rangebar-patterns

ClickHouse SQL anti-patterns and performance constraints discovered during Gen200-Gen600 barrier framework. Use when writing ClickHouse SQL, creating new barrier/pattern generations, modifying array functions, window functions, parameter sweeps, forward arrays, or encountering slow queries, OOM, NULL entry prices, wrong barrier detection, arrayFirstIndex returning 0, or aligning SQL results with backtesting.py. TRIGGERS - ClickHouse SQL, barrier SQL, array function, window function, trailing stop SQL, parameter sweep, slow query, OOM, arrayFirstIndex, leadInFrame, groupArray, arrayFold, arrayScan, threshold-relative, anti-pattern, performance constraint, forward arrays, self-join, O(N×M), SQL vs Python, SQL vs backtesting.

Brute-force pattern sweep methodology for range bar microstructure discovery. Guidelines (not constraints) for designing, executing, and evaluating new sweep generations. Use when creating Gen600+, designing feature sweeps, setting barrier parameters, choosing evaluation metrics, or reviewing sweep results. TRIGGERS - new generation, Gen600, sweep design, feature sweep, barrier grid, evaluation metrics, cross-asset validation, multiple testing, Kelly fraction, Bonferroni, signal count, rolling window, quantile method.