Andile Khosa
@andilekhosa2
IS Student ๐จ๐ฟโ๐ป Manchester United๐ด Tsonga ๐ค
ID: 1416999704202731524
19-07-2021 05:54:17
194 Tweet
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๐๐จ๐ฎ๐ญ๐ก ๐๐๐ซ๐ข๐๐ ๐ฟ๐ฆ, ๐ข๐ญโ๐ฌ ๐ฒ๐จ๐ฎ๐ซ ๐ญ๐ข๐ฆ๐ ๐ญ๐จ ๐๐จ๐๐ ๐ญ๐ก๐ ๐๐ฎ๐ญ๐ฎ๐ซ๐. The Huawei Developer Competition โ Code4Mzansi is officially here. As Huaweiโs flagship global developer event, this competition has attracted 800,000+ developers across 50+ countries since
๐๐๐๐ ๐๐ฌ๐ฌ๐๐ญ ๐๐๐ง๐๐ ๐๐ฆ๐๐ง๐ญ ๐๐ข๐ฆ๐ข๐ญ๐๐ is Hiring โผ๏ธ ๐ฉโ๐ปData Analyst Intern ๐ Remote | 3 months | Paid โช๏ธ Strong interest in Data Analytics and business insights โช๏ธ Good command of Microsoft Excel (advanced formulas, Power Query, Power Pivot, VBA, data mining,
๐ซ NEVER Use COUNT to Check for Existence If you just want to confirm if a particular item exists in your data, do not use COUNT() with a filter (WHERE clause). SELECT COUNT(*) FROM users WHERE email = '[email protected]'; The problem is that COUNT(*) answers a different
SQL Mistakes Beginners Should Avoid ๐: 1๏ธโฃ Using SELECT * โข Pulls unused columns โข Slows queries โข Breaks when schema changes โข Use only required columns 2๏ธโฃ Ignoring NULL Values โข NULL breaks calculations โข COUNT(column) skips NULL โข Use COALESCE or IS NULL checks 3๏ธโฃ