Query

Abstract query-result class. A query result provides an iterator that returns a map for each record of a query result.

The map should be keyed by the column names, and the values should use the following types:

• boolean returned as integer 1 or 0 (to ensure consistency with MySQL that doesn't have native booleans)
• integer types returned as integers
• floating point / decimal types returned as floats
• strings returned as strings
• dates / datetimes returned as strings

Note that until SilverStripe 4.3, bugs meant that strings were used for every column type.

Once again, this should be subclassed by an actual database implementation. It will only ever be constructed by a subclass of SS_Database. The result of a database query - an iteratable object that's returned by DB::SS_Query

Primarily, the Query class takes care of the iterator plumbing, letting the subclasses focusing on providing the specific data-access methods that are required: {@link nextRecord()}, {@link numRecords()} and {@link seek()}