Cypher III (function, schema)

function

2. Predicates (assertion)
   
   
   1. All syntax
      　ALL(identifier in collection WHERE predicate)
      　　
   2. Any (at least one), None,single (exactly one)
   3. exist syntax
      　 EXISTS( pattern-or-property )
4. Scalar (scalar)
   
   
   1. COALESCE (,,,) (consolidated)
      Returns NULL if the first non-null value is NULL
   2. Head (x)
      Returns the first node, last with the opposite
   3. ToInt (string or float, etc.)
      Failure returns null
6. Collection
   
   
   1. NODES (PATH)
      Return all nodes on the path
   2. Relationships (PATH)
   3. LABELS (node)
   4. KEYS (Property-container)
      
   5. EXTRACT (identifier in collection | expression)
      
   6. FILTER (identifier in collection WHERE predicate)
   7. TAIL (expression)
      Return all except the first one.
   8. RANGE (Start, end [, step])
   9. REDUCE (accumulator = initial, identifier in collection | expression)
      Accumulator Saving Results
      　　
8. Mathematical functions
   
   
   1. ATAN2 (max) = PI/4 (range-pi to pi (not including-PI)
   2. Semi-positive vector function haversinθ=versinθ/2= (1-cosθ)/2
   3. RADIANS (expression) angle to radians
   4. RAND ()
   5. sign (expression) takes a symbol
10. String
    
    
    1. RETURN Str (1), str ("Hello")
       Add quotation marks to both ends
    2. Replace (original, search, replace)
    3. SUBSTRING (original, start [, length])
    4. Left (original, length) returns a substring
    5. SPLIT (original, Splitpattern)
    6. REVERSE (original)
    7. TOSTRING (expression) Note the difference from STR

Schema

1. Index
   
   
   1. CREATE INDEX on:P erson (name)
   2. DROP INDEX on:P erson (name)
2. Constraint
   　
   
   1. The unique in Cypher two has explained
   2. exist constraints
      CREATE CONSTRAINT ON (book:Book) ASSERT exists(book.isbn)
DROP CONSTRAINT ON (book:Book) ASSERT exists(book.isbn)　　

Execution plans

1. Starting point operators
   
2. Expand operators
   
3. Combining operators
   
4. Row operators
   
5. Update Operators
   

Cypher Three (function, schema)