Neo4j CQL

 

Cypher Query Language Commands

Neo4j Read CQL Clauses

1. MATCH
• This clause is used to search the data with a specified pattern.
• Syntax: Match (n)
2. OPTIONAL MATCH
• This is the same as match
• The only difference being it can use nulls in case of missing parts of the pattern.
3. WHERE
• This clause id is used to add contents to the CQL queries.
4. START
• This clause is used to find the starting points through the legacy indexes.
5. LOAD CSV
• This clause is used to import data from CSV files.

Neo4j Write CQL Clauses

1. CREATE
• This clause is used to create nodes, relationships, and properties.
2. MERGE
• This clause verifies whether the specified pattern exists in the graph. If not, it creates the pattern.
3. SET
• This clause is used to update labels on nodes, properties on nodes and relationships.
4. DELETE
• This clause is used to delete nodes and relationships or paths etc. from the graph.
5. REMOVE
• This clause is used to remove properties and elements from nodes and relationships.
6. FOREACH
• This class is used to update the data within a list.
7. CREATE UNIQUE
• Using the clauses CREATE and MATCH, you can get a unique pattern by matching the existing pattern and creating the missing one.

Neo4j General CQL Clauses

1. RETURN
• This clause is used to define what to include in the query result set.
2. ORDER BY
• This clause is used to arrange the output of a query in order. It is used along with the clauses RETURN or WITH.
3. LIMIT
• This clause is used to limit the rows in the result to a specific value.
4. SKIP
• This clause is used to define from which row to start including the rows in the output.
5. WITH
• This clause is used to chain the query parts together.
6. UNWIND
• This clause is used to expand a list into a sequence of rows.
7. UNION
• This clause is used to combine the result of multiple queries.
8. CALL
• This clause is used to invoke a procedure deployed in the database.

Operators in Cypher Query Language

• Mathematical +, -, *, /, %, ^
• Comparison +, <>, <, >, <=, >=
• Boolean AND, OR, XOR, NOT
• String +
• List +, IN, [X], [X…..Y]
• Regular Expression =-
• String matching STARTS WITH, ENDS WITH, CONSTRAINTS