READS

READS精品文章

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  聊聊JDBC事务隔离级别（修正）

  ...的事务隔离级别到底会如何影响事务的并发，脏读(dirty reads), 不可重复读(non-repeatable reads)，幻读(phantom reads)到底是什么概念 事务 原子性(atomicity) 事务是数据库的逻辑工作单位，而且是必须是原子工作单位，对于其数据修改，...

  suxier 2019-07-31 16:20 评论0 收藏0
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  聊聊JDBC事务隔离级别（修正）

  ...的事务隔离级别到底会如何影响事务的并发，脏读(dirty reads), 不可重复读(non-repeatable reads)，幻读(phantom reads)到底是什么概念 事务 原子性(atomicity) 事务是数据库的逻辑工作单位，而且是必须是原子工作单位，对于其数据修改，...

  phpmatt 2019-08-14 14:35 评论0 收藏0
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  Linuxc - posix信号量的应用（生产者-消费者）

  ...r writing! ); } } else { printf(customer reads %d bytes from the FIFO , real_read); } sem_post(&avail); sem_post(&mutex); } pthread...

  marek 2019-08-08 11:55 评论0 收藏0
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  聚集索引：SQL Server 进阶 Level 3

  ...1 row(s) affected) Table SalesOrderDetail_noindex. Scan count 1, logical reads 1495. Clustered Index (1 row(s) affected) Table SalesOrderDetail_noindex. Scan count 1, logical reads 3. Impact of...

  SimpleTriangle 2019-07-01 15:49 评论0 收藏0
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  深入非聚集索引：SQL Server索引进阶 Level 2

  ...引 (2130 row(s) affected) Table Contacts_noindex. Scan count 1, logical reads 568. 有索引 (2130 row(s) affected) Table Contacts_index. Scan count 1, logical reads 14. 索引冲突 IO reduced from 568 reads...

  array_huang 2019-07-01 15:49 评论0 收藏0
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  MySql优化之key_buffer_size的设置

  ...mory (Needed 16777220 bytes) 通过检查状态值Key_read_requests和Key_reads，可以知道key_buffer_size设置是否合理。比例key_reads /key_read_requests应该尽可能的低，至少是1:100，1:1000更好（上述状态值可以使用SHOW STATUS LIKE ‘key_read%获得）。Key_reads/...

  leanxi 2019-07-31 18:34 评论0 收藏0
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  智能数据库之智能调参

  ...ake an example. I already have history data with two metrics (innodb_pages_reads, innodb_io_reads), three workloads (TPCC, YCSB, wikipedia) and four configrations. So I can get two matrices: Matrix...

  saucxs 2019-06-26 16:26 评论0 收藏0
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  [Leetcode] Read N Characters Given Read4 用Read4 AP

  Read N Characters Given Read4 I The API: int read4(char *buf) reads 4 characters at a time from a file. The return value is the actual number of characters read. For example, it returns 3 if there is...

  wayneli 2019-08-14 12:36 评论0 收藏0
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  mysql实现nextVal功能

  ...函数过程中出现This function has none of DETERMINISTIC, NO SQL, or READS SQL DATA in its de 错误 这是我们开启了bin-log, 我们就必须指定我们的函数是否是1 DETERMINISTIC 不确定的2 NO SQL 没有SQl语句，当然也不会修改数据3 READS SQL DATA 只是读取数据，...

  sixgo 2019-08-19 10:52 评论0 收藏0
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  [LeetCode] 9. Palindrome Number

  ...ine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward as forward. Example 1: Input: 121Output: trueExample 2: Input: -121Output: falseExplanation: From ...

  zhaochunqi 2019-08-16 13:43 评论0 收藏0
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  包含列的索引：SQL Server索引进阶 Level 5

  ...n 1: No Nonclustered Index Table SalesOrderDetail. Scan count 1, logical reads 1238. Non read activity: 8%. Run 2: Index – No Included Columns Table SalesOrderDetail. Scan count 1, logical read...

  boredream 2019-07-01 15:49 评论0 收藏0
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  lxc和virtualbox和物理机的简单性能测试和对比

  ...sbench。 CPU采用如下指令测试。 sysbench --test=cpu --num-threads=2 --cpu-max-prime=50000 run 文件IO采用如下指令测试。 sysbench --test=fileio --file-total-size=10G prepare sysbench --test=fileio --file-tota...

  mindwind 2019-05-23 19:46 评论0 收藏0
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  使用sysbench对mysql压力测试

  ...ode=select --oltp-read-only=on --oltp-skip-trx=on --max-time=120 --num-threads=12 [prepare|run|cleanup] 注意最后一行，一项测试开始前需要用prepare来准备好表和数据，run执行真正的压测，cleanup用来清除数据和表。实际prepare的表结构： mysql> desc dbt...

  Null 2019-07-31 16:08 评论0 收藏0
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  利用html2canvas实现移动端上传图片生成海报

  ...at = this imageInput.addEventListener(change, function (e) { reads = new FileReader() reads.readAsDataURL(this.files[0]) reads.addEventListener(load, function (e) { ...

  Cruise_Chan 2019-08-26 13:49 评论0 收藏0
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  [LeetCode] 158. Read N Characters Given Read4 II -

  Problem The API: int read4(char *buf) reads 4 characters at a time from a file. The return value is the actual number of characters read. For example, it returns 3 if there is only 3 characters left i...

  周国辉 2019-08-16 13:48 评论0 收藏0