Categorygithub.com/flarco/bigquery
modulepackage
0.0.9
Repository: https://github.com/flarco/bigquery.git
Documentation: pkg.go.dev

# README

BigQuery SQL Driver

BigQuery database/sql driver in Go. GoDoc

This library is compatible with Go 1.17+

Please refer to CHANGELOG.md if you encounter breaking changes.

This library provides fast implementation of the BigQuery Client as a database/sql drvier.

DSN Data Source Name

The BigQuery driver accepts the following DSN

  • 'bigquery://projectID/[location/]datasetID?queryString'

    Where queryString can optionally configure the following option:

    • credentialsFile
    • credentialJSON (with url-base64 encoded json)
    • endpoint
    • userAgent
    • apiKey
    • quotaProject
    • scopes

Since this library uses Google Cloud API you can pass your credentials via GOOGLE_APPLICATION_CREDENTIALS environment variable.

Usage:

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)
		}
	}
}

Benchmark

Benchmark runs 3 times the following queries:

  • primitive types:
   SELECT state,gender,year,name,number 
   FROM `bigquery-public-data.usa_names.usa_1910_2013` LIMIT 10000
  • complex type (repeated string/repeated record)
   SELECT  t.publication_number, t.inventor, t.assignee, t.description_localized 
   FROM `patents-public-data.patents.publications_202105` t ORDER BY 1 LIMIT 1000

In both case database/sql driver is faster and allocate way less memory than GCP BigQuery API Client

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

License

The source code is made available under the terms of the Apache License, Version 2, as stated in the file LICENSE.

Individual files may be made available under their own specific license, all compatible with Apache License, Version 2. Please see individual files for details.

Credits and Acknowledgements

Library Author: Adrian Witas

# Packages

No description provided by the author

# Functions

ExampleRowsNext fetching rows example.
NewConfig creates a new Config and sets default values.
NewConnector returns new driver.Connector.
ParseDSN parses the DSN string to a Config.

# Structs

Config is a configuration parsed from a DSN string.
Driver is exported to make the driver directly accessible.
Rows abstraction implements database/sql driver.Rows interface.
Statement abstraction implements database/sql driver.Statement interface.

# Type aliases

NamedValues represents name values slice.
Values represents value slice.