{
    "role": "dimension",
    "time": {
        "range": null,
        "column": null,
        "has_gaps": null,
        "granularity": "unknown"
    },
    "grain": [
        "service_point_id"
    ],
    "table": "data-ge.water_meter_info",
    "columns": [
        {
            "name": "supply_office",
            "dtype": "string",
            "stats": {
                "max": null,
                "min": null,
                "std": null,
                "mean": null,
                "skewness": null
            },
            "comment": "非空；11 个枚举值（GE 约束）",
            "enumish": true,
            "null_rate": 0.0,
            "top_values": [],
            "semantic_type": "dimension",
            "distinct_count": 11,
            "distinct_ratio": 0.03666666666666667,
            "pk_candidate_score": 0.05,
            "metric_candidate_score": 0.0
        },
        {
            "name": "station",
            "dtype": "string",
            "stats": {
                "max": null,
                "min": null,
                "std": null,
                "mean": null,
                "skewness": null
            },
            "comment": "非空；36 个枚举值（GE 约束）",
            "enumish": true,
            "null_rate": 0.0,
            "top_values": [],
            "semantic_type": "dimension",
            "distinct_count": 36,
            "distinct_ratio": 0.12,
            "pk_candidate_score": 0.1,
            "metric_candidate_score": 0.0
        },
        {
            "name": "district",
            "dtype": "string",
            "stats": {
                "max": null,
                "min": null,
                "std": null,
                "mean": null,
                "skewness": null
            },
            "comment": "非空；13 个枚举值（GE 约束）",
            "enumish": true,
            "null_rate": 0.0,
            "top_values": [],
            "semantic_type": "dimension",
            "distinct_count": 13,
            "distinct_ratio": 0.043333333333333335,
            "pk_candidate_score": 0.05,
            "metric_candidate_score": 0.0
        },
        {
            "name": "meter_diameter",
            "dtype": "string",
            "stats": {
                "max": null,
                "min": null,
                "std": null,
                "mean": null,
                "skewness": null
            },
            "comment": "非空；8 个枚举值（GE 约束）",
            "enumish": true,
            "null_rate": 0.0,
            "top_values": [],
            "semantic_type": "dimension",
            "distinct_count": 8,
            "distinct_ratio": 0.02666666666666667,
            "pk_candidate_score": 0.03,
            "metric_candidate_score": 0.0
        },
        {
            "name": "meter_status",
            "dtype": "string",
            "stats": {
                "max": null,
                "min": null,
                "std": null,
                "mean": null,
                "skewness": null
            },
            "comment": "非空；单一取值（\"有效\"）",
            "enumish": true,
            "null_rate": 0.0,
            "top_values": [],
            "semantic_type": "dimension",
            "distinct_count": 1,
            "distinct_ratio": 0.0033333333333333335,
            "pk_candidate_score": 0.0,
            "metric_candidate_score": 0.0
        },
        {
            "name": "meter_subtype",
            "dtype": "string",
            "stats": {
                "max": null,
                "min": null,
                "std": null,
                "mean": null,
                "skewness": null
            },
            "comment": "非空；9 个枚举值（GE 约束）",
            "enumish": true,
            "null_rate": 0.0,
            "top_values": [],
            "semantic_type": "dimension",
            "distinct_count": 9,
            "distinct_ratio": 0.03,
            "pk_candidate_score": 0.03,
            "metric_candidate_score": 0.0
        },
        {
            "name": "meter_type",
            "dtype": "string",
            "stats": {
                "max": null,
                "min": null,
                "std": null,
                "mean": null,
                "skewness": null
            },
            "comment": "非空；5 个枚举值（GE 约束）",
            "enumish": true,
            "null_rate": 0.0,
            "top_values": [],
            "semantic_type": "dimension",
            "distinct_count": 5,
            "distinct_ratio": 0.016666666666666666,
            "pk_candidate_score": 0.02,
            "metric_candidate_score": 0.0
        },
        {
            "name": "installation_position",
            "dtype": "string",
            "stats": {
                "max": null,
                "min": null,
                "std": null,
                "mean": null,
                "skewness": null
            },
            "comment": "非空；4 个枚举值（GE 约束）",
            "enumish": true,
            "null_rate": 0.0,
            "top_values": [],
            "semantic_type": "dimension",
            "distinct_count": 4,
            "distinct_ratio": 0.013333333333333334,
            "pk_candidate_score": 0.02,
            "metric_candidate_score": 0.0
        },
        {
            "name": "service_point_id",
            "dtype": "unknown",
            "stats": {
                "max": null,
                "min": null,
                "std": null,
                "mean": null,
                "skewness": null
            },
            "comment": "命名指示标识列；未提供唯一性或非空验证",
            "enumish": null,
            "null_rate": null,
            "top_values": [],
            "semantic_type": "id",
            "distinct_count": null,
            "distinct_ratio": null,
            "pk_candidate_score": 0.6,
            "metric_candidate_score": 0.05
        },
        {
            "name": "account_id",
            "dtype": "unknown",
            "stats": {
                "max": null,
                "min": null,
                "std": null,
                "mean": null,
                "skewness": null
            },
            "comment": "命名指示账户标识；未提供唯一性或非空验证",
            "enumish": null,
            "null_rate": null,
            "top_values": [],
            "semantic_type": "id",
            "distinct_count": null,
            "distinct_ratio": null,
            "pk_candidate_score": 0.5,
            "metric_candidate_score": 0.05
        }
    ],
    "quality": {
        "warning_hints": [
            "以下列未设置非空校验：service_point_id, account_id（空值情况未知）",
            "未识别到时间列"
        ],
        "failed_expectations": []
    },
    "row_count": 300,
    "fk_candidates": [],
    "confidence_notes": [
        "role 判定为 dimension：表内列均为枚举/分类或ID，未发现数值型度量或时间列；34/34 期望均为分类枚举/非空与去重比例。",
        "grain 猜测为 service_point_id：仅依据命名启发式，缺少唯一性与非空度量佐证（置信度较低）。",
        "未识别时间列：列名与期望均未涉及日期/时间，也无最小/最大时间范围可推断。"
    ],
    "primary_key_candidates": []
}