Does the first range contain the second? int4range(2,4) @> int4range(2,3) t anyrange @> anyelement boolean Does the range contain the element? '[2011-01-01,2011-03-01)'::tsrange @> '2011-01-10'::timestamp t anyrange <@ anyrange boolean Is the first range contained by the second? int4range(2,4) <@ int4range(1,7) t anyelement <@ anyrange boolean Is the element contained in the range? 42 <@ int4range(1,7) f anyrange && anyrange boolean Do the ranges overlap, that is, have any elements in common? int8range(3,7) && int8range(4,12) t anyrange << anyrange boolean Is the first range strictly left of the second? int8range(1,10) << int8range(100,110) t anyrange >> anyrange boolean Is the first range strictly right of the second? int8range(50,60) >> int8range(20,30) t anyrange &< anyrange boolean Does the first range not extend to the right of the second? int8range(1,20) &< int8range(18,20) t anyrange &> anyrange boolean Does the first range not extend to the left of the second? int8range(7,20) &> int8range(5,10) t anyrange -|- anyrange boolean Are the ranges adjacent? numrange(1.1,2.2) -|- numrange(2.2,3.3) t anyrange + anyrange anyrange Computes the union of the ranges. The ranges must overlap or be adjacent, so that the union is a single range (but see range_merge()). numrange(5,15) + numrange(10,20) [5,20) anyrange * anyrange anyrange Computes the intersection of the ranges. int8range(5,15) * int8range(10,20) [10,15) anyrange - anyrange anyrange Computes the difference of the ranges. The second range must not be contained in the first in such a way that the difference would not be a single range. int8range(5,15) - int8range(10,20) [5,10) Operator Description Example(s) anymultirange @> anymultirange boolean Does the first multirange contain the second? '{[2,4)}'::int4multirange @> '{[2,3)}'::int4multirange t anymultirange @> anyrange boolean Does the multirange contain the range? '{[2,4)}'::int4multirange @> int4range(2,3) t anymultirange @> anyelement boolean Does the multirange contain the element? '{[2011-01-01,2011-03-01)}'::tsmultirange @> '2011-01-10'::timestamp t anyrange @> anymultirange boolean Does the range contain the multirange? '[2,4)'::int4range @> '{[2,3)}'::int4multirange t anymultirange <@ anymultirange boolean Is the first multirange contained by the second? '{[2,4)}'::int4multirange <@ '{[1,7)}'::int4multirange t anymultirange <@ anyrange boolean Is the multirange contained by the range? '{[2,4)}'::int4multirange <@ int4range(1,7) t anyrange <@ anymultirange boolean Is the range contained by the multirange? int4range(2,4) <@ '{[1,7)}'::int4multirange t anyelement <@ anymultirange boolean Is the element contained by the multirange? 4 <@ '{[1,7)}'::int4multirange t anymultirange && anymultirange boolean Do the multiranges overlap, that is, have any elements in common? '{[3,7)}'::int8multirange && '{[4,12)}'::int8multirange t anymultirange && anyrange boolean Does the multirange overlap the range? '{[3,7)}'::int8multirange && int8range(4,12) t anyrange && anymultirange boolean Does the range overlap the multirange? int8range(3,7) && '{[4,12)}'::int8multirange t anymultirange << anymultirange boolean Is the first multirange strictly left of the second? '{[1,10)}'::int8multirange << '{[100,110)}'::int8multirange t anymultirange << anyrange boolean Is the multirange strictly left of the range? '{[1,10)}'::int8multirange << int8range(100,110) t anyrange << anymultirange boolean Is the range strictly left of the multirange? int8range(1,10) << '{[100,110)}'::int8multirange t anymultirange >> anymultirange boolean Is the first multirange strictly right of the second? '{[50,60)}'::int8multirange >> '{[20,30)}'::int8multirange t anymultirange >> anyrange boolean Is the multirange strictly right of the range? '{[50,60)}'::int8multirange >> int8range(20,30) t anyrange >> anymultirange boolean Is the range strictly right of the multirange? int8range(50,60) >> '{[20,30)}'::int8multirange t anymultirange &< anymultirange boolean Does the first multirange not extend to the right of the second? '{[1,20)}'::int8multirange &< '{[18,20)}'::int8multirange t anymultirange &< anyrange boolean Does the multirange not extend to the right of the range? '{[1,20)}'::int8multirange &< int8range(18,20) t anyrange &< anymultirange boolean Does the range not extend to the right of the multirange? int8range(1,20) &< '{[18,20)}'::int8multirange t anymultirange &> anymultirange boolean Does the first multirange not extend to the left of the second? '{[7,20)}'::int8multirange &> '{[5,10)}'::int8multirange t anymultirange &> anyrange boolean Does the multirange not extend to the left of the range? '{[7,20)}'::int8multirange &> int8range(5,10) t anyrange &> anymultirange boolean Does the range not extend to the left of the multirange? int8range(7,20) &> '{[5,10)}'::int8multirange t anymultirange -|- anymultirange boolean Are the multiranges adjacent? '{[1.1,2.2)}'::nummultirange -|- '{[2.2,3.3)}'::nummultirange t anymultirange -|- anyrange boolean Is the multirange adjacent to the range? '{[1.1,2.2)}'::nummultirange -|- numrange(2.2,3.3) t anyrange -|- anymultirange boolean Is the range adjacent to the multirange? numrange(1.1,2.2) -|- '{[2.2,3.3)}'::nummultirange t anymultirange + anymultirange anymultirange Computes the union of the multiranges. The multiranges need not overlap or be adjacent. '{[5,10)}'::nummultirange + '{[15,20)}'::nummultirange {[5,10), [15,20)} anymultirange * anymultirange anymultirange Computes the intersection of the multiranges. '{[5,15)}'::int8multirange * '{[10,20)}'::int8multirange {[10,15)} anymultirange - anymultirange anymultirange Computes the difference of the multiranges. '{[5,20)}'::int8multirange - '{[10,15)}'::int8multirange {[5,10), [15,20)} The left-of/right-of/adjacent operators always return false when an empty range or multirange is involved; that is, an empty range is not considered to be either before or after any other range. Elsewhere empty ranges and multiranges are treated as the additive identity: anything unioned with an empty value is itself. Anything minus an empty value is itself. An empty multirange has exactly the same points as an empty range. Every range contains the empty range. Every multirange contains as many empty ranges as you like. The range union and difference operators will fail if the resulting range would need to contain two disjoint sub-ranges, as such a range cannot be represented. There are separate operators for union and difference that take multirange parameters and return a multirange, and they do not fail even if their arguments are disjoint. So if you need a union or difference operation for ranges that may be disjoint, you can avoid errors by first casting your ranges to multiranges. shows the functions available for use with range types. shows the functions available for use with multirange types. Function Description Example(s) lower lower ( anyrange ) anyelement Extracts the lower bound of the range (NULL if the range is empty or has no lower bound). lower(numrange(1.1,2.2)) 1.1 upper upper ( anyrange ) anyelement Extracts the upper bound of the range (NULL if the range is empty or has no upper bound). upper(numrange(1.1,2.2)) 2.2 isempty isempty ( anyrange ) boolean Is the range empty? isempty(numrange(1.1,2.2)) f lower_inc lower_inc ( anyrange ) boolean Is the range's lower bound inclusive? lower_inc(numrange(1.1,2.2)) t upper_inc upper_inc ( anyrange ) boolean Is the range's upper bound inclusive? upper_inc(numrange(1.1,2.2)) f lower_inf lower_inf ( anyrange ) boolean Does the range have no lower bound? (A lower bound of -Infinity returns false.) lower_inf('(,)'::daterange) t upper_inf upper_inf ( anyrange ) boolean Does the range have no upper bound? (An upper bound of Infinity returns false.) upper_inf('(,)'::daterange) t range_merge range_merge ( anyrange, anyrange ) anyrange Computes the smallest range that includes both of the given ranges. range_merge('[1,2)'::int4range, '[3,4)'::int4range) [1,4) Function Description Example(s) lower lower ( anymultirange ) anyelement Extracts the lower bound of the multirange (NULL if the multirange is empty or has no lower bound). lower('{[1.1,2.2)}'::nummultirange) 1.1 upper upper ( anymultirange ) anyelement Extracts the upper bound of the multirange (NULL if the multirange is empty or has no upper bound). upper('{[1.1,2.2)}'::nummultirange) 2.2 isempty isempty ( anymultirange ) boolean Is the multirange empty? isempty('{[1.1,2.2)}'::nummultirange) f lower_inc lower_inc ( anymultirange ) boolean Is the multirange's lower bound inclusive? lower_inc('{[1.1,2.2)}'::nummultirange) t upper_inc upper_inc ( anymultirange ) boolean Is the multirange's upper bound inclusive? upper_inc('{[1.1,2.2)}'::nummultirange) f lower_inf lower_inf ( anymultirange ) boolean Does the multirange have no lower bound? (A lower bound of -Infinity returns false.) lower_inf('{(,)}'::datemultirange) t upper_inf upper_inf ( anymultirange ) boolean Does the multirange have no upper bound? (An upper bound of Infinity returns false.) upper_inf('{(,)}'::datemultirange) t range_merge range_merge ( anymultirange ) anyrange Computes the smallest range that includes the entire multirange. range_merge('{[1,2), [3,4)}'::int4multirange) [1,4) multirange (function) multirange ( anyrange ) anymultirange Returns a multirange containing just the given range. multirange('[1,2)'::int4range) {[1,2)} unnest for multirange unnest ( anymultirange ) setof anyrange Expands a multirange into a set of ranges in ascending order. unnest('{[1,2), [3,4)}'::int4multirange) [1,2) [3,4) The lower_inc, upper_inc, lower_inf, and upper_inf functions all return false for an empty range or multirange.