go_one

README

go_one

go_one finds N+1(strictly speaking call SQL in a for loop) query in go

Example

package main

import (
	"database/sql"
	"fmt"
	"log"
	_ "github.com/go-sql-driver/mysql"
)


type Person struct {
	Name string
	JobID int
}

type Job struct {
	JobID int
	Name string
}

func main(){

	cnn, _ := sql.Open("mysql", "user:password@tcp(host:port)/dbname")

	rows, _ := cnn.Query("SELECT name, job_id FROM persons")

	defer rows.Close()

	for rows.Next() {
		var person Person
		if err := rows.Scan(&person.Name,&person.JobID); err != nil {
			log.Fatal(err)
		}

		var job Job

        // This is N+1 query
		if err := cnn.QueryRow("SELECT job_id, name FROM Jobs WHERE job_id = ?",person.JobID).Scan(&job.JobID,&job.Name); err != nil { 
			log.Fatal(err)
		}
		fmt.Println(person.Name,job.Name)
	}

}

output

./hoge.go:38:13: this query is called in a loop

Install

go get github.com/masibw/go_one/cmd/go_one

Usage

bash

go vet -vettool=`which go_one` ./...

fish

go vet -vettool=(which go_one) ./...

Library Support

• sql
• sqlx
• gorp
• gorm

Contribute

You're welcome to build an Issue or create a PR and be proactive!

Caution

This tool does not support calls to functions from other packages in a for loop

Documentation

Index

• Variables

Variables

var Analyzer = &analysis.Analyzer{
	Name: "go_one",
	Doc:  doc,
	Run:  run,
	Requires: []*analysis.Analyzer{
		inspect.Analyzer,
	},
}

Analyzer is ...