Working with JSON and nested data#

DuckDB’s demo parses JSON payloads directly into relational columns. DuckPlus exposes the same read_json helper while keeping the typed expression API available for schema validation and column derivations.

from pathlib import Path

from duckplus import DuckCon
from duckplus import io as duckio
from duckplus.typed import ducktype

manager = DuckCon()
with manager:
    events = duckio.read_json(
        manager,
        Path("data/events.json"),
        format="auto",  # aligns with DuckDB's default demo behaviour
        records=True,
        columns={
            "n": "INTEGER",
            "metrics": "STRUCT(likes INTEGER, shares INTEGER)",
        },
    )
    metrics = events.add(
        total_engagement=(
            ducktype.Numeric("metrics.likes")
            + ducktype.Numeric("metrics.shares")
        )
    )
    print(metrics.relation.fetchall())

DuckPlus forwards advanced options such as records, lines, maximum_depth, and ignore_errors exactly as DuckDB documents them. Use the typed DSL to project nested elements without losing column dependency tracking.

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