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columnar storage
Store a column together so a scan of one field does not read the whole row. Wrong tool for “fetch this order.”
What is columnar storage?
Columnar formats (Parquet and column stores) lay each column contiguously and compress similar values. Aggregations read only the columns they need. Point lookups of a full row are what row stores are for.
Why does columnar storage matter when vibe coding?
Models put the app on a warehouse, or export the warehouse as a heap of JSON. Name the access pattern first.
How do you do columnar storage?
OLTP stays row-oriented. Analytical scans use columnar files with partition and column pruning. Do not serve a checkout from Parquet.
How do you ask a model for columnar storage?
Store (analytical table) as columnar (Parquet or a column store), partitioned by (date). Do not use it for point lookups of single orders. Do not put OLTP on it.
What goes wrong with columnar storage?
Tiny row-groups or one file per row. You bought columnar layout and then defeated the scan.