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Database Indexing Trade-offs
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Database Indexing Trade-offs

HardSQL · PostgreSQL

Problem

Can you describe the trade-offs between different database indexing strategies?

Use the supplied PostgreSQL benchmark data to compare each strategy quantitatively. Include strategies without qualifying benchmark runs so the result reflects both measured performance and missing evidence.

Output

  1. One row per index strategy, ordered by overall cost score ascending, with unscored strategies last.
  2. Columns: strategy_name, index_method, index_size_mb, benchmark_count, avg_read_latency_ms, avg_write_latency_ms, and tradeoff_score.
  3. Round latency and score values to two decimal places. Use NULL for unavailable averages or scores.

Schema

index_strategies
ColumnTypeDescription
strategy_idPKINTUnique identifier for an indexing strategy
strategy_nameVARCHAR(100)Name of the index strategy
index_methodVARCHAR(30)PostgreSQL index access method
index_size_mbDECIMAL(10,2)Estimated storage consumed by the index
write_overhead_pctDECIMAL(5,2)Estimated percentage of write overhead
notesVARCHAR(255)Optional strategy notes
benchmark_runs
ColumnTypeDescription
run_idPKINTUnique benchmark run identifier
strategy_idINTReferenced indexing strategy
workloadVARCHAR(30)Workload category used by the benchmark
read_latency_msDECIMAL(10,2)Measured read latency in milliseconds
write_latency_msDECIMAL(10,2)Measured write latency in milliseconds
rows_examinedINTNumber of rows examined during the run
Tablesindex_strategiesbenchmark_runs
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