compiler: Standard Cypher constructions

[szarnyasg]

(Related ticket: #51)

Use this issue to keep track of supported Cypher constructs.

Clauses

• Pattern matching constructs
  • node pattern
  • relationship pattern of a single hop
  • relationship pattern of multiple hops
  • direction of the relationship pattern
  • attribute constraints in node and relationship patterns
• Data manipulation
  • CREATE
  • MERGE
  • SET
  • DELETE
  • DETACH DELETE
  • REMOVE
• Procedure calls
  • CALL ... YIELD (as this call may run an arbitrary Java code, there is no way we can handle these incrementally)

Sub-clauses

We can safely ignore these for now.

• ON CREATE
• ON MATCH

Operators

• String operations
  • STARTS WITH
  • CONTAINS
  • ENDS WITH
• Query constructs
  • MATCH
    • Sub-clause:
      • WHERE
    • MATCH, without OPTIONAL
    • OPTIONAL MATCH
      • as non-first MATCH clause of a single query
      • as first MATCH clause of a single query, see Support OPTIONAL MATCH as the first MATCH clause of a query #40
  • RETURN
    • RETURN *
    • expression on the return list
    • alias handling
    • RETURN DISTINCT
    • Sub-clauses:
      • ORDER BY (handles variables and expressions as well as name resolution for aliased RETURN items)
      • SKIP (SKIP and LIMIT only implemented for constants)
      • LIMIT
  • UNWIND
  • WITH
    • Sub-clause:
      • WHERE Handle WITH...WHERE subclause #124
  • UNION
• Arithmetic comparison
  • =
  • <> (also !=, though non-standard)
  • <
  • >
  • <=
  • >=
• Arithmetic operators
  • +
  • -
  • /
  • *
  • ^
  • %
• Logical operators
  • NOT
  • AND
  • OR
  • XOR
• NULLs
  • <variable> IS [NOT] NULL
  • <expression> IS [NOT] NULL
• Accessors
  • . (property access)
  • [] (subscript) (Note: we don't support p['foo'], which is a syntax sugar for p.foo)

Expressions

• Parameters with new syntax ($)
• Literals
• Aggregation functions
  • avg()
  • collect()
  • count()
  • max()
  • min()
  • sum()
• Statistical functions
  • stdDev()
  • stdDevP()

We can safely ignore these for now:

• List comprehensions
• Pattern comprehensions

Functions

• Predicate functions
  • exists()
• Scalar functions
  • coalesce()
  • endNode()
  • head()
  • length()
  • last()
  • properties()
  • size()
  • startNode()
  • type()
  • toFloat()
• List functions
  • relationships()
  • tail()
  • keys()
  • labels()
  • nodes()
  • range()
• Numeric functions
  • abs()
  • ceil()
  • floor()
  • rand()
  • round()
  • sign()
• Logarithmic functions
  • e()
  • exp()
  • log()
  • log10()
  • sqrt()
• Trigonometric functions
  • acos()
  • asin()
  • atan()
  • atan2()
  • cos()
  • cot()
  • degrees()
  • pi()
  • radians()
  • sin()
  • tan()
• String functions
  • left()
  • lTrim()
  • trim()
  • replace()
  • reverse()
  • right()
  • rTrim()
  • split()
  • substring()
  • toLower()
  • toString()
  • toUpper()
• Statistical functions
  • percentileCont()
  • percentileDisc()
• Not included in Cypher:
  • toBoolean()
  • toInteger() (called toInt())

Types

• primitives
• list
• map
• node
• relationship
• path

[szarnyasg]

We have quite a few constructs ready - the rest goes for DBPL and beyond.

[szarnyasg]

Let's continue this in #150, #151 and #152.