MySQL: What does the equal colon =: mean in an update statement?

mysql, variables

Solution

That is likely referencing a bind variable. The PHP or other code that executes the MySQL statement replaces the reference with a variable.

Problem

I came across the following MySQL query: ``` update 'table' set itemId=:itemId, startDate=:startDate where id=:id ``` However I could not figure out what the =: means. I think that the name after the =: is a variable but then how to check what's inside or how is it set?

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