05 2024 档案
摘要:第一部分 Optimizing the MySQL Server This section discusses optimization techniques for the database server, primarily dealing with system configuration r
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摘要:第一部分 Buffering and Caching MySQL uses several strategies that cache information in memory buffers to increase performance. 1 InnoDB Buffer Pool Optimi
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摘要:3.7 Statement Execution Time Optimizer Hints The MAX_EXECUTION_TIME hint is permitted only for SELECT statements. It places a limit N (a timeout value
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摘要:3.2 Optimizer Hint Syntax Optimizer hints must be specified within /*+ ... */ comments. That is, optimizer hints use a variant of /* ... */ C-style co
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摘要:MySQL provides optimizer control through system variables that affect how query plans are evaluated, switchable optimizations, optimizer and index hin
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摘要:书接上回 • Recursive (JSON property: recursive) This indicates that the row applies to the recursive SELECT part of a recursive common table expression. •
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摘要:Depending on the details of your tables, columns, indexes, and the conditions in your WHERE clause, the MySQL optimizer considers many techniques to e
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摘要:InnoDB is the storage engine that MySQL customers typically use in production databases where reliability【rɪˌlaɪə'bɪləti 可靠性;】 and concurrency【并发;】 ar
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摘要:In your role as a database designer, look for the most efficient way to organize your schemas, tables, and columns. As when tuning application code, y
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摘要:1.以才自足,以能自矜【jīn;自骄自傲。】,则为小人所忌,亦为君子所薄。 凭借才能自满,有能力而自夸,会被小人所嫉,也被君子看轻。 2.大处着眼,小处着手;群居守口,独居守心。 看事情要高瞻远瞩,有全局意识,考虑长远,做事的时候要谨慎,着手细节,才能避免眼高手低的毛病。和一群人相处的时候要谨言慎行
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摘要:9 Comparison of B-Tree and Hash Indexes Understanding the B-tree and hash data structures can help predict【prɪˈdɪkt 预测;预报;预言;预告;】 how different querie
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摘要:The best way to improve the performance of SELECT operations is to create indexes on one or more of the columns that are tested in the query. The inde
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摘要:1.Optimizing INFORMATION_SCHEMA Queries Applications that monitor databases may make frequent【ˈfriːkwənt , friˈkwent 频繁的;经常发生的;】 use of INFORMATION_SC
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摘要:4 Optimizing Derived Tables, View References, and Common Table Expressions with Merging or Materialization The optimizer can handle derived table refe
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摘要:The MySQL query optimizer has different strategies available to evaluate【ɪˈvæljueɪt 评价;评估;估计;】 subqueries: • For a subquery used with an IN, = ANY, or
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摘要:18 DISTINCT Optimization DISTINCT combined with ORDER BY needs a temporary table in many cases. Because DISTINCT may use GROUP BY, learn how MySQL wor
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摘要:15 IS NULL Optimization MySQL can perform the same optimization on col_name IS NULL that it can use for col_name = constant_value. For example, MySQL
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摘要:11 Multi-Range Read Optimization Reading rows using a range scan on a secondary index can result in many random disk accesses to the base table when t
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摘要:8.Nested Join Optimization The syntax for expressing joins permits nested joins. The syntax of table_factor is extended in comparison with the SQL Sta
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摘要:3.Index Merge Optimization The Index Merge access method retrieves rows with multiple range scans and merges【ˈmɜːrdʒɪz (使)合并,结合,并入;融入;相融;渐渐消失在某物中;】 th
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摘要:Queries, in the form of SELECT statements, perform all the lookup operations in the database. Tuning these statements is a top priority, whether to ac
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摘要:Optimization involves【ɪnˈvɑːlvz 需要;影响;(使)参加,加入;包含;牵涉;牵连;使成为必然部分(或结果);】 configuring, tuning, and measuring performance, at several levels. Depending on
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摘要:1.Delayed Replication MySQL supports delayed replication such that a replica server deliberately【dɪˈlɪbərətli 故意;蓄意;存心;从容不迫地;不慌不忙地;小心翼翼地;】 executes tr
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摘要:In addition to the built-in asynchronous replication, MySQL 8.0 supports an interface to semisynchronous replication that is implemented【ˈɪmplɪmentɪd
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摘要:1. Replication for purposes --Using Replication for Backups Replication can be used in many different environments for a range of purposes. To use rep
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摘要:1.Seconds_Behind_Source The SHOW REPLICA STATUS statement, which you must execute on each replica, provides information about the configuration and st
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摘要:Rocky Linux 官方宣布,Rocky Linux 9.0 操作系统全面上市,可作为 CentOS Linux 和 CentOS Stream 的直接替代品。有些安装需要测试验证的。 1.下载的安装包 2.安装的过程 此安装包, Rocky Linux 环境下安装,与在centos7.9 下安
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