sub_select produces invalid SQL sometimes

[parsonsmatt]

This PR currently adds a failing test to demonstrate the problem. Issue was initially filed in #79.

[bitemyapp]

SqlError {sqlState = "42883", sqlExecStatus = FatalError, sqlErrorMsg = "function array_remove(record) does not exist", sqlErrorDetail = "", sqlErrorHint = "No function matches the given name and argument types. You might need to add explicit type casts."}