package main

import (
    "database/sql"
    "fmt"
    "context"
    "log"
   _ "github.com/flarco/bigquery"
)


type Participant struct {
	Name string
	Splits []float64
}


func main() {

	db, err := sql.Open("bigquery", "bigquery://myProjectID/mydatasetID")
	if err != nil {
		log.Fatal(err)
	}
	defer db.Close()

	SQL := `WITH races AS (
		  SELECT "800M" AS race,
		    [STRUCT("Ben" as name, [23.4, 26.3] as splits), 
		 	 STRUCT("Frank" as name, [23.4, 26.3] as splits)
			]
		       AS participants)
		SELECT
		  race,
		  participant
		FROM races r
		CROSS JOIN UNNEST(r.participants) as participant`

	rows, err := db.QueryContext(context.Background(), SQL)
	if err != nil {
		log.Fatal(err)
	}
	defer rows.Close()
	for rows.Next() {
		if err := rows.Err(); err != nil {
			log.Fatal(err)
		}
		var race string
		var participant Participant
		err = rows.Scan(&race, &participant)
		fmt.Printf("fetched: %v %+v\n", race, participant)
		if err != nil {
			log.Fatal(err)
		}
	}
}

goos: darwin
goarch: amd64
pkg: github.com/flarco/bigquery/bench
cpu: Intel(R) Core(TM) i9-9980HK CPU @ 2.40GHz
Benchmark_Primitive_GCPClient
database/gcp: primitive types 3.918388531s
Benchmark_Primitive_GCPClient-16    	       1	3918442974 ns/op	42145144 B/op	  830647 allocs/op
Benchmark_Primitive_SQLDriver
database/sql: primitive types 2.880091637s
Benchmark_Primitive_SQLDriver-16    	       1	2880149491 ns/op	22301848 B/op	  334547 allocs/op
Benchmark_Complex_GCPClient
database/gcp: structured types 3.303497894s
Benchmark_Complex_GCPClient-16      	       1	3303548761 ns/op	11551216 B/op	  154660 allocs/op
Benchmark_Complex_SQLDriver
database/sql: structured types 2.690012577s
Benchmark_Complex_SQLDriver-16      	       1	2690056675 ns/op	 6643176 B/op	   71562 allocs/op
PASS