Query reader

Module to define behaviour to read from a query.

QueryReader

Bases: Reader

Class to read data from a query.

Source code in mkdocs/lakehouse_engine/packages/io/readers/query_reader.py

class QueryReader(Reader):
    """Class to read data from a query."""

    def __init__(self, input_spec: InputSpec) -> None:
        """Construct QueryReader instances.

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

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

        Returns:
            A dataframe containing the data from the query.
        """
        if not self._input_spec.query:
            raise ValueError("query must be provided for query reader.")
        return ExecEnv.SESSION.sql(self._input_spec.query)

__init__(input_spec)

Construct QueryReader instances.

Parameters:

Name	Type	Description	Default
input_spec	InputSpec	input specification.	required

Source code in mkdocs/lakehouse_engine/packages/io/readers/query_reader.py

def __init__(self, input_spec: InputSpec) -> None:
    """Construct QueryReader instances.

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

read()

Read data from a query.

Returns:

Type	Description
DataFrame	A dataframe containing the data from the query.

Source code in mkdocs/lakehouse_engine/packages/io/readers/query_reader.py

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

    Returns:
        A dataframe containing the data from the query.
    """
    if not self._input_spec.query:
        raise ValueError("query must be provided for query reader.")
    return ExecEnv.SESSION.sql(self._input_spec.query)