Clauses
This section contains information on all the clauses in the Cypher® query language.
Reading clauses
These comprise clauses that read data from the database.
The flow of data within a Cypher query is an unordered sequence of maps with key-value pairs — a set of possible bindings between the variables in the query and values derived from the database. This set is refined and augmented by subsequent parts of the query.
Clause | Description |
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Specify the patterns to search for in the database. |
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Specify the patterns to search for in the database while using |
Projecting clauses
These comprise clauses that define which expressions to return in the result set.
The returned expressions may all be aliased using AS
.
Clause | Description |
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Defines what to include in the query result set. |
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Allows query parts to be chained together, piping the results from one to be used as starting points or criteria in the next. |
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Expands a list into a sequence of rows. |
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Defines a query to have no result. |
Reading sub-clauses
These comprise sub-clauses that must operate as part of reading clauses.
Sub-clause | Description |
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Adds constraints to the patterns in a |
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A sub-clause following |
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Defines from which row to start including the rows in the output. As of Neo4j 5.24, it can be used as a standalone clause. |
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Constrains the number of rows in the output. As of Neo4j 5.24, it can be used as a standalone clause. |
Writing clauses
These comprise clauses that write the data to the database.
Clause | Description |
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Create nodes and relationships. |
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Delete nodes, relationships or paths. Any node to be deleted must also have all associated relationships explicitly deleted. |
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Delete a node or set of nodes. All associated relationships will automatically be deleted. |
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Update labels on nodes and properties on nodes and relationships. |
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Remove properties and labels from nodes and relationships. |
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Update data within a list, whether components of a path, or the result of aggregation. |
Reading/Writing clauses
These comprise clauses that both read data from and write data to the database.
Clause | Description |
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Ensures that a pattern exists in the graph. Either the pattern already exists, or it needs to be created. |
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Used in conjunction with |
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Used in conjunction with |
Invokes a procedure deployed in the database and return any results. |
Subquery clauses
Clause | Description |
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Evaluates a subquery, typically used for post-union processing or aggregations. |
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Evaluates a subquery in separate transactions. Typically used when modifying or importing large amounts of data. |
Multiple graphs
Clause | Description |
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Determines which graph a query, or query part, is executed against. Fabric |
Importing data
Clause | Description |
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Use when importing data from CSV files. |
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This clause may be used to prevent an out-of-memory error from occurring when importing large amounts of data using |
Listing functions and procedures
Clause | Description |
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List the available functions. |
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List the available procedures. |
Transaction Commands
Clause | Description |
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List the available transactions. |
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Terminate transactions by their IDs. |
Reading hints
These comprise clauses used to specify planner hints when tuning a query. More details regarding the usage of these — and query tuning in general — can be found in Planner hints and the USING keyword.
Hint | Description |
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Index hints are used to specify which index, if any, the planner should use as a starting point. |
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Index seek hint instructs the planner to use an index seek for this clause. |
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Scan hints are used to force the planner to do a label scan (followed by a filtering operation) instead of using an index. |
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Join hints are used to enforce a join operation at specified points. |
Index and constraint clauses
These comprise clauses to create, show, and drop indexes and constraints.
Clause | Description |
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Create, show or drop an index. |
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Create, show or drop a constraint. |