Enum Value 

pub enum Value {
    Int(i64),
    Float(f64),
    Str(String),
    Bool(bool),
    List(Vec<Value>),
    Map(BTreeMap<String, Value>),
    Date(i32),
    LocalDateTime(i64),
    DateTime {
        micros_utc: i64,
        offset_seconds: i32,
    },
    Duration {
        months: i32,
        days: i32,
        nanos: i64,
    },
    Binary(Vec<u8>),
    Null,
}

A property or query value.

Serde tags are a storage format

bincode encodes a variant by its declaration index, and the WAL, the mixed-column blob and snapshots all store Value that way. A variant is therefore only ever added, never reordered or removed, and a new storable variant goes before Null, which is always last. The index of every variant is pinned by types::tests::value_serde_tags_are_pinned; changing it means changing that test deliberately.

Variants

Int(i64)

Float(f64)

Str(String)

Bool(bool)

List(Vec<Value>)

Map(BTreeMap<String, Value>)

Nested key-value map. Spills to the Mixed column path like List. Never promotes a homogeneous typed column. Not fulltext-indexed.

Date(i32)

Calendar date: days since 1970-01-01. JSON form {"$date": "2024-01-15"}.

LocalDateTime(i64)

Date and time with no time zone: microseconds since 1970-01-01T00:00:00. JSON form {"$ldt": "2024-01-15T12:34:56.789012"}.

DateTime

An instant plus the UTC offset it was written with. The offset is kept so the value prints back as written; equality and ordering in queries and in index keys use micros_utc only. A valid offset is within ±18:00 (MAX_OFFSET_SECONDS). JSON form {"$dt": "2024-01-15T12:34:56.789012+05:30"}.

Fields

micros_utc: i64

offset_seconds: i32

Duration

openCypher duration: months, days and nanoseconds are independent and never normalized against each other (a month is not 30 days). Not totally ordered. JSON form {"$dur": "P1Y2M3DT4H5M6.789S"}.

Fields

months: i32

days: i32

nanos: i64

Binary(Vec<u8>)

Byte blob, no encoding assumed. JSON form {"$binary": "<base64>"}.

Null

Null as an element of a list or a value of a map, produced only by query evaluation ([1, null], {a: n.missing}). A top-level query null is still Option<Value>::None.

Query-only: it is never stored. The write path refuses a property value that holds one, and the WAL frame and column encoders refuse it again as a backstop. It serialises like any unit variant (bincode tag = its index; serde JSON "Null"), so a query result carrying it can be sent anywhere a Value can.

Must stay the last variant. Add new variants above it.

Implementations

impl Value

pub fn contains_null(&self) -> bool

True if this value is Value::Null or holds one at any depth. A write path refuses such a value: a stored property can never be null.

Trait Implementations

impl Clone for Value

fn clone(&self) -> Value

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Value

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Value

fn deserialize<__D>( __deserializer: __D, ) -> Result<Value, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for Value

fn eq(&self, other: &Value) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for Value

fn serialize<__S>( &self, __serializer: __S, ) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Value