SQL - UPDATE EDGE

Updates edge records in the current database. This is the equivalent of the UPDATE command, with the addition of checking and maintaining graph consistency with vertices, in the event that you update the out and in properties.

Bear in mind that OrientDB can also work in schema-less mode, allowing you to create fields on the fly. Furthermore, that it works on collections and necessarily includes some extensions to the standard SQL for handling collections.

This command was introduced in version 2.2.

Syntax

UPDATE EDGE <edge> 
  [SET|INCREMENT|ADD|REMOVE|PUT <field-name> = <field-value>[,]*]|[CONTENT|MERGE <JSON>]
  [UPSERT]
  [RETURN <returning> [<returning-expression>]]
  [WHERE <conditions>]
  [LOCK default|record]
  [LIMIT <max-records>] [TIMEOUT <timeout>]
  • <edge> Defines the edge that you want to update. You can choose between:
    • Class Updating edges by class.
    • Cluster Updating edges by cluster, using CLUSTER prefix.
    • Record ID Updating edges by Record ID.
  • SET Updates the field to the given value.
  • REMOVE Defines an item to remove from a collection of fields.
  • RETURN Defines the expression you want to return after running the update.
    • COUNT Returns the number of updated records. This is the default operator.
    • BEFORE Returns the records before the update.
    • AFTER Returns the records after the update.
  • WHERE Defines the filter conditions.
  • LOCK Defines how the record locks between the load and update. You can choose between the following lock strategies:
    • DEFAULT Disables locking. Use this in the event of concurrent updates. It throws an exception in the event of conflict.
    • RECORD Locks the record during the update.
  • UPSERT Updates a record if it exists or inserts a new record if it doesn't. This avoids the need to execute two commands, (one for each condition, inserting and updating).
  • LIMIT Defines the maximum number of records to update.

Examples

  • Change the edge endpoint:

    orientdb> UPDATE EDGE Friend SET out = (SELECT FROM Person WHERE name = 'John') 
              WHERE foo = 'bar'
    

    Limitations of the UPSERT Clause

The UPSERT clause only guarantees atomicity when you use a UNIQUE index and perform the look-up on the index through the WHERE condition.

orientdb> UPDATE EDGE hasAssignee SET foo = 'bar' UPSERT WHERE id = 56

Here, you must have a unique index on id to guarantee uniqueness on concurrent operations.

For more information, see

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