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Module types

PostgreSQL data type OIDs and the extensible type codec registry.

Built-in OID constants (DataTypeOIDs)

Every PostgreSQL built-in type has a stable numeric OID. The DataTypeOIDs dict provides named constants so user code never needs to hard-code raw numbers:

import postgres { DataTypeOIDs }
echo DataTypeOIDs.Int4   # 23
echo DataTypeOIDs.Uuid   # 2950

Type codec registry (TypeRegistry)

The TypeRegistry maps OIDs to encoder / decoder function pairs. The singleton DefaultRegistry is pre-loaded with codecs for every type listed in the type-mapping table. Custom types can be registered with TypeRegistry.register().

import postgres { TypeRegistry }
# Register a custom "money" OID → Zuri number codec
TypeRegistry.register(790, @(buf) {   # decode binary → number
  return buf_to_int64(buf) / 100.0
}, @(value) {                          # encode number → binary
  return int64_to_buf(value * 100)
})

Variables

DataTypeOIDs

Named constants for every PostgreSQL built-in type OID that the library supports. Use these instead of raw integers in prepare() calls. Array-type OIDs follow the PostgreSQL convention of being the scalar OID minus a well-known offset; they are listed as <Type>Array.

DefaultRegistry

The shared default type registry used by all connections unless overridden. Mutate this to add global custom type support across the entire process.

Classes

class TypeRegistry

Registry that maps PostgreSQL type OIDs to binary encode / decode function pairs. A singleton instance (DefaultRegistry) is pre-populated with every built-in type listed in the type-mapping table. Call register() to add support for custom types, or to override the default behaviour of a built-in type.

Example — custom money type

import postgres { TypeRegistry }
TypeRegistry.register(
  790,
)

Methods

• TypeRegistry() (Constructor)

• register(oid, decoder, encoder)

  Registers a custom codec for the given OID.

  Parameters

  • number oid The PostgreSQL OID to handle.

  • function decoder @(buf_list) → value — binary → Zuri value.

  • function encoder @(value) → list — Zuri value → byte list.

• decode(buf, oid)

  Decodes a binary buffer buf (list of bytes) using the codec for oid. Returns nil if no decoder is registered for the OID (text fallback).

  Parameters

  • list buf Raw bytes from the PostgreSQL binary wire format.

  • number oid The PostgreSQL OID of the value.

• encode(value, oid)

  Encodes value to a byte list using the codec for oid.

  Parameters

  • any value The Zuri value to encode.

  • number oid The PostgreSQL OID for the target column / param.