Method walkProjectionFunc

datasource/sqlite/sqlrewrite.go:357–365

Take an expression func, ensure we don't do runtime-checking (as the function) doesn't really exist, then map that function to an Mongo Aggregation/MapReduce function min, max, avg, sum, cardinality, terms Single Value Aggregates: min, max, avg, sum, cardinality, count MultiValue aggregates: term

(node *expr.FuncNode)

//      terms, ??
//
func (m *rewrite) walkProjectionFunc(node *expr.FuncNode) (expr.Node, error) {
	switch funcName := strings.ToLower(node.Name); funcName {
	case "count":
		return node, nil
	default:
		u.Warnf("not implemented %v", funcName)
	}
	return node, nil
}

func eval(cur expr.Node) (value.Value, bool) {
	switch curNode := cur.(type) {