{
  "table": "ecommerce_orders",
  "row_count": 10000,
  "role": "fact",
  "grain": ["order_id"],
  "time": {
    "column": "order_date",
    "granularity": "day",
    "range": ["2024-04-20", "2025-04-19"],
    "has_gaps": false
  },
  "columns": [
    {
      "name": "order_id",
      "dtype": "string",
      "semantic_type": "id",
      "null_rate": 0.0,
      "distinct_count": 10000,
      "distinct_ratio": 1.0,
      "stats": {"min": null, "max": null, "mean": null, "std": null, "skewness": null},
      "enumish": false,
      "top_values": [],
      "pk_candidate_score": 1.0,
      "metric_candidate_score": 0.0,
      "comment": ""
    },
    {
      "name": "customer_id",
      "dtype": "integer",
      "semantic_type": "dimension",
      "null_rate": 0.0,
      "distinct_count": 2713,
      "distinct_ratio": 0.2713,
      "stats": {"min": 1, "max": 2999, "mean": 995.29, "std": null, "skewness": null},
      "enumish": false,
      "top_values": [],
      "pk_candidate_score": 0.3,
      "metric_candidate_score": 0.1,
      "comment": ""
    },
    {
      "name": "product_id",
      "dtype": "integer",
      "semantic_type": "dimension",
      "null_rate": 0.0,
      "distinct_count": 1000,
      "distinct_ratio": 0.0999,
      "stats": {"min": 1, "max": 1000, "mean": 504.87, "std": null, "skewness": null},
      "enumish": true,
      "top_values": [],
      "pk_candidate_score": 0.1,
      "metric_candidate_score": 0.1,
      "comment": ""
    },
    {
      "name": "category",
      "dtype": "string",
      "semantic_type": "dimension",
      "null_rate": 0.0,
      "distinct_count": 6,
      "distinct_ratio": 0.0006,
      "stats": {"min": null, "max": null, "mean": null, "std": null, "skewness": null},
      "enumish": true,
      "top_values": [
        {"value": "Beauty", "pct": null},
        {"value": "Books", "pct": null},
        {"value": "Clothing", "pct": null},
        {"value": "Electronics", "pct": null},
        {"value": "Home", "pct": null},
        {"value": "Toys", "pct": null}
      ],
      "pk_candidate_score": 0.0,
      "metric_candidate_score": 0.0,
      "comment": ""
    },
    {
      "name": "price",
      "dtype": "float",
      "semantic_type": "metric",
      "null_rate": 0.0,
      "distinct_count": 9013,
      "distinct_ratio": 0.9013,
      "stats": {"min": 5.06, "max": 499.93, "mean": 252.55, "std": null, "skewness": null},
      "enumish": false,
      "top_values": [],
      "pk_candidate_score": 0.0,
      "metric_candidate_score": 0.9,
      "comment": ""
    },
    {
      "name": "quantity",
      "dtype": "integer",
      "semantic_type": "metric",
      "null_rate": 0.0,
      "distinct_count": 9,
      "distinct_ratio": 0.0009,
      "stats": {"min": 1, "max": 9, "mean": 2.12, "std": null, "skewness": null},
      "enumish": true,
      "top_values": [
        {"value": 1, "pct": null},
        {"value": 2, "pct": null},
        {"value": 3, "pct": null},
        {"value": 4, "pct": null},
        {"value": 5, "pct": null}
      ],
      "pk_candidate_score": 0.0,
      "metric_candidate_score": 0.7,
      "comment": ""
    },
    {
      "name": "order_date",
      "dtype": "string",
      "semantic_type": "time",
      "null_rate": 0.0,
      "distinct_count": 365,
      "distinct_ratio": 0.0365,
      "stats": {"min": "2024-04-20", "max": "2025-04-19", "mean": null, "std": null, "skewness": null},
      "enumish": false,
      "top_values": [],
      "pk_candidate_score": 0.0,
      "metric_candidate_score": 0.0,
      "comment": ""
    },
    {
      "name": "shipping_date",
      "dtype": "string",
      "semantic_type": "time",
      "null_rate": 0.0,
      "distinct_count": 371,
      "distinct_ratio": 0.0371,
      "stats": {"min": "2024-04-21", "max": "2025-04-26", "mean": null, "std": null, "skewness": null},
      "enumish": false,
      "top_values": [],
      "pk_candidate_score": 0.0,
      "metric_candidate_score": 0.0,
      "comment": ""
    },
    {
      "name": "delivery_status",
      "dtype": "string",
      "semantic_type": "dimension",
      "null_rate": 0.0,
      "distinct_count": 4,
      "distinct_ratio": 0.0004,
      "stats": {"min": null, "max": null, "mean": null, "std": null, "skewness": null},
      "enumish": true,
      "top_values": [
        {"value": "Delivered", "pct": null},
        {"value": "Pending", "pct": null},
        {"value": "Returned", "pct": null},
        {"value": "Shipped", "pct": null}
      ],
      "pk_candidate_score": 0.0,
      "metric_candidate_score": 0.0,
      "comment": ""
    },
    {
      "name": "payment_method",
      "dtype": "string",
      "semantic_type": "dimension",
      "null_rate": 0.0,
      "distinct_count": 5,
      "distinct_ratio": 0.0005,
      "stats": {"min": null, "max": null, "mean": null, "std": null, "skewness": null},
      "enumish": true,
      "top_values": [
        {"value": "Apple Pay", "pct": null},
        {"value": "Credit Card", "pct": null},
        {"value": "Debit Card", "pct": null},
        {"value": "Google Pay", "pct": null},
        {"value": "PayPal", "pct": null}
      ],
      "pk_candidate_score": 0.0,
      "metric_candidate_score": 0.0,
      "comment": ""
    },
    {
      "name": "device_type",
      "dtype": "string",
      "semantic_type": "dimension",
      "null_rate": 0.0,
      "distinct_count": 3,
      "distinct_ratio": 0.0003,
      "stats": {"min": null, "max": null, "mean": null, "std": null, "skewness": null},
      "enumish": true,
      "top_values": [
        {"value": "Desktop", "pct": null},
        {"value": "Mobile", "pct": null},
        {"value": "Tablet", "pct": null}
      ],
      "pk_candidate_score": 0.0,
      "metric_candidate_score": 0.0,
      "comment": ""
    },
    {
      "name": "channel",
      "dtype": "string",
      "semantic_type": "dimension",
      "null_rate": 0.0,
      "distinct_count": 4,
      "distinct_ratio": 0.0004,
      "stats": {"min": null, "max": null, "mean": null, "std": null, "skewness": null},
      "enumish": true,
      "top_values": [
        {"value": "Email", "pct": null},
        {"value": "Organic", "pct": null},
        {"value": "Paid Search", "pct": null},
        {"value": "Social", "pct": null}
      ],
      "pk_candidate_score": 0.0,
      "metric_candidate_score": 0.0,
      "comment": ""
    },
    {
      "name": "shipping_address",
      "dtype": "string",
      "semantic_type": "text",
      "null_rate": 0.0,
      "distinct_count": 10000,
      "distinct_ratio": 1.0,
      "stats": {"min": null, "max": null, "mean": null, "std": null, "skewness": null},
      "enumish": false,
      "top_values": [],
      "pk_candidate_score": 0.9,
      "metric_candidate_score": 0.0,
      "comment": ""
    },
    {
      "name": "billing_address",
      "dtype": "string",
      "semantic_type": "text",
      "null_rate": 0.0,
      "distinct_count": 10000,
      "distinct_ratio": 1.0,
      "stats": {"min": null, "max": null, "mean": null, "std": null, "skewness": null},
      "enumish": false,
      "top_values": [],
      "pk_candidate_score": 0.9,
      "metric_candidate_score": 0.0,
      "comment": ""
    },
    {
      "name": "customer_segment",
      "dtype": "string",
      "semantic_type": "dimension",
      "null_rate": 0.0,
      "distinct_count": 3,
      "distinct_ratio": 0.0003,
      "stats": {"min": null, "max": null, "mean": null, "std": null, "skewness": null},
      "enumish": true,
      "top_values": [
        {"value": "New", "pct": null},
        {"value": "Returning", "pct": null},
        {"value": "VIP", "pct": null}
      ],
      "pk_candidate_score": 0.0,
      "metric_candidate_score": 0.0,
      "comment": ""
    }
  ],
  "primary_key_candidates": [["order_id"]],
  "fk_candidates": [
    {"from": "customer_id", "to": "dim_customer(customer_id)", "confidence": 0.9},
    {"from": "product_id", "to": "dim_product(product_id)", "confidence": 0.9}
  ],
  "quality": {
    "failed_expectations": [],
    "warning_hints": []
  },
  "confidence_notes": [
    "表含时间列(order_date, shipping_date)且含度量列(price, quantity)，推断为fact表。",
    "order_id唯一性=1.0，确认主键。",
    "order_date日期范围连续无缺口，粒度为日级。",
    "高基数数值字段(price, quantity)符合指标特征。",
    "低熵字段(category, delivery_status, payment_method等)为枚举维度。"
  ]
}