Immer is a tiny library that makes it possible to work with immutable data in JavaScript in a much more straight-forward way by operating on a temporarily draft state and using all the normal JavaScript API's and data structures. The first part of th…

Immutable.js offers the fromJS() method to build immutable structures from objects and array. Objects are converted into maps. Arrays are converted into lists. The fromJS() method can also take a reviver function for custom conversions.  Object to Im…

To demonstrate the difference between mutability and immutability, imagine taking a drink from a glass of water. If our glass is mutable, when we take a drink, we retain the same glass and change the amount of water in that glass. However, if our gla…

17.1.1.6 Creating a Data Snapshot Using Raw Data Files 创建一个数据快照使用 Raw Data Files 如果数据库是大的, 复制raw 数据文件可以变的更加有效相比使用mysqldump 和导入文件在每个slave上. 这个即使跳过更新索引的负载 使用这种方法 表在存储引擎具有复杂的caching和logging 算法需要额外的步骤来产生一个完全的时间点快照. 初始的copy命令需要留下cache信息和记录更新,即使你需要的一个全局的读锁…

17.1.1.5 Creating a Data Snapshot Using mysqldump 创建一个快照使用mysqldump: 创建一个数据快照的方式是使用mysqldump 工具来备份所有你需要的的数据库. 一旦 数据dump已经完成,你然后可以导入数据到slave 在启动复制进程前 例子 显示dumps 所有的数据到一个文件叫做dbdump.db, 包含 --master-data 选项 会自动增加CHANGE MASTER TO 语句 slave需要用于启动复制进程: shell…

原文: http://halistechnology.com/2015/05/28/use-javascript-to-export-your-data-as-csv/ ----------------------------------------------------- Use JavaScript to Export Your Data as CSV 28 MAY 2015 on Javascript, csv, export, data 101155 Do you know what…

w https://openproceedings.org/2014/conf/icdt/FigueiraFA14.pdf From a database perspective, however, Core-XPath fails to include the single most important construct in a query language: the join. Without the ability to relate nodes based on the actual…

Immutable.js provides several conversion methods to migrate one structure to another. Each Immutable.js class contains a prefixed "to" method like Map.toList(), Map.toSet(), etc. Converting these types sometimes results in a loss of data, as we…

Learn how to query an Immutable.Map() using get, getIn, has, includes, find, first and last. These are powerful operators that make finding data in an object graph pain free. has, includes, contains: //has() var map = Immutable.Map({a: '10'}); consol…

<%@LANGUAGE="JAVASCRIPT" CODEPAGE="65001"%> <% //塗聚文 //20131021 function getData(connectionString, sql){ var result = null; var adStateOpen = 1; var connection = new ActiveXObject("ADODB.CONNECTION"); try{ connection…