Turning the page into a tutorial #506

lidiazuin · 2025-11-24T15:34:25Z

No description provided.

AlexicaWright

Nice rework!

modules/ROOT/pages/cypher/updating.adoc

AlexicaWright · 2025-11-24T16:00:57Z

modules/ROOT/pages/cypher/updating.adoc

-====
+== Delete properties
+
+Neo4j doesn't store null values, which means that if you set a property value as `null`, it will be automatically removed from your graph.


Suggested change

Neo4j doesn't store null values, which means that if you set a property value as `null`, it will be automatically removed from your graph.

To remove a property, either use the `REMOVE` clause, or set its value to `null`.

Neo4j doesn't store properties without values, so doing so removes the property from a node.

But even when you use REMOVE and then you MATCH it, you'll get null as value too. The sentence like that makes me understand that there's an option to literally remove the property, but it doesn't work like that

But this is explained a few lines further down, that the result of both operations is "Set 1 property".

AlexicaWright · 2025-11-25T12:57:05Z

modules/ROOT/pages/cypher/updating.adoc

+
+== Conclusion
+
+In this tutorial, you have seen how to update the information in your graph and avoid issues such as duplication or lack of information about when the changes were made.


Suggested change

In this tutorial, you have seen how to update the information in your graph and avoid issues such as duplication or lack of information about when the changes were made.

In this tutorial, you have seen how to update nodes, relationships, and properties.

You have also seen how to delete data from the graph as well as how to avoid duplication when adding new data.

Lacking information about when changes were made is not really an issue in most graphs, is it?

AlexicaWright · 2025-11-25T12:57:32Z

modules/ROOT/pages/cypher/updating.adoc

+|===
+| m | r | j
+
+| (:Person {twitter: "@mark", name: "Mark"})


Again, the twitter property was never added back after Mark's node was deleted.

AlexicaWright · 2025-11-25T12:59:08Z

modules/ROOT/pages/cypher/updating.adoc

-Earlier you learned how to represent nodes, relationships, labels, properties, and patterns in Cypher.
-This section adds another level to your knowledge by introducing how to update and delete data with Cypher.
+This tutorial shows how to update information in the graph by changing, removing, and adding nodes, relationships, and properties.
+It also addresses how to avoid duplication and how to keep track of changes by adding new properties to the graph.


I'm not sure the main purpose of using merge action clauses is to track change, so maybe consider changing the end of this sentence? I left a comment in the relevant section as well.

modules/ROOT/pages/cypher/updating.adoc

Co-authored-by: Jessica Wright <[email protected]>

AlexicaWright

Great update! A few more comments. I recommend to run the example queries. You can run them in Desktop, easy peasy and you don't need to set up an Aura account. Let me know if you have any questions!

modules/ROOT/pages/cypher/updating.adoc

AlexicaWright · 2025-11-27T14:32:44Z

modules/ROOT/pages/cypher/updating.adoc


-Notice that here `MATCH` is used to find both Mark's node and Jennifer's node before we use `MERGE` to find or create the relationship between them.
+Cypher can't find this pattern since Mark's node and all its relationships were deleted, and only their node was recreated.
+Consequently, if you use `CREATE` instead of `MERGE`, the whole pattern is created (with both nodes and the relationship), which results in duplicate nodes for `Jennifer` and `Mark`, but a new relationship.


MERGE recreates the whole pattern, regardless of whether any of the nodes existed already or not. So if you run this using CREATE instead, you still get the same result: two Mark nodes and one Jennifer node.
The point to make here is that you need to MATCH the nodes first and then use MERGE to recreate the relationship.

modules/ROOT/pages/cypher/updating.adoc

Co-authored-by: Jessica Wright <[email protected]>

AlexicaWright

I'm not getting the same results when I run the queries. I can create duplicates and no errors are thrown.

modules/ROOT/pages/cypher/updating.adoc

AlexicaWright · 2025-12-01T14:31:02Z

modules/ROOT/pages/cypher/updating.adoc

-To start, let us look at an example of this by adding Mark back to our database using the query below.
-You can use `MERGE` to ensure that Cypher checks the database for an existing node for Mark.
-Since you removed Mark's node in the previous examples, Cypher will not find an existing match and will create the node new with the `name` property set to 'Mark'.
+You won't get any results.


Yes you do, both queries yield the same results: Created 2 nodes, created 1 relationship, set 2 properties, added 2 labels. Duplicate Person nodes created and a new relationship between them added.

AlexicaWright · 2025-12-01T14:31:33Z

modules/ROOT/pages/cypher/updating.adoc

----
+--
+CREATE (mark:Person {name: 'Mark'})
+CREATE (jennifer:Person {name: 'Jennifer'})


You used Ann in the two examples above?

modules/ROOT/pages/cypher/updating.adoc

Co-authored-by: Jessica Wright <[email protected]>

AlexicaWright

Getting there! A few more comments, sorry ;)

modules/ROOT/pages/cypher/updating.adoc

AlexicaWright · 2025-12-02T08:53:58Z

modules/ROOT/pages/cypher/updating.adoc

+
+1+d|Rows: 1
+|===
+


You had a great explanation of the difference between CREATE and MERGE before. I think you should keep that and place it here. It could be useful with a little summary of when to use which and why.

modules/ROOT/pages/cypher/updating.adoc

AlexicaWright · 2025-12-02T09:04:31Z

modules/ROOT/pages/cypher/updating.adoc

+If you run the same statement again, using `CREATE`, you will create another duplication.
+But if you use `MERGE`, Cypher only finds the now existing node.


Suggested change

If you run the same statement again, using `CREATE`, you will create another duplication.

But if you use `MERGE`, Cypher only finds the now existing node.

This has already been covered above.

modules/ROOT/pages/cypher/updating.adoc

AlexicaWright · 2025-12-02T09:11:13Z

modules/ROOT/pages/cypher/updating.adoc

-====

-=== Handling _MERGE_ criteria
+`MATCH` finds both Mark and Ann's node before `MERGE` (finds or) creates the relationship between them.


You can use CREATE here, it doesn't matter as long as there is no relationship already. What matters is that you MATCH Ann and Mark first and then use their variables in the MERGE clause. That's what avoids the duplication. I think we need to be clear about that.

Co-authored-by: Jessica Wright <[email protected]>

AlexicaWright · 2025-12-04T10:06:02Z

modules/ROOT/pages/cypher/updating.adoc

+--

-*Query result:*
+Cypher returns the existing node without creating a new one:


Maybe there should be an example adding Jennifer back using merge to show what MERGE does? You had an explanation in there before, but if you don't want to put that back, I think we need to showcase that MERGE looks for the node/pattern and if it doesn't exist, creates it.
So using MERGE with Ann's node shows that there was a match so no creation of a new node, and using MERGE with Jennifer's node could show that when there is no match (since we deleted her in the previous example), a node is created. WDYT?

modules/ROOT/pages/cypher/updating.adoc

Co-authored-by: Jessica Wright <[email protected]>

AlexicaWright

Just one last comment. Promise! It looks really good!

modules/ROOT/pages/cypher/updating.adoc

Co-authored-by: Jessica Wright <[email protected]>

AlexicaWright

APPROVE!!!

neo4j-docops-agent · 2025-12-04T12:28:48Z

Thanks for the documentation updates.

The preview documentation has now been torn down - reopening this PR will republish it.

* Turning the page into a tutorial * Apply suggestions from code review Co-authored-by: Jessica Wright <[email protected]> * updates after review * Apply suggestions from code review Co-authored-by: Jessica Wright <[email protected]> * updates after review and testing * Apply suggestions from code review Co-authored-by: Jessica Wright <[email protected]> * updates after review * Apply suggestions from code review Co-authored-by: Jessica Wright <[email protected]> * fixes after review * Apply suggestions from code review Co-authored-by: Jessica Wright <[email protected]> * update after review * Update modules/ROOT/pages/cypher/updating.adoc Co-authored-by: Jessica Wright <[email protected]> --------- Co-authored-by: Jessica Wright <[email protected]>

* Turning the page into a tutorial * Apply suggestions from code review * updates after review * Apply suggestions from code review * updates after review and testing * Apply suggestions from code review * updates after review * Apply suggestions from code review * fixes after review * Apply suggestions from code review * update after review * Update modules/ROOT/pages/cypher/updating.adoc --------- Co-authored-by: Jessica Wright <[email protected]>

Turning the page into a tutorial

32e5635

lidiazuin added the cherry-pick this forward label Nov 24, 2025

AlexicaWright reviewed Nov 25, 2025

View reviewed changes

lidiazuin and others added 2 commits November 25, 2025 16:37

Apply suggestions from code review

9c3f717

Co-authored-by: Jessica Wright <[email protected]>

updates after review

8cd09fb

lidiazuin requested a review from AlexicaWright November 27, 2025 13:17

AlexicaWright reviewed Nov 27, 2025

View reviewed changes

lidiazuin and others added 3 commits November 27, 2025 15:51

Apply suggestions from code review

ffa9bf6

Co-authored-by: Jessica Wright <[email protected]>

Merge branch 'dev' into cypherupdate

fe6c950

updates after review and testing

2e42a50

AlexicaWright reviewed Dec 1, 2025

View reviewed changes

lidiazuin and others added 2 commits December 1, 2025 16:49

Apply suggestions from code review

1f9ed8b

Co-authored-by: Jessica Wright <[email protected]>

updates after review

9334f31

AlexicaWright reviewed Dec 2, 2025

View reviewed changes

lidiazuin and others added 2 commits December 2, 2025 12:05

Apply suggestions from code review

7cd46f1

Co-authored-by: Jessica Wright <[email protected]>

fixes after review

7cf61b3

AlexicaWright reviewed Dec 4, 2025

View reviewed changes

lidiazuin and others added 2 commits December 4, 2025 13:08

Apply suggestions from code review

8581ef7

Co-authored-by: Jessica Wright <[email protected]>

update after review

480611b

AlexicaWright reviewed Dec 4, 2025

View reviewed changes

modules/ROOT/pages/cypher/updating.adoc Outdated Show resolved Hide resolved

Update modules/ROOT/pages/cypher/updating.adoc

cc6f0a3

Co-authored-by: Jessica Wright <[email protected]>

AlexicaWright approved these changes Dec 4, 2025

View reviewed changes

lidiazuin merged commit 252db14 into neo4j:dev Dec 4, 2025
5 checks passed

lidiazuin deleted the cypherupdate branch December 4, 2025 12:30

lidiazuin mentioned this pull request Dec 4, 2025

Turning the page into a tutorial (#506) #510

Merged

	Neo4j doesn't store null values, which means that if you set a property value as `null`, it will be automatically removed from your graph.
	To remove a property, either use the `REMOVE` clause, or set its value to `null`.
	Neo4j doesn't store properties without values, so doing so removes the property from a node.


		== Conclusion

		In this tutorial, you have seen how to update the information in your graph and avoid issues such as duplication or lack of information about when the changes were made.

	In this tutorial, you have seen how to update the information in your graph and avoid issues such as duplication or lack of information about when the changes were made.
	In this tutorial, you have seen how to update nodes, relationships, and properties.
	You have also seen how to delete data from the graph as well as how to avoid duplication when adding new data.

		If you run the same statement again, using `CREATE`, you will create another duplication.
		But if you use `MERGE`, Cypher only finds the now existing node.


		1+d\|Rows: 1
		\|===

Turning the page into a tutorial #506

Turning the page into a tutorial #506

Uh oh!

Conversation

lidiazuin commented Nov 24, 2025

Uh oh!

AlexicaWright left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

AlexicaWright left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Uh oh!

AlexicaWright left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

AlexicaWright left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

AlexicaWright left a comment

Choose a reason for hiding this comment

neo4j-docops-agent commented Dec 4, 2025 •

edited

Loading