Articles by tag: query-optimization

SELECT queries in ClickHouse: differences from PostgreSQL, PREWHERE, SAMPLE

PREWHERE, SAMPLE, FINAL, IN vs JOIN, FORMAT, top 10 queries for betting analytics. How to migrate SQL from PostgreSQL to ClickHouse without errors.

MergeTree in ClickHouse: granules, parts, and sparse index

MergeTree structure using a bids table example: part, granule, mark, merge of parts, ORDER BY vs PRIMARY KEY, partitioning, EXPLAIN indexes, partition management.

Uniform DB Sharding: Data Distribution and Search Strategies

Explore uniform sharding methods for horizontal scaling of databases. Learn about ID generation, paging, and query optimization in distributed systems.