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Table reader

Module to define behaviour to read from tables.

TableReader

Bases: Reader

Class to read data from a table.

Source code in mkdocs/lakehouse_engine/packages/io/readers/table_reader.py 
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class TableReader(Reader):
    """Class to read data from a table."""

    def __init__(self, input_spec: InputSpec):
        """Construct TableReader instances.

        Args:
            input_spec: input specification.
        """
        super().__init__(input_spec)

    def read(self) -> DataFrame:
        """Read data from a table.

        Returns:
            A dataframe containing the data from the table.
        """
        if self._input_spec.read_type == ReadType.BATCH.value:
            return ExecEnv.SESSION.read.options(
                **self._input_spec.options if self._input_spec.options else {}
            ).table(self._input_spec.db_table)
        elif self._input_spec.read_type == ReadType.STREAMING.value:
            return ExecEnv.SESSION.readStream.options(
                **self._input_spec.options if self._input_spec.options else {}
            ).table(self._input_spec.db_table)
        else:
            self._logger.error("The requested read type is not supported.")
            raise NotImplementedError

__init__(input_spec)

Construct TableReader instances.

Parameters:

Name Type Description Default
input_spec InputSpec

input specification.

 required
Source code in mkdocs/lakehouse_engine/packages/io/readers/table_reader.py 
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def __init__(self, input_spec: InputSpec):
    """Construct TableReader instances.

    Args:
        input_spec: input specification.
    """
    super().__init__(input_spec)

read()

Read data from a table.

Returns:

Type Description
DataFrame

A dataframe containing the data from the table.
Source code in mkdocs/lakehouse_engine/packages/io/readers/table_reader.py 
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def read(self) -> DataFrame:
    """Read data from a table.

    Returns:
        A dataframe containing the data from the table.
    """
    if self._input_spec.read_type == ReadType.BATCH.value:
        return ExecEnv.SESSION.read.options(
            **self._input_spec.options if self._input_spec.options else {}
        ).table(self._input_spec.db_table)
    elif self._input_spec.read_type == ReadType.STREAMING.value:
        return ExecEnv.SESSION.readStream.options(
            **self._input_spec.options if self._input_spec.options else {}
        ).table(self._input_spec.db_table)
    else:
        self._logger.error("The requested read type is not supported.")
        raise NotImplementedError