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325c6bdf3d
Reasons: - The cache will at some point store intermediate results as opposed to only query results. We should change the terminology now without having to worry about backward compat. - Equivalent caches in MySQL (1) and Starrocks (2) are called "query cache". - The new name is ca. 13.8% more catchy. (1) https://dev.mysql.com/doc/refman/5.6/en/query-cache.html (2) https://docs.starrocks.io/en-us/2.5/using_starrocks/query_cache
24 lines
998 B
SQL
24 lines
998 B
SQL
-- Tags: no-parallel
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-- Tag no-parallel: Messes with internal cache
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SET allow_experimental_query_cache = true;
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SYSTEM DROP QUERY CACHE;
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-- Run a silly query with a non-trivial plan and put the result into the query cache QC
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SELECT 1 + number from system.numbers LIMIT 1 SETTINGS use_query_cache = true;
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SELECT count(*) FROM system.query_cache;
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-- EXPLAIN PLAN should show the same regardless if the result is calculated or read from the QC
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EXPLAIN PLAN SELECT 1 + number from system.numbers LIMIT 1;
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EXPLAIN PLAN SELECT 1 + number from system.numbers LIMIT 1 SETTINGS use_query_cache = true; -- (*)
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-- EXPLAIN PIPELINE should show the same regardless if the result is calculated or read from the QC
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EXPLAIN PIPELINE SELECT 1 + number from system.numbers LIMIT 1;
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EXPLAIN PIPELINE SELECT 1 + number from system.numbers LIMIT 1 SETTINGS use_query_cache = true; -- (*)
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-- Statements (*) must not cache their results into the QC
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SELECT count(*) FROM system.query_cache;
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SYSTEM DROP QUERY CACHE;
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