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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
33 lines
909 B
SQL
33 lines
909 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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-- Start with empty query cache QC and query log
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SYSTEM DROP QUERY CACHE;
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DROP TABLE system.query_log SYNC;
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-- Run a query with QC on. The first execution is a QC miss.
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SELECT '---';
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SELECT 1 SETTINGS use_query_cache = true;
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SYSTEM FLUSH LOGS;
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SELECT ProfileEvents['QueryCacheHits'], ProfileEvents['QueryCacheMisses']
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FROM system.query_log
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WHERE type = 'QueryFinish'
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AND query = 'SELECT 1 SETTINGS use_query_cache = true;';
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-- Run previous query again with query cache on
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SELECT '---';
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SELECT 1 SETTINGS use_query_cache = true;
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DROP TABLE system.query_log SYNC;
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SYSTEM FLUSH LOGS;
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SELECT ProfileEvents['QueryCacheHits'], ProfileEvents['QueryCacheMisses']
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FROM system.query_log
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WHERE type = 'QueryFinish'
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AND query = 'SELECT 1 SETTINGS use_query_cache = true;';
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SYSTEM DROP QUERY CACHE;
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