superset/db_engine_specs/oracle.py

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# to you under the Apache License, Version 2.0 (the
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from datetime import datetime
from typing import Any, List, Optional, Tuple

from superset.db_engine_specs.base import BaseEngineSpec, LimitMethod
from superset.utils import core as utils


class OracleEngineSpec(BaseEngineSpec):
    engine = "oracle"
    engine_name = "Oracle"
    limit_method = LimitMethod.WRAP_SQL
    force_column_alias_quotes = True
    max_column_name_length = 30

    _time_grain_expressions = {
        None: "{col}",
        "PT1S": "CAST({col} as DATE)",
        "PT1M": "TRUNC(CAST({col} as DATE), 'MI')",
        "PT1H": "TRUNC(CAST({col} as DATE), 'HH')",
        "P1D": "TRUNC(CAST({col} as DATE), 'DDD')",
        "P1W": "TRUNC(CAST({col} as DATE), 'WW')",
        "P1M": "TRUNC(CAST({col} as DATE), 'MONTH')",
        "P0.25Y": "TRUNC(CAST({col} as DATE), 'Q')",
        "P1Y": "TRUNC(CAST({col} as DATE), 'YEAR')",
    }

    @classmethod
    def convert_dttm(cls, target_type: str, dttm: datetime) -> Optional[str]:
        tt = target_type.upper()
        if tt == utils.TemporalType.DATE:
            return f"TO_DATE('{dttm.date().isoformat()}', 'YYYY-MM-DD')"
        if tt == utils.TemporalType.DATETIME:
            datetime_formatted = dttm.isoformat(timespec="seconds")
            return f"""TO_DATE('{datetime_formatted}', 'YYYY-MM-DD"T"HH24:MI:SS')"""
        if tt == utils.TemporalType.TIMESTAMP:
            return f"""TO_TIMESTAMP('{dttm
                .isoformat(timespec="microseconds")}', 'YYYY-MM-DD"T"HH24:MI:SS.ff6')"""
        return None

    @classmethod
    def epoch_to_dttm(cls) -> str:
        return "TO_DATE('1970-01-01','YYYY-MM-DD')+(1/24/60/60)*{col}"

    @classmethod
    def epoch_ms_to_dttm(cls) -> str:
        return "TO_DATE('1970-01-01','YYYY-MM-DD')+(1/24/60/60/1000)*{col}"

    @classmethod
    def fetch_data(
        cls, cursor: Any, limit: Optional[int] = None
    ) -> List[Tuple[Any, ...]]:
        """
        :param cursor: Cursor instance
        :param limit: Maximum number of rows to be returned by the cursor
        :return: Result of query
        """
        if not cursor.description:
            return []
        return super().fetch_data(cursor, limit)