[sqlite] BLOBs and sqlite_exec

[Will Leshner]

Sorry if this is terribly obvious, but I'm assuming that, in SQLite3, 
we can't use the sqlite_exec convenience API to store BLOBs, right? I 
see that if we go through the VM directly the API allows us to specify 
a data size, so that it doesn't depend on NULL-terminated C strings. 
But sqlite_exec does no such thing, right?