iterator.go

// Copyright (c) 2012-present The upper.io/db authors. All rights reserved.
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package db

// Iterator provides methods for iterating over query results.
type Iterator interface {
	// ResultMapper provides methods to retrieve and map results.
	ResultMapper

	// Scan dumps the current result into the given pointer variable pointers.
	Scan(dest ...interface{}) error

	// NextScan advances the iterator and performs Scan.
	NextScan(dest ...interface{}) error

	// ScanOne advances the iterator, performs Scan and closes the iterator.
	ScanOne(dest ...interface{}) error

	// Next dumps the current element into the given destination, which could be
	// a pointer to either a map or a struct.
	Next(dest ...interface{}) bool

	// Err returns the last error produced by the cursor.
	Err() error

	// Close closes the iterator and frees up the cursor.
	Close() error
}