ConvertYesNo converts YES/NO to bool.

FormatErrorWithQuery will format the error with failed query.

GetSSHClient returns a ssh client.

IsDDL returns true if the given sql string is a DDL statement.

IsSelect returns true if the given sql string is a SELECT statement.

ProxyConnection proxies the connection between ssh client and listener.

SanitizeSQL removes comments, splits the sql by `;` and returns the trimmed sql statement array.

TrimStatement trims the unused characters from the statement for making getStatementWithResultLimit() happy.

PortFIFO is the fifo for SSH client port queue.