Open a dedicated driver client / pool for a URL or config. The caller owns it: pass it to readSql as
many times as needed (readSql never closes a client it was given) and call close() when done. This is the
supported way to share one connection across reads; with MS SQL Server it is also the only way to hold two
databases open at once (each client has its own ConnectionPool, nothing touches the driver's global pool).
Open a dedicated driver client / pool for a URL or config. The caller owns it: pass it to
readSqlas many times as needed (readSql never closes a client it was given) and callclose()when done. This is the supported way to share one connection across reads; with MS SQL Server it is also the only way to hold two databases open at once (each client has its ownConnectionPool, nothing touches the driver's global pool).