mysql - 随笔分类(第11页) - papering

myisamchk

摘要：myisamchk 阅读全文

posted @ 2017-01-12 23:24 papering 阅读(120) 评论(0) 推荐(0)

摘要：http://dev.mysql.com/doc/refman/5.7/en/string-functions.html#function_substring-index 阅读全文

posted @ 2017-01-10 14:33 papering 阅读(184) 评论(0) 推荐(0)

摘要：1 ALTER TABLE ad_keyword_brand 2 ADD CONSTRAINT w1 UNIQUE (keyword,adasin,brand,page_position,country,ad_kind,ad_tag); 阅读全文

posted @ 2017-01-09 17:00 papering 阅读(189) 评论(0) 推荐(0)

buffer pool

摘要：https://dev.mysql.com/doc/refman/5.5/en/glossary.html#glos_buffer_pool buffer pool The memory area that holds cached InnoDB data for both tables and i 阅读全文

posted @ 2016-12-30 16:03 papering 阅读(171) 评论(0) 推荐(0)

http://highscalability.com/blog/2015/5/18/how-mysql-is-able-to-scale-to-200-million-qps-mysql-cluster.html

摘要：http://highscalability.com/blog/2015/5/18/how-mysql-is-able-to-scale-to-200-million-qps-mysql-cluster.html 阅读全文

posted @ 2016-12-30 15:40 papering 阅读(140) 评论(0) 推荐(0)

faster with MyISAM tables than with InnoDB or NDB tables

摘要：http://dev.mysql.com/doc/refman/5.7/en/partitioning-limitations.html Performance considerations. Some effects of partitioning operations on performanc 阅读全文

posted @ 2016-12-30 15:19 papering 阅读(189) 评论(0) 推荐(0)

MEMORY Storage Engine MEMORY Tables TEMPORARY TABLE max_heap_table_size

摘要：http://dev.mysql.com/doc/refman/5.7/en/create-table.html You can use the TEMPORARY keyword when creating a table. A TEMPORARY table is visible only to 阅读全文

posted @ 2016-12-30 14:46 papering 阅读(283) 评论(0) 推荐(0)

situations where MyISAM will be faster than InnoDB

摘要：http://www.tocker.ca/categories/myisam Converting MyISAM to InnoDB and a lesson on variance I'm about to start working through converting a large MySQ 阅读全文

posted @ 2016-12-30 11:52 papering 阅读(171) 评论(0) 推荐(0)

1920.154s 0.309s 30817

摘要：MyISAM HASH restart-buffer 阅读全文

posted @ 2016-12-30 10:21 papering 阅读(209) 评论(0) 推荐(0)

算法构成时间复杂度

摘要：总结： 1、一个算法由控制结构（顺序、分支和循环3种）和原操作（指固有数据类型的操作）构成的，则算法时间取决于两者的综合效果。 2、 N*N矩阵乘法算法时间复杂度T(n)=O(n^3) for(i=1;i<=n;i++) for(j=1;j<=n;j++) c[i][j]=0 for(k=1;k 阅读全文

posted @ 2016-12-29 19:54 papering 阅读(388) 评论(0) 推荐(0)

only for equality comparisons Hash Index Characteristics

摘要：http://dev.mysql.com/doc/refman/5.7/en/index-btree-hash.html Hash Index Characteristics Hash indexes have somewhat different characteristics from thos 阅读全文

posted @ 2016-12-29 19:16 papering 阅读(181) 评论(0) 推荐(0)

NULL-safe equal null 索引空字符串

摘要：小结 1、 mysql> INSERT INTO my_table (phone) VALUES (NULL); 有手机号但是不知道 mysql> INSERT INTO my_table (phone) VALUES ('');没有手机号 http://dev.mysql.com/doc/refm 阅读全文

posted @ 2016-12-29 19:06 papering 阅读(472) 评论(0) 推荐(0)

Why MySQL could be slow with large tables ?

摘要：https://www.percona.com/blog/2006/06/09/why-mysql-could-be-slow-with-large-tables/ 阅读全文

posted @ 2016-12-29 18:56 papering 阅读(161) 评论(0) 推荐(0)

The index also can be used for LIKE comparisons if the argument to LIKE is a constant string that does not start with a wildcard character.

摘要：http://dev.mysql.com/doc/refman/5.7/en/index-btree-hash.html MySQL 5.7 Reference Manual / ... / Comparison of B-Tree and Hash Indexes 9.3.8 Comparison 阅读全文

posted @ 2016-12-29 17:02 papering 阅读(148) 评论(0) 推荐(0)

a single statement, not multiple statements

摘要：http://dev.mysql.com/doc/refman/5.7/en/prepare.html Statement names are not case sensitive. preparable_stmt is either a string literal or a user varia 阅读全文

posted @ 2016-12-29 10:59 papering 阅读(146) 评论(0) 推荐(0)

MySQL 5.6.3

摘要：SHOW VARIABLES LIKE '%version%'; https://dev.mysql.com/doc/refman/5.6/en/explain.html As of MySQL 5.6.3, permitted explainable statements for EXPLAIN 阅读全文

posted @ 2016-12-28 20:02 papering 阅读(225) 评论(0) 推荐(0)

SELECT 'www' = 0; 1

摘要：http://dev.mysql.com/doc/refman/5.7/en/type-conversion.html MySQL 5.7 Reference Manual / Functions and Operators / Type Conversion in Expression Evalu 阅读全文

posted @ 2016-12-27 19:09 papering 阅读(221) 评论(0) 推荐(0)

SET ? DECLARE

摘要：http://dev.mysql.com/doc/refman/5.7/en/declare-local-variable.html http://dev.mysql.com/doc/refman/5.7/en/set-variable.html SET Syntax for Variable As 阅读全文

posted @ 2016-12-27 18:40 papering 阅读(179) 评论(0) 推荐(0)

Defining Stored Programs

摘要：ok ok http://dev.mysql.com/doc/refman/5.7/en/stored-programs-defining.html 阅读全文

posted @ 2016-12-27 18:11 papering 阅读(191) 评论(0) 推荐(0)

MYSQL PASSWORD()

摘要：https://www.pythian.com/blog/hashing-algorithm-in-mysql-password-2/ 阅读全文

posted @ 2016-12-27 12:04 papering 阅读(163) 评论(0) 推荐(0)

papering

随笔分类 - mysql