r"""Google Cloud Spanner PostgreSQL-interface dialect ("Spangres").
Extends the Postgres dialect with the Spanner PostgreSQL-interface DDL
extensions: ``INTERLEAVE IN [PARENT]`` for interleaved tables and ``TTL
INTERVAL ... ON`` for row-level time-to-live. The GoogleSQL ``ROW DELETION
POLICY`` form is accepted on parse and normalized to the canonical policy
node so generation always emits the valid PostgreSQL-dialect ``TTL`` form.
"""
from typing import TYPE_CHECKING, Any
from sqlglot.dialects.postgres import Postgres
from sqlspec.dialects.spanner._generators import SpangresGenerator
from sqlspec.dialects.spanner._parsers import SpangresParser, attach_hints
if TYPE_CHECKING:
from sqlglot import exp
__all__ = ("Spangres",)
[docs]
class Spangres(Postgres):
"""Spanner PostgreSQL-compatible dialect."""
Parser = SpangresParser
Generator = SpangresGenerator
[docs]
def parse(self, sql: str, **opts: Any) -> "list[exp.Expr | None]":
"""Parse Spangres SQL statements and attach hints."""
expressions = super().parse(sql, **opts)
for expression in expressions:
if expression is not None:
attach_hints(expression)
return expressions
[docs]
def parse_into(self, expression_type: Any, sql: str, **opts: Any) -> "list[exp.Expr | None]":
"""Parse into specific expression type with attached hints."""
expressions = super().parse_into(expression_type, sql, **opts)
for expression in expressions:
if expression is not None:
attach_hints(expression)
return expressions
