pypaimon/api/table_read.py

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import pandas as pd
import pyarrow as pa

from abc import ABC, abstractmethod
from pypaimon.api import Split
from typing import List, Optional, TYPE_CHECKING, Iterator

if TYPE_CHECKING:
    import ray
    from duckdb.duckdb import DuckDBPyConnection


class TableRead(ABC):
    """To read data from data splits."""

    @abstractmethod
    def to_iterator(self, splits: List[Split]) -> Iterator[tuple]:
        """Read data from splits and converted to pyarrow.Table format."""

    @abstractmethod
    def to_arrow(self, splits: List[Split]) -> pa.Table:
        """Read data from splits and converted to pyarrow.Table format."""

    @abstractmethod
    def to_arrow_batch_reader(self, splits: List[Split]) -> pa.RecordBatchReader:
        """Read data from splits and converted to pyarrow.RecordBatchReader format."""

    @abstractmethod
    def to_pandas(self, splits: List[Split]) -> pd.DataFrame:
        """Read data from splits and converted to pandas.DataFrame format."""

    @abstractmethod
    def to_duckdb(
            self,
            splits: List[Split],
            table_name: str,
            connection: Optional["DuckDBPyConnection"] = None) -> "DuckDBPyConnection":
        """Convert splits into an in-memory DuckDB table which can be queried."""

    @abstractmethod
    def to_ray(self, splits: List[Split]) -> "ray.data.dataset.Dataset":
        """Convert splits into a Ray dataset format."""