fixtures/dictionary_reencoded/scenario.json

{
  "schema_version": "1.0",
  "scenario_id": "dictionary_reencoded",
  "title": "Dictionary contents change without any value change",
  "category": "representation",
  "description": "Both versions store the same dictionary<int8, string> column with the same decoded values. The stored dictionaries differ: v0 has a different order and an entry that no row uses; v1 has exactly the used values. Schema, rows and values are unchanged, so both versions have the same logical fingerprint.",
  "notes": [
    "Tools that compare dictionary indices, category lists or category codes observe a change here. The decoded values do not change.",
    "The unused dictionary entry survives a PyArrow round trip; other readers may rebuild the dictionary on read and drop it."
  ],
  "tags": [
    "dictionary",
    "categorical",
    "encoding",
    "no-schema-change",
    "no-value-change"
  ],
  "row_identity": [
    "id"
  ],
  "versions": [
    {
      "id": "v0",
      "file": "v0.parquet",
      "row_count": 6,
      "fingerprint": "sha256:6dfdbf0a9de0eac2a01b3d7a88cb06abe18009dfa4d033259c14f39d7bf16d9b",
      "schema": [
        {
          "name": "id",
          "type": "int64",
          "nullable": false
        },
        {
          "name": "status",
          "type": "dictionary<values=string, indices=int8, ordered=0>",
          "nullable": true
        }
      ],
      "writer": {
        "use_dictionary": true
      },
      "dictionaries": [
        {
          "path": "status",
          "values": [
            "pending",
            "active",
            "inactive",
            "archived"
          ]
        }
      ]
    },
    {
      "id": "v1",
      "file": "v1.parquet",
      "row_count": 6,
      "fingerprint": "sha256:6dfdbf0a9de0eac2a01b3d7a88cb06abe18009dfa4d033259c14f39d7bf16d9b",
      "schema": [
        {
          "name": "id",
          "type": "int64",
          "nullable": false
        },
        {
          "name": "status",
          "type": "dictionary<values=string, indices=int8, ordered=0>",
          "nullable": true
        }
      ],
      "writer": {
        "use_dictionary": true
      },
      "dictionaries": [
        {
          "path": "status",
          "values": [
            "active",
            "inactive",
            "pending"
          ]
        }
      ]
    }
  ],
  "transitions": [
    {
      "from": "v0",
      "to": "v1",
      "mutations": [],
      "invariants": {
        "row_count_preserved": true,
        "row_identity_preserved": true,
        "rows_retained": true,
        "paths_retained": true,
        "common_values_preserved": true,
        "value_changes": [],
        "parquet_schema_preserved": true
      }
    }
  ]
}