paimon-python/pypaimon/table/object/object_read_builder.py

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#     http://www.apache.org/licenses/LICENSE-2.0
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from typing import List, Optional


class ObjectReadBuilder:
    """Read builder for ObjectTable.

    Supports projection (column selection) and limit (row count).
    """

    def __init__(self, table):
        from pypaimon.table.object.object_table import ObjectTable
        self.table: ObjectTable = table
        self._projection: Optional[List[str]] = None
        self._limit: Optional[int] = None

    def with_projection(self, projection: List[str]) -> "ObjectReadBuilder":
        self._projection = projection
        return self

    def with_limit(self, limit: int) -> "ObjectReadBuilder":
        self._limit = limit
        return self

    def new_scan(self):
        from pypaimon.table.object.object_table_scan import ObjectTableScan
        return ObjectTableScan(self.table)

    def new_read(self):
        from pypaimon.table.object.object_table_read import ObjectTableRead
        return ObjectTableRead(
            table=self.table,
            projection=self._projection,
            limit=self._limit,
        )