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Databasesbeginner

SQL from Zero

Query, combine and summarise data with SQL, the language behind almost every app and analytics team.

Lessons
15 lessons in 4 modules
Study time
about 8 hours
Duration
~4 weeks at your own pace

Free plan: counts as one of your 2 new courses this month. Plans

What you'll learn

  • Write SELECT queries with filters, sorting and aggregates
  • Combine tables with joins and subqueries
  • Design simple tables with keys and constraints
  • Answer real business questions from a sample database

Syllabus

  1. Module 1Querying one tableSELECT, WHERE and ORDER BY.4 lessons
    1. Databases, tables and rowsExplain how relational databases store data.20 min
    2. SELECT and WHERERetrieve and filter rows from a table.30 min
    3. Sorting, limits and text matchingSort results and search text with LIKE.30 min
    4. NULL values and conditional logicHandle missing values and use CASE expressions.30 min
  2. Module 2Summarising dataAggregates and grouping.3 lessons
    1. COUNT, SUM, AVG, MIN and MAXSummarise a table with aggregate functions.30 min
    2. GROUP BY and HAVINGCalculate totals per group and filter groups.30 min
    3. Dates and timesGroup and filter by day, month and year.30 min
  3. Module 3Combining tablesJoins and subqueries.4 lessons
    1. Inner joinsCombine related rows from two tables.30 min
    2. Left joins and finding missing dataKeep unmatched rows and find customers with no orders.30 min
    3. Subqueries and CTEsBreak a complex question into steps with WITH.30 min
    4. Window functionsRank rows and compute running totals.30 min
  4. Module 4Designing and changing dataTables, keys and safe updates.4 lessons
    1. Creating tables, keys and constraintsDesign tables with primary and foreign keys.30 min
    2. INSERT, UPDATE and DELETE safelyChange data without accidentally changing everything.30 min
    3. Indexes and query speedExplain how indexes make queries faster.30 min
    4. Project: answer 10 business questionsUse everything so far to analyse the shop database.45 min