)]}'
{
  "commit": "71c418c2fde3c49d4cfa4ec564514d04f66f71bf",
  "tree": "bc29ebc89b823daf25ef8bb6f79b441059beaf64",
  "parents": [
    "db9fff8638e907012b4fb4585723ebbc6514ab20"
  ],
  "author": {
    "name": "Joana Hrotko",
    "email": "joana.hrotko@dremio.com",
    "time": "Mon Jan 19 13:41:06 2026 +0000"
  },
  "committer": {
    "name": "GitHub",
    "email": "noreply@github.com",
    "time": "Mon Jan 19 14:41:06 2026 +0100"
  },
  "message": "GH-948: Use buffer indexing for UUID vector (#949)\n\n## What\u0027s Changed\n\nThe current UUID vector implementation creates new buffer slices when\nreading values through holders, which has several drawbacks:\n- Memory overhead: Each slice creates a new ArrowBuf object\n- Performance impact: Buffer slicing is slower than direct buffer\nindexing\n- Inconsistency: Other fixed-width types (like Decimal) use buffer\nindexing with a `start` offset field\n\n### Proposed Changes\n\n1. Add `start` field to UUID holders to track buffer offsets:\n   - `UuidHolder`: Add `public int start \u003d 0;`\n   - `NullableUuidHolder`: Add `public int start \u003d 0;`\n2. Update `UuidVector` to use buffer indexing\n3. Update readers and writers\n\n### Related Work\n\n- Original UUID extension type implementation: GH-825 (#903)\n\nCloses #948",
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