Introduction to SQL

Selecting and sorting data


Ordering and commenting

Aggregating and calculating values

Joins and aliases

Figure 1

Join Diagram for Example

Figure 2

This figure shows the relations between the tables and helps to visualise joining or linking the tables in the database: Articles Database We will cover relational database design in the next episode. In addition to visual above, SQL Join Types Explained Visually provides visual/animated examples to help convey to learners what is happening in SQL JOINs.

Saving queries

Database design

Figure 1

OpenRefine DOAJ Sample Article Data

Figure 2

Fields, Records, Values

Figure 3

Articles Database

Figure 4

Introducing inconsistencies and normalising data

Creating tables and modifying data

Other database tools

Extra challenges (optional)

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