Use globally-defined ADODB_FETCH_MODE if it is false on the object in getAssoc

[letynsoft]

In my Ubuntu 22.10, I've come to an issue with the getAssoc function.
It was a version 5.21.4, but i believe the current implementation did not fix the underlying issue.

I think that in case the connection fetchMode is false, the global $ADODB_FETCH_MODE should be used instead.

[dregad]

@mnewnham do you remember the reason for using the Connection's fetch mode here, instead of the RecordSet's ?

I'm thinking that since we now have $adodbFetchMode defined in the Recordset, it would make sense to use that and not rely on the Connection, what do you think ?

See also #958, which cleans up initialization of RecordSet $fetchMode.

[dregad]

@mnewnham it would be great to have your feedback on this.

[mnewnham]

If I remember correctly:
We use the fetchMode in getAssoc() rather than ADODB_FETCH_MODE because we use this method chained from other internals. example

1. We start with a procedure that sets the $ADODB_FETCH_MODE to FETCH_ASSOC
2. We then call an internal function MetaColumns(). This requires that the fetch mode is FETCH_NUM
3. We save the current fetch mode in the MetaColumns method and switch $fetchMode to FETCH_NUM
4. We execute getAssoc with the fetchMode of FETCH_NUM even though ADODB_FETCH_MODE is FETCH_ASSOC
5. We return the results of getAssoc to MetaColumns, process it out, then switch the fetchMode back to FETCH_ASSOC

We have also talked about deprecating globals like ADODB_FETCH_MODE and bringing them into class variables because it prevents us controlling 2 simultaneous connections properly. For example if I open an Oracle connection in FETCH_NUM mode and a MySQL connection in FETCH_ASSOC mode, I have to reset the global before every call to the database.