PgHashingAttribute

Namespace: Ankus

Assembly: Ankus.Runtime.dll

Generates a PostgreSQL hash support function and default hash operator class from IPgHashable. Enum declarations hash their numeric value as eight little-endian bytes with PgHash.

[AttributeUsage(AttributeTargets.Class|AttributeTargets.Struct|AttributeTargets.Enum, Inherited = false)]
public sealed class PgHashingAttribute : Attribute

Requires PgType, PgEnum, or a readable PgDatumType mapping and a same-type equality operator, generated with PgEquality or declared with PgOperator. A mapped writer is not required. Non-enum types must implement IEquatable of the declared type and IPgHashable. Hashes must agree with equality and remain stable across processes, platforms and extension versions. Generated functions are strict, immutable and parallel safe. Changing the hashing contract requires rebuilding dependent indexes. Mapped readers must also provide stable, immutable and parallel-safe logical keys. Generated objects use the mapped SQL type’s schema; a fixed schema prevents extension relocation. PostgreSQL validates existing default classes and permissions, and resolves a domain’s default index class through its base type.

Inheritance: object, Attribute

Constructors

PgHashingAttribute()

public PgHashingAttribute()

Properties

GenerateSql

Gets or sets whether installation SQL is emitted for the hash operator family and class. The default is true. False retains the hash support function, equality prerequisite and dependency identifier. Cannot be false when Sql contains a replacement, including an empty string.

public bool GenerateSql { get; set; }

Value: bool

Id

Gets or sets the installation dependency identifier for the completed hash operator family and class.

public string? Id { get; set; }

Value: string

Requires

Gets or sets installation entities that must precede the generated hashing declarations.

public string[] Requires { get; set; }

Value: string[]

Sql

Gets or sets literal installation SQL replacing the hash operator family and class. Null preserves generated SQL; empty text emits no statements for this declaration.

public string? Sql { get; set; }

Value: string

@HASH_FUNCTION_SQL@ becomes the retained hash helper’s quoted SQL identifier, qualified when a fixed schema is declared, without an argument list. Do not add string quotes around this token. @MODULE_PATHNAME@ becomes MODULE_PATHNAME. The hash support function remains generated.

SqlRelocatable

Gets or sets whether the literal Sql replacement permits moving the extension to another schema. The default is false. This option applies only to non-null Sql; fixed schemas and other non-relocatable declarations can still prevent relocation.

public bool SqlRelocatable { get; set; }

Value: bool