When you send a query to MySQL, you usually don't need to think explicitly about the types of the expressions in your query. If you compare this to a lot of programming languages, you'll find that it's not always the way things work. In strongly typed languages like Java, for example, typing is very strict.
In this respect, MySQL is much more like a dynamically typed language such as PHP or Perl --- a DWIM (do what I mean) typing system. Yet, internally, every expression in MySQL has a type, and it does conversions amongst them as needed.
Sometimes, you might wonder how does this query work and exactly what's happening to the variables in these expressions? Importantly, does it always work right?
Examples of MySQL Type Conversion
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