Not a path pattern expression #1431
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This PR includes documentation updates New pages: Updated pages: |
Lojjs
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Really nice new content, just some minor feedback
| 2+d|Rows: 5 | ||
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| When '<exp>', then the label expression predicate results in `null`, e.g. if `p` is `null`, then `p:!CEO` results in `null`. |
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It feels like something is missing here, it should not say just When '<exp>' right?
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| CYPHER 25 | ||
| MATCH ()-[r]->(p:Person) | ||
| UNWIND labels(p) AS label | ||
| FILTER label <> "Person" | ||
| RETURN COLLECT(label) AS managerLabels | ||
| NEXT | ||
| MATCH (p) | ||
| RETURN p.name AS name, p:$any(managerLabels) AS isManager | ||
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| 2+d|Rows: 5 | ||
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| If `r` is `null`, then the label expression predicate, e.g. `r:WORKS_FOR|REPORTS_TO` results in `null`. |
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Perhaps you should add the sentence about using coalesce to change nulls to default values here as well. Having read the whole page it is clear, but if someone is looking at this example only it might be a bit confusing that this sentence mentions null and the result below does not
| RETURN employee.name AS employee, (p:Person) AS workForAPeron | ||
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| The above query has the same result as teh query that used `p:Person` in stead of `(p:Person)`: |
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| The above query has the same result as teh query that used `p:Person` in stead of `(p:Person)`: | |
| The above query has the same result as the query that used `p:Person` instead of `(p:Person)`: |
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| MATCH (employee:Person)-[:WORKS_FOR]->(p) | ||
| WHERE p:Person | ||
| RETURN employee.name AS employee, p:Person AS workForAPeron |
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| RETURN employee.name AS employee, p:Person AS workForAPeron | |
| RETURN employee.name AS employee, p:Person AS workForAPerson |
| .Result | ||
| [role="queryresult",options="header,footer",cols="2*<m"] | ||
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| | employee | workForAPeron |
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| | employee | workForAPeron | |
| | employee | workForAPerson |
| [source, error] | ||
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| Invalid input 'Node' for `p`. Expected to be Boolean. | ||
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Not necessary for this PR, but we should maybe think about starting to use the GQL errors in the Cypher manual instead.
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This adds some documentation about potential confusion of some parenthesized expression with path pattern expressions.
While doing so, I could not find documentation of the label expression predicate, so I add some too.
The new SVG, is a manually edit copy of another. I do not have an SVG editor handy, so I was a bit limited. If you have better tools feel free to adjust, of course.
Fixes SURF-165