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new 7cda962 Fixed formatting in Comparability Section
7cda962 is described below
commit 7cda9625e316f4f99a7b79321ad4fd64b74e6565
Author: Josh Innis <[email protected]>
AuthorDate: Fri Oct 22 04:39:06 2021 -0700
Fixed formatting in Comparability Section
---
docs/intro/comparability.md | 23 ++++-------------------
1 file changed, 4 insertions(+), 19 deletions(-)
diff --git a/docs/intro/comparability.md b/docs/intro/comparability.md
index 7b5b268..f99d104 100644
--- a/docs/intro/comparability.md
+++ b/docs/intro/comparability.md
@@ -8,16 +8,12 @@ AGE already has good semantics for equality within the
primitive types (booleans
* ORDER BY will not fail if the values passed to it have different types.
The underlying conceptual model is complex and sometimes inconsistent. This
leads to an unclear relationship between comparison operators, equality,
grouping, and ORDER BY:
-
-
-
* Comparability and orderability are aligned with each other consistently, as
all types can be ordered and compared.
* The difference between equality and equivalence, as exposed by IN, =,
DISTINCT, and grouping, in AGE is limited to testing two instances of the value
null to each other
* In equality, null = null is null.
* In equivalence, used by DISTINCT and when grouping values, two null
values are always treated as being the same value.
* However, equality treats null values differently if they are an element
of a list or a map value.
-
## Concepts
The openCypher specification features four distinct concepts related to
equality and ordering:
@@ -25,22 +21,22 @@ The openCypher specification features four distinct
concepts related to equality
### Comparability
- Comparability is used by the inequality operators (>, <, >=, <=),
and defines the underlying semantics of how to compare two values.
+Comparability is used by the inequality operators (>, <, >=, <=), and
defines the underlying semantics of how to compare two values.
### Equality
- Equality is used by the equality operators (=, <>), and the list
membership operator (IN). It defines the underlying semantics to determine if
two values are the same in these contexts. Equality is also used implicitly by
literal maps in node and relationship patterns, since such literal maps are
merely a shorthand notation for equality predicates.
+Equality is used by the equality operators (=, <>), and the list membership
operator (IN). It defines the underlying semantics to determine if two values
are the same in these contexts. Equality is also used implicitly by literal
maps in node and relationship patterns, since such literal maps are merely a
shorthand notation for equality predicates.
### Orderability
- Orderability is used by the ORDER BY clause, and defines the underlying
semantics of how to order values.
+Orderability is used by the ORDER BY clause, and defines the underlying
semantics of how to order values.
### Equivalence
- Equivalence is used by the DISTINCT modifier and by grouping in projection
clauses (WITH,RETURN), and defines the underlying semantics to determine if two
values are the same in these contexts.
+Equivalence is used by the DISTINCT modifier and by grouping in projection
clauses (WITH,RETURN), and defines the underlying semantics to determine if two
values are the same in these contexts.
## Comparability and equality
@@ -53,8 +49,6 @@ Unfortunately, it may not be possible to implement separate
comparison operators
Comparability is defined between any pair of values, as specified below.
-
-
* Numbers
* Numbers of different types (excluding NaN values and the Infinities) are
compared to each other as if both numbers would have been coerced to arbitrary
precision big decimals(currently outside the Cypher type system) before
comparing them with each other numerically in ascending order.
* Comparison to any value that is not also Number follows the rules of
orderability.
@@ -83,9 +77,6 @@ Comparability is defined between any pair of values, as
specified below.
* Comparison to any value that is not also a regular map follows the rules
of orderability.
Entities
-
-
-
* Vertices
* The comparison order for vertices is based on the assigned graphid.
* Edges
@@ -93,8 +84,6 @@ Entities
* Paths
* Paths are compared as if they were a list of alternating nodes and
relationships of the path from the start node to the end node. For example,
given nodes n1, n2, n3, and relationships r1and r2, and given that n1 < n2
< n3 and r1 < r2, then the path p1 from n1 to n3 via r1 would be less
than the path p2 to n1 from n2 via r2.
* Expressed in terms of lists:
-
- ```
```
p1 < p2
<=> [n1, r1, n3] < [n1, r2, n2]
@@ -104,8 +93,6 @@ p1 < p2
<=> true || (false && false)
<=> true
```
-
-
* Comparison to any value that is not also a path will return false.
* NULL
* null is incomparable with any other value (including other null values.)
@@ -115,8 +102,6 @@ p1 < p2
The ordering of different Agtype, when using <, <=, >, >= from smallest
value to largest value is:
-
-
1. Edge
2. Path
3. Map
