Columnar Storage
Columnar storage keeps each column’s values together so a query reads only the columns it names — at the price of expensive row lookups and small writes.
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Predicate Pushdown
Understand when a reader can apply filters or skip data, why overlapping statistics are only candidates, and how to verify actual work.
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Row Group and Column Chunk
Distinguish Parquet row groups, column chunks, and pages, and see how row group size affects writer memory, statistics-based skipping, and parallel reads.
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Apache Arrow
Distinguish Arrow memory buffers from storage encoding, understand IPC exchange, and check the conditions needed for zero-copy access.
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Avro
Learn how Avro uses writer and reader schemas, why nullable fields still need read defaults, and how container files differ from event framing.
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ORC
Understand ORC stripes, column streams, and indexes, and check reader support before assuming a filter skips storage work.
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Parquet
Understand Parquet row groups, column chunks, and optional statistics, and separate a file format from table transactions.