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Jul 20, 2022
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Escape comparative operators (#3) #4

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2 changes: 1 addition & 1 deletion modules/ROOT/pages/clauses/where.adoc
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Expand Up @@ -770,7 +770,7 @@ The name and age values for nodes that have name `'Peter'` but no belt property
[[simple-range]]
=== Simple range

To check for an element being inside a specific range, use the inequality operators `<`, `\<=`, `>=`, `>`.
To check for an element being inside a specific range, use the inequality operators `+<+`, `+<=+`, `+>=+`, `+>+`.

.Query
[source, cypher, indent=0]
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23 changes: 12 additions & 11 deletions modules/ROOT/pages/syntax/operators.adoc
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Expand Up @@ -53,7 +53,7 @@ This section contains an overview of operators.
| xref::syntax/operators.adoc#query-operators-aggregation[Aggregation operators] | `DISTINCT`
| xref::syntax/operators.adoc#query-operators-property[Property operators] | `.` for static property access, `[]` for dynamic property access, `=` for replacing all properties, `+=` for mutating specific properties
| xref::syntax/operators.adoc#query-operators-mathematical[Mathematical operators] | `+`, `-`, `*`, `/`, `%`, `^`
| xref::syntax/operators.adoc#query-operators-comparison[Comparison operators] | `=`, `<>`, `<`, `>`, `+<=+`, `>=`, `IS NULL`, `IS NOT NULL`
| xref::syntax/operators.adoc#query-operators-comparison[Comparison operators] | `+=+`, `+<>+`, `+<+`, `+>+`, `+<=+`, `+>=+`, `IS NULL`, `IS NOT NULL`
| xref::syntax/operators.adoc#query-operators-comparison[String-specific comparison operators] | `STARTS WITH`, `ENDS WITH`, `CONTAINS`
| xref::syntax/operators.adoc#query-operators-boolean[Boolean operators] | `AND`, `OR`, `XOR`, `NOT`
| xref::syntax/operators.adoc#query-operators-string[String operators] | `+` for concatenation, `=~` for regex matching
Expand Down Expand Up @@ -292,12 +292,12 @@ RETURN b - a AS result

The comparison operators comprise:

* equality: `=`
* inequality: `<>`
* less than: `<`
* greater than: `>`
* less than or equal to: `\<=`
* greater than or equal to: `>=`
* equality: `+=+`
* inequality: `+<>+`
* less than: `+<+`
* greater than: `+>+`
* less than or equal to: `+<=+`
* greater than or equal to: `+>=+`
* `IS NULL`
* `IS NOT NULL`

Expand Down Expand Up @@ -385,11 +385,11 @@ It is an error to compare values that cannot be compared.
[[cypher-ordering]]
=== Ordering and comparison of values

The comparison operators `\<=`, `<` (for ascending) and `>=`, `>` (for descending) are used to compare values for ordering.
The comparison operators `+<=+`, `+<+` (for ascending) and `+>=+`, `+>+` (for descending) are used to compare values for ordering.
The following points give some details on how the comparison is performed.

* Numerical values are compared for ordering using numerical order (e.g. `3 < 4` is true).
* All comparability tests (<, <=, >, >=) with `java.lang.Double.NaN` evaluate as false.
* All comparability tests (`+<+`, `+<=+`, `+>+`, `+>=+`) with `java.lang.Double.NaN` evaluate as false.
For example, `1 > b` and `1 < b` are both false when b is NaN.
* String values are compared for ordering using lexicographic order (e.g. `"x" < "xy"`).
* Boolean values are compared for ordering such that `false < true`.
Expand Down Expand Up @@ -448,9 +448,10 @@ For example, `[1, 'foo', 3]` is ordered before `[1, 2, 'bar']` since `'foo'` is

[[cypher-operations-chaining]]
=== Chaining comparison operations
Comparisons can be chained arbitrarily, e.g., `x < y \<= z` is equivalent to `x < y AND y \<= z`.

Formally, if `a, b, c, \..., y, z` are expressions and `op1, op2, \..., opN` are comparison operators, then `a op1 b op2 c \... y opN z` is equivalent to `a op1 b and b op2 c and \... y opN z`.
Comparisons can be chained arbitrarily, e.g., `+x < y <= z+` is equivalent to `+x < y AND y <= z+`.

Formally, if `+a, b, c, ..., y, z+` are expressions and `+op1, op2, ..., opN+` are comparison operators, then `+a op1 b op2 c ... y opN z+` is equivalent to `+a op1 b and b op2 c and ... y opN z+`.

Note that `a op1 b op2 c` does not imply any kind of comparison between `a` and `c`, so that, e.g., `x < y > z` is perfectly legal (although perhaps not elegant).

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2 changes: 1 addition & 1 deletion modules/ROOT/pages/syntax/spatial.adoc
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Expand Up @@ -262,7 +262,7 @@ xref::query-tuning/indexes.adoc#administration-indexes-spatial-distance-searches
== Comparability and orderability

The comparability and orderability of spacial values are due to change in an upcoming future release.
This means that queries that rely on the comparison of two points using the inequality operators, `<`, `+<=+`, `>`, and `>=`, or the specific order of an `ORDER BY n.point` query will need to be rewritten.
This means that queries that rely on the comparison of two points using the inequality operators, `+<+`, `+<=+`, `+>+`, and `+>=+`, or the specific order of an `ORDER BY n.point` query will need to be rewritten.

The most efficient way to do this is to explicitly specify the ordering. For example, by using `point.x`, `point.y` in _cartesian coordinates_, or `point.longitude` and `point.latitude` in _geographic coordinates_.