WIP: Replace prepare statements with plain queries

[caius]

We're forced to run through a transaction based connection pool, which doesn't support prepared statements due to connections being swapped out between the collector and the database server.

Replace all the explicit prepare/query calls with plain query calls instead.

Not expecting this to be accepted upstream, but its the version we're running internally that's working for us.

[lfittl]

We're forced to run through a transaction based connection pool, which doesn't support prepared statements due to connections being swapped out between the collector and the database server.

Replace all the explicit prepare/query calls with plain query calls instead.

Not expecting this to be accepted upstream, but its the version we're running internally that's working for us.

Thanks for sharing!

Clearly my assumptions in #793 were incorrect, since we explicitly call the functions that produce prepared statements.

We'll discuss internally how to go about this to address it one way or the other. For context, we do generally discourage running a connection pooler between the pganalyze collector and the database, but understand that in certain deployments this is hard to avoid.