Enum Value 

pub enum Value {
    Null(DataType),
    Integer(i64),
    Float(f64),
    Text(SmartString),
    Boolean(bool),
    Timestamp(DateTime<Utc>),
    Json(CompactArc<str>),
}

A runtime value with type information

Each variant carries its data directly, avoiding the need for interface indirection or separate value references.

Memory Layout (16 bytes)

Value is exactly 16 bytes due to niche optimization:

• Text(SmartString): 16 bytes with niches in tag byte (values 17-255 unused)
• Json(Arc): 8 bytes thin pointer with null niche
• Rust stores Value’s discriminant in these niche values

Note: Text uses SmartString for inline storage of strings up to 15 bytes. Longer strings use Arc for O(1) clone and sharing.

Variants

Null(DataType)

NULL value with optional type hint

Integer(i64)

64-bit signed integer

Float(f64)

64-bit floating point

Text(SmartString)

UTF-8 text string (SmartString: inline ≤15 bytes, Arc for larger)

Boolean(bool)

Boolean value

Timestamp(DateTime<Utc>)

Timestamp (UTC)

Json(CompactArc<str>)

JSON document (CompactArc for cheap cloning, 16-byte fat pointer)

Implementations

impl Value

pub fn null(data_type: DataType) -> Self

Create a NULL value with a type hint

pub fn null_unknown() -> Self

Create a NULL value with unknown type

pub fn integer(value: i64) -> Self

Create an integer value

pub fn float(value: f64) -> Self

Create a float value

pub fn text(value: impl Into<String>) -> Self

Create a text value

Uses SmartString::from_string_shared() for heap strings to enable O(1) clone via Arc. This allows string sharing between Arena, Index, and VersionStore.

pub fn text_arc(value: Arc<str>) -> Self

Create a text value from Arc (zero-copy for heap strings)

Preserves the Arc reference for O(1) clone and sharing.

pub fn boolean(value: bool) -> Self

Create a boolean value

pub fn timestamp(value: DateTime<Utc>) -> Self

Create a timestamp value

pub fn json(value: impl Into<String>) -> Self

Create a JSON value

pub fn json_arc(value: CompactArc<str>) -> Self

Create a JSON value from CompactArc (zero-copy)

pub fn data_type(&self) -> DataType

Returns the data type of this value

pub fn is_null(&self) -> bool

Returns true if this value is NULL

pub fn as_int64(&self) -> Option<i64>

Extract as i64, with type coercion

Returns None if:

• Value is NULL
• Conversion is not possible

pub fn as_float64(&self) -> Option<f64>

Extract as f64, with type coercion

pub fn as_boolean(&self) -> Option<bool>

Extract as boolean, with type coercion

pub fn as_string(&self) -> Option<String>

Extract as String, with type coercion

pub fn as_str(&self) -> Option<&str>

Extract as string reference (avoids clone for Text/Json)

pub fn as_arc_str(&self) -> Option<CompactArc<str>>

Extract as CompactArc (creates CompactArc for Text, cheap clone for Json)

pub fn as_timestamp(&self) -> Option<DateTime<Utc>>

Extract as DateTime

pub fn as_json(&self) -> Option<&str>

Extract as JSON string

pub fn compare(&self, other: &Value) -> Result<Ordering>

Compare two values for ordering

Returns:

• Ok(Ordering::Less) if self < other
• Ok(Ordering::Equal) if self == other
• Ok(Ordering::Greater) if self > other
• Err if comparison is not possible

pub fn from_typed(value: Option<&dyn Any>, data_type: DataType) -> Self

Create a Value from a typed value with explicit data type

pub fn coerce_to_type(&self, target_type: DataType) -> Value

Coerce this value to the target data type

Type coercion rules:

• Integer column receiving Float → converts to Integer
• Float column receiving Integer → converts to Float
• Text column receiving any type → converts to Text
• Timestamp column receiving String → parses timestamp
• JSON column receiving valid JSON string → stores as JSON
• Boolean column receiving Integer/String → converts to Boolean

Returns the coerced value, or NULL if coercion fails.

pub fn into_coerce_to_type(self, target_type: DataType) -> Value

Coerce value to target type, consuming self OPTIMIZATION: Avoids clone when types already match

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

Formats the value using the given formatter.

impl Default for Value

fn default() -> Self

Returns the “default value” for a type.

impl Display for Value

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

Formats the value using the given formatter.

impl From<&str> for Value

fn from(v: &str) -> Self

Converts to this type from the input type.

impl From<Arc<str>> for Value

fn from(v: Arc<str>) -> Self

Converts to this type from the input type.

impl From<DateTime<Utc>> for Value

fn from(v: DateTime<Utc>) -> Self

Converts to this type from the input type.

impl<T: Into<Value>> From<Option<T>> for Value

fn from(v: Option<T>) -> Self

Converts to this type from the input type.

impl From<String> for Value

fn from(v: String) -> Self

Converts to this type from the input type.

impl From<bool> for Value

fn from(v: bool) -> Self

Converts to this type from the input type.

impl From<f32> for Value

fn from(v: f32) -> Self

Converts to this type from the input type.

impl From<f64> for Value

fn from(v: f64) -> Self

Converts to this type from the input type.

impl From<i16> for Value

fn from(v: i16) -> Self

Converts to this type from the input type.

impl From<i32> for Value

fn from(v: i32) -> Self

Converts to this type from the input type.

impl From<i64> for Value

fn from(v: i64) -> Self

Converts to this type from the input type.

impl From<i8> for Value

fn from(v: i8) -> Self

Converts to this type from the input type.

impl From<u16> for Value

fn from(v: u16) -> Self

Converts to this type from the input type.

impl From<u32> for Value

fn from(v: u32) -> Self

Converts to this type from the input type.

impl From<u8> for Value

fn from(v: u8) -> Self

Converts to this type from the input type.

impl FromIterator<Value> for Row

fn from_iter<I: IntoIterator<Item = Value>>(iter: I) -> Self

Creates a value from an iterator.

impl FromValue for Value

fn from_value(value: &Value) -> Result<Self>

Convert a Value to Self

impl Hash for Value

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Value

Total ordering implementation for Value

This is required for using Value as a key in BTreeMap/BTreeSet. The ordering is defined as follows:

1. NULLs are always ordered first (smallest)
2. Numeric types (Integer, Float) are compared by numeric value (consistent with PartialEq)
3. Other different data types are ordered by their type discriminant
4. Same data types use their natural ordering

IMPORTANT: This ordering MUST be consistent with PartialEq. Since Integer(5) == Float(5.0) per PartialEq, we must ensure Integer(5).cmp(&Float(5.0)) == Ordering::Equal. Violating this contract causes BTreeMap corruption.

Note: This differs from SQL NULL semantics where NULL comparisons return UNKNOWN. This ordering is only for internal index structure.

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Value

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Value

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl ToParam for Value

fn to_param(&self) -> Value

Convert self into a Value for SQL parameter binding

impl Eq for Value