Class 1 | Week 9 | DAT601

Continuing from last lesson Todd is continuing with the introduction to SQL language.

Following along with MSDN material describing multiple concepts from Distinct & Order by, Joins, etc. Distinct removes repetitions within your query result.

Preliminary examples are displaying how not to execute select statement it would appear, considering his on board example is missing some key words he is conveying that the table will just be a mess of cross pollinated data. Instead we want a table which is simple to read.

Joins are an important part of SQL query language, these help us join related tables to each other in a multitude of styles that become integral to withdrawing data that is related to each other out of the database.

Todd described a multitude of join types and how they work. The important part of this is the results you want to draw out of the datbase, it's important to visualize columns of data you want, from there you can join by the tables you require and then add constraints via the where clause then order in your desired sequence.

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