PostgreSQL analogies

This page describes range types, functions and operators in PostgreSQL, and what their Spans equivalents are.

Range types

Most range types included in Spans have an equivalent in PostgreSQL.

Postgresql type Python type
int4range intrange
int8range intrange
numrange floatrange, though floatrange does not accept integers
tsrange datetimerange
tstzrange datetimerange
daterange daterange
Does not exist [1] timedeltarange
Does not exist strrange

Operators

Most operators are not overloaded in Python to their PostgreSQL equivalents. Instead Spans implements the functionality using methods.

Operator PostgreSQL Python
Equal a = b a == b
Not equal a != b or a <> b a != b
Less than a < b a < b
Greater than a > b a > b
Less than or equal a < b a < b
Greater than or equal a > b a > b
Contains a @> b a.contains(b)
Is contained by a <@ b a in b or a.within(b)
Overlap a && b a.overlap(b)
Strictly left of a << b a.left_of(b) or a << b
Strictly right of a >> b a.right_of(b) or a >> b
Does not extend to the right of a &< b a.endsbefore(b)
Does not extend to the left of a &> b a.startsafter(b)
Is adjacent to a -|- b a.adjacent(b)
Union a + b a.union(b) or a | b
Intersection a * b a.intersection(b) or a & b
Difference a - b a.difference(b) or a - b

Functions

There are no functions in Spans that operate on ranges. Instead they are implemented as methods, properties or very simple combinations.

PostgreSQL function Python equivalent
lower(a) a.lower
upper(a) a.upper
isempty(a) a.upper
lower_inc(a) a.lower_inc
upper_inc(a) a.upper_inc
lower_inf(a) a.lower_inf
upper_inf(a) a.upper_inf
range_merge(a) intrangeset([a, b]).span()
[1]Though it is not built in it can be created using: CREATE TYPE intervalrange AS RANGE(SUBTYPE = interval);