Course tips and study guides
Study plans, exam and interview preparation, projects and placements, from people a year or two ahead and the UniCircle team. Every tip names its author and is checked by an editor before it appears.
Topics#javascript#html#java#sql#react#accessibility#dsa#interview#nodejs#arrays#error handling#forms#oop#placements#postgresql#abstract classes#acid#aggregates
35 tips
- GuideEngineeringUndergraduatePromises and async/await without the confusionWhat a promise is, how async and await make asynchronous code read top to bottom, how to handle errors, and how to run independent tasks in parallel.#javascript#promises#async await#error handlingUniCircle team2 min
- GuideEngineeringUndergraduateJavaScript array methods you will use every daymap, filter, reduce, find, some, every and sort explained with one small data set, plus the sort mistake that catches almost everyone.#javascript#arrays#map filter reduce#sortUniCircle team2 min
- TipEngineeringUndergraduate== versus === and truthy values in JavaScriptWhy loose equality surprises people, the short list of falsy values, and safe ways to check for missing values with ?? and ?.#javascript#equality#truthy#nullishUniCircle team1 min
- GuideEngineeringUndergraduateJavaScript closures in 10 minutesWhat a closure is, why a function remembers the variables around it, and three places closures show up in real code and in interviews.#javascript#closures#functions#interviewUniCircle team2 min
- GuideEngineeringUndergraduatevar, let and const in JavaScript, and what hoisting really meansThe three ways to declare a variable, how their scope differs, what the temporal dead zone is, and a simple rule for which one to use.#javascript#let#const#hoistingUniCircle team2 min
- TipEngineeringFirst yearLinks, images and data attributes: small details that matterWriting link text people can understand, alt text that actually helps, safe links that open new tabs, and how data-* attributes connect HTML to your JavaScript.#html#links#alt text#data attributesUniCircle team2 min
- TipEngineeringFirst yearHTML tables done right: caption, headers and scopeWhen to use a table, how to mark up header cells so the data makes sense to everyone, and why tables should never be used for page layout.#html#tables#accessibilityUniCircle team1 min
- GuideEngineeringFirst yearHTML forms that work for everyoneLabels, the right input types, built-in validation and grouping: the small details that make a form usable on a phone and with a screen reader.#html#forms#accessibility#validationUniCircle team2 min
- GuideEngineeringFirst yearSemantic HTML: header, nav, main, article and why they matterHow to use HTML's meaning-carrying elements instead of a page full of divs, and what that gives you for accessibility, SEO and viva questions.#html#semantic html#accessibility#seoUniCircle team2 min
- GuideEngineeringFirst yearThe HTML page skeleton every student should knowThe handful of lines that belong at the top of every web page, what each one does, and the mistakes that make pages look broken on phones.#html#doctype#meta viewport#web basicsUniCircle team2 min
- GuideEngineeringUndergraduateWindow functions for interviews: ROW_NUMBER, RANK and running totalsThe three window-function patterns that solve most 'top N per group' and 'running total' questions in SQL interviews, with the difference between RANK and DENSE_RANK.#sql#window functions#rank#interviewUniCircle team2 min
- GuideEngineeringUndergraduateTransactions and constraints: keeping your data correctWhat BEGIN, COMMIT and ROLLBACK guarantee, what ACID means in plain words, and how PRIMARY KEY, FOREIGN KEY, UNIQUE and CHECK stop bad data at the door.#transactions#acid#constraints#foreign keyUniCircle team2 min
- GuideEngineeringUndergraduateHow to read EXPLAIN output and when an index helpsA student-friendly way to read a PostgreSQL query plan, spot a full table scan, and decide whether an index will actually make a query faster.#postgresql#explain#indexes#query performanceUniCircle team2 min
- GuideEngineeringUndergraduateSQL joins explained with two small tablesInner, left, right, full and self joins shown on the same two tiny tables, so you can see exactly which rows each one keeps.#sql#joins#left join#self joinUniCircle team2 min
- GuideEngineeringUndergraduateGROUP BY and HAVING without the confusionWhat GROUP BY actually does to your rows, why WHERE and HAVING are different, and the one rule about which columns you may select.#sql#group by#having#aggregatesUniCircle team2 min
- GuideEngineeringUndergraduateSQL filters and sorting: WHERE, IN, BETWEEN, LIKE and NULLHow to pick exactly the rows you want in SQL, including the NULL trap that catches most students, and how ORDER BY and LIMIT work together.#sql#where#null#order byUniCircle team2 min
- GuideEngineeringUndergraduatePostgreSQL commands you will use in your first weekThe psql shortcuts and SQL statements that cover almost everything a student does in a first DBMS lab: connect, look around, create a table, add rows, change them and clean up.#postgresql#sql#psql#dbms labUniCircle team2 min
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