ClickHouse Performance Tuning。MergeTree Family (Replicated/Distributed/Aggregating)・PARTITION BY・ORDER BY (Primary Key)・Sample By・SETTINGS index_granularity=8192・Projection (Materialized View代替)・Aggregating Materialized View・MaterializedPostgreSQL ENGINE・Dictionary External Source・SAMPLE 0.1・FINAL Modifier・Vertical Merge Algorithm・MergeTree Compression LZ4/ZSTD・¥0 OSS、2026年ClickHouse 25.1 Vector Search内蔵対応。