While I was playing with mysqlslap for my local benchmarks I got an error that puzzled me :

You have an error in your SQL syntax; ...

After analysing the query and running it with the CLI mysql client and in other tools I tried to write the query on one line.

That was the solution, it seems mysqlslap only accepts one line queries :/

I tried with the following version

mysqlslap  Ver 1.0 Distrib 5.1.39, for pc-linux-gnu (i686)

‘Hope that helps