What is the meaning of <> in mysql query?

Question

I have a MySQL query that includes <> in it. I don\'t know the exact usage of it.

SELECT * FROM table_laef WHERE id = ? AND genre_type <> \'LIVE\'
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Answer 1

In MySQL, I use <> to preferentially place specific rows at the front of a sort request.

For instance, under the column topic, I have the classifications of 'Chair', 'Metabolomics', 'Proteomics', and 'Endocrine'. I always want to list any individual(s) with the topic 'Chair', first, and then list the other members in alphabetical order based on their topic and then their name_last.

I do this with:

SELECT scicom_list ORDER BY topic <> 'Chair',topic,name_last;

This outputs the rows in the order of:
Chair
Endocrine
Metabolomics
Proteomics

Notice that topic <> 'Chair' is used to select all the rows with 'Chair' first. It then sorts the rows where topic = Chair by name_last.*

*This is a bit counterintuitive since <> equals != based on other feedback in this post.

This syntax can also be used to prioritize multiple categories. For instance, if I want to have "Chair" and then "Vice Chair" listed before the rest of the topics, I use the following

SELECT scicom_list ORDER BY topic <> 'Chair',topic <> 'Vice Chair',topic,name_last;

This outputs the rows in the order of:
Chair
Vice Chair
Endocrine
Metabolomics
Proteomics