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Combining tables with an Equijoin

Combining tables with an Equijoin - SQL Tutorial

From the course: SQL for Non-Programmers

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Combining tables with an Equijoin

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One of the most powerful features of SQL is being able to join multiple tables together. Relational database design through normalization implies that we avoid using one large data table or the repetition of data in multiple tables. Instead, we break down data into smaller logical pieces stored in separate tables. Tables can then be connected through common keys, unique data values that are used in multiple tables, and act as a bridge. For example, imagine that you have two tables, one table with information about students and another table with their grades. If you want to know which are your top performing students and which ones are failing, you would need to connect these tables using a join. The common key would be a student ID that is found in both tables, allowing you to bridge a connection and combine the results of the table to retrieve relevant information. Let's move over to SLS and try this out on our Two Trees Olive Oil data. Within our olive oil database, we have been…

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