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  • Factorial Growth of Subqueries When Using Nested WITH Clauses in ClickHouse

    calendar Jan 12, 2024 · 5 min read · Databases  ·
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    ClickHouse is a popular OLAP database. It speaks SQL and earns the reputation of "fast and resource efficient". But the support of SQL comes with surprises if not careful. In this blog, I show that a simple query of nested WITH clauses in ClickHouse generates factorial number of subqueries. The simple query …


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Peng Zhang

Software Engineer

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