Database hits

Each operator will send a request to the storage engine to do work such as retrieving or updating data. A database hit (DBHits) is an abstract unit of this storage engine work.

These are all the actions that trigger one or more database hits:

  • Create actions

    • Create a node.

    • Create a relationship.

    • Create a new node label.

    • Create a new relationship type.

    • Create a new ID for property keys with the same name.

  • Delete actions

    • Delete a node.

    • Delete a relationship.

  • Update actions

    • Set one or more labels on a node.

    • Remove one or more labels from a node.

  • Node-specific actions

    • Get a node by its ID.

    • Get the degree of a node.

    • Determine whether a node is dense.

    • Determine whether a label is set on a node.

    • Get the labels of a node.

    • Get a property of a node.

    • Get an existing node label.

    • Get the name of a label by its ID, or its ID by its name.

  • Relationship-specific actions

    • Get a relationship by its ID.

    • Get a property of a relationship.

    • Get an existing relationship type.

    • Get a relationship type name by its ID, or its ID by its name.

  • General actions

    • Get the name of a property key by its ID, or its ID by the key name.

    • Find a node or relationship through an index seek or index scan.

    • Find a path in a variable-length expand.

    • Find a shortest path.

    • Ask the count store for a value.

  • Schema actions

    • Add an index.

    • Drop an index.

    • Get the reference of an index.

    • Create a constraint.

    • Drop a constraint.

  • Call a procedure.

  • Call a user-defined function.

The presented value can vary slightly depending on the Cypher® runtime that was used to execute the query. In the pipelined runtime the number of database hits will typically be higher since it uses a more accurate way of measuring.