connection

type DB interface {
	// Clone returns a stateful copy of this connection.
	Clone() DB
	// QueryIter returns closure allowing to load/fetch roads one by one.
	QueryIter(ctx context.Context, statement string, fields []string, args ...interface{}) (ResultFetchIter, error)
	// EQueryIter is QueryIter but will use EscapeArgs.
	EQueryIter(ctx context.Context, statement string, fields []string, args ...interface{}) (ResultFetchIter, error)
	// Query returns a closure that allows fetching of the results of the query.
	Query(ctx context.Context, statement string, fields []string, args ...interface{}) (ResultFetch, error)
	// EQuery is Query but will use EscapeArgs.
	EQuery(ctx context.Context, statement string, fields []string, args ...interface{}) (ResultFetch, error)
	// QueryPrimitive returns a closure that allows fetching of the results of a query to a
	// slice of primitives.
	QueryPrimitive(ctx context.Context, statement string, field string, args ...interface{}) (ResultFetch, error)
	// EQueryPrimitive is QueryPrimitive but will use EscapeArgs
	EQueryPrimitive(ctx context.Context, statement string, field string, args ...interface{}) (ResultFetch, error)
	// Raw ins intended to be an all raw query that runs statement with args and tries
	// to retrieve the results into fields without much magic whatsoever.
	Raw(ctx context.Context, statement string, args []interface{}, fields ...interface{}) error
	// ERaw is Raw but will use EscapeArgs
	ERaw(ctx context.Context, statement string, args []interface{}, fields ...interface{}) error
	// Exec is intended for queries that do not yield results (data modifiers)
	Exec(ctx context.Context, statement string, args ...interface{}) error
	// ExecResult is intended for queries that modify data and respond with how many rows were affected.
	ExecResult(ctx context.Context, statement string, args ...interface{}) (int64, error)
	// EExec is Exec but will use EscapeArgs.
	EExec(ctx context.Context, statement string, args ...interface{}) error
	// BeginTransaction returns a new DB that will use the transaction instead of the basic conn.
	BeginTransaction(ctx context.Context) (DB, error)
	// CommitTransaction commits the transaction
	CommitTransaction(ctx context.Context) error
	// RollbackTransaction rolls back the transaction
	RollbackTransaction(ctx context.Context) error
	// IsTransaction indicates if the DB is in the middle of a transaction.
	IsTransaction() bool
	// Set allows to change settings for the current transaction.
	Set(ctx context.Context, set string) error
	// BulkInsert Inserts in the most efficient way possible a lot of data.
	BulkInsert(ctx context.Context, tableName string, columns []string, values [][]interface{}) (execError error)
}

type DatabaseHandler interface {
	// Open must be able to connect to the handled engine and return a db.
	Open(context.Context, *Information) (DB, error)
}

type Information struct {
	Database        string
	User            string
	Password        string
	ConnMaxLifetime *time.Duration

	CustomDial func(ctx context.Context, network, addr string) (net.Conn, error)

	// MaxConnPoolConns where applies will be used to determine the maximum amount of connections
	// a pool can have.
	MaxConnPoolConns int

	Logger   logging.Logger
	LogLevel LogLevel
}

type LogLevel string

type ResultFetch func(interface{}) error

type ResultFetchIter func(interface{}) (bool, func(), error)