Expand description
Fundamental data representation.
This module contains the types for representing data in Materialize that all layers of the stack can understand. Think of it as the lingua franca: individual layers may use different representations internally, but they all agree to use this representation at their boundaries.
- The core value type is the
Datum
enum, which represents a literal value. Row
extends aDatum
horizontally, and has features for efficiently doing so.RelationDesc
describes what it takes to extend aRow
vertically, and corresponds most closely to what is returned from querying our dataflows
Re-exports
pub use crate::global_id::GlobalId;
Modules
- Abstract data types.
- A re-useable vector of
Datum
with varying lifetimes. - diff 🔒
- A set of traits for modeling things that can be explained by a SQL
EXPLAIN
statement. - Provides fixed-length representations for data composed of
Datum
s of fixed-length types. These representations are aimed at being more efficient in memory usage thanRow
by relying on statically selected container lengths. Traits are provided that allow these representations to be made into instances ofRow
or created fromRow
s. The traits are trivially implemented forRow
itself, providing a uniform interface to describeRow
s or fixed-length containers standing in for them. - Namespace constants to share between high- and low-levels of the system.
- relation 🔒
- row 🔒
- scalar 🔒
- Routines for converting datum values to and from their string representation.
- Custom Protobuf types for the
url
crate.
Structs
- The name of a column in a
RelationDesc
. - The type of a
Datum
. - A sequence of Datums
- A mapping from string keys to Datums
- A re-useable vector of
Datum
with no particular lifetime. - A borrowed allocation of
Datum
with a specific lifetime. - Expression violated not-null constraint on named column
- A description of the shape of a relation.
- The type of a relation.
- A packed representation for
Datum
s. RowArena
is used to hold on to temporaryRow
s for functions likeeval
that need to create complexDatum
s but don’t have aRow
to put them in yet.- An implementation of PartDecoder for Row.
- An implementation of PartEncoder for Row.
- Packs datums into a
Row
. - A wrapper around a byte slice that guarantees the data are row-formatted.
- A thread-local row, which can be borrowed and returned.
- System-wide timestamp type.
Enums
Traits
- Types that implement this trait can be stored in an SQL column with the specified ColumnType
- An
enum_dispatch
companion forDatumDecoder
. - An
enum_dispatch
companion forDatumEncoder
. FnOnce<T: DatumToPersist>() -> R
- A bridge between native Rust types and SQL runtime types represented in Datums
Functions
- Generate an arbitrary
PropDatum
. - Number of bytes required by a list of datums. This computes the size that would be required if the given datums were packed into a list.
- Number of bytes required by the datum. This is used to optimistically pre-allocate buffers for packing rows.
- Number of bytes required by a sequence of datums.
- This returns true if we don’t care to keep stats for this column type (for now). We’ll have to remove this if/when we start actually using the schema’d part encoding.
- Return the number of bytes these Datums would use if packed as a Row.
Type Aliases
- System-wide record count difference type.