Question: How to insert data into a mySQL table when the data is stored in a variable?

I have lots of data that will be stored in variables and wish for it to be inserted into the database table.

Answer: 
This is no official notation. Besides the fact that prefixing things which are obvious through their signature is pointless, it will just confuse readers which are not familiar with that kind of notation.
As remarked by Anna Vopureta and Thomas Kilian, the notation used by your teacher is not standard UML. But as pointed out in the article of Martin Fowler recommended by Anna Vopureta, and missing in the asnwer of Thomas Kilian, it makes sense to distinguish between those operations/methods with return value that represent pure queries (not changing the state) and those that do not (due to state changes). 

So, we have to deal with three cases:

1. operations/methods without return value
2. operations/methods with return value
	1. changing the state
	2. not changing the state (pure queries)

A pure query method can be expressed in a UML class diagram by appending the operation property `query` in curly braces to the operation declaration.

In your example the correct operation declarations would be

```
+foo()
+bar1(): int
+bar2(): int {query}

```