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Showing posts from August, 2015

Build React Native App (4) - Redux, Jest, and NativeBase

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From this blog, typescript feature will be added. There are couple of ways to implement static type checking like; flow from facebook, PropTypes and Typescript.Typescript is well integrated with Visual Studio Code and supports better linter, error messages, and intellisense.Reference siteGithub Sample Ex4Currnet versionD:\GitRepo\reactnative>npm --version 6.3.0 D:\GitRepo\reactnative>react-native --version react-native-cli: 2.0.1 react-native: n/a - not inside a React Native project directory D:\GitRepo\reactnative>yarn --version 1.9.4 Creating React Native App$ react-native init ex4 If you want to specify the version, add "--version 0.57.3" at the end.Add NativeBase to React Native$ npm install native-base --save ... + native-base@2.8.1 added 71 packages from 42 contributors, removed 50 packages, updated 829 packages and audited 34989 packages in 138.542s found 0 vulnerabilities $ $ yarn yarn install v1.9.4 warning package-lock.json found. Your project contains l…

SQL Performance Tip #1: Avoid Case or isnull function from where clause

IntroductionI have performance issue with our query and if a query is not designed carefully, the performance will see the big difference.The query having performance has two issues; 1. case statement from “where” clause to implement dynamic query and 2. null data handling.Original Queryselect * from tablename
where CASE WHEN @includeICL=1 THEN 1 ELSE isnull(gbkmut.debnr,0) END not in (100989,100990,100991,100992) When this query was run, it took 4 secs to complete this query no matter what the value of @includeICL.Removing case statementIf you try to search about dynamic query performance issue, you will see lots of recommendation. In general, my recommendation is “Don’t use case statement for conditional filter”. There are couple of good articles how to replace case statement with boolean operation. In this case, the case statement can be replace with following statement
Where
(@includeICL=1 or isnull(gbkmut.debnr,0) not in (100989,100990,100991,100992)) Good thing for this quer…