point get -1 on bigint unsigned primary key gets max.uInt64 value

[darren]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. What did you do?
   If possible, provide a recipe for reproducing the error.

package main

import (
	"database/sql"
	"fmt"
	"log"

	_ "github.com/go-sql-driver/mysql"
)

func main() {
	db, err := sql.Open("mysql", "root@tcp(127.0.0.1:4000)/test")
	if err != nil {
		log.Fatal(err)
	}
	defer db.Close()

	db.Exec("CREATE TABLE IF NOT Exists `t1` (`id` bigint(20) UNSIGNED NOT NULL, PRIMARY KEY (`id`) )")
	db.Exec("insert into t1 values (18446744073709551615)")

	var i = ^uint64(0)

	rows, err := db.Query("select id from t1 where id=?", i)
	if err != nil {
		log.Fatal(err)
	}
	defer rows.Close()

	var r uint64
	for rows.Next() {
		rows.Scan(&r)
		fmt.Printf("GOT: %d \n", r)
	}

	rows, err = db.Query("select id from t1 where id=?", -1)
	if err != nil {
		log.Fatal(err)
	}
	defer rows.Close()

	for rows.Next() {
		rows.Scan(&r)
		fmt.Printf("GOT: %d \n", r)
	}
}

2. What did you expect to see?

run against MySQL it returns

GOT: 18446744073709551615

3. What did you see instead?

run against TiDB it returns:

GOT: 18446744073709551615
GOT: 18446744073709551615

4. What version of TiDB are you using (tidb-server -V or run select tidb_version(); on TiDB)?

Release Version: v3.0.0-beta.1-68-ge48b258f9
Git Commit Hash: e48b258f9226ed8d4e6147154afb26ab7d8c59b2
Git Branch: master
UTC Build Time: 2019-04-04 05:05:01
GoVersion: go version go1.12.1 darwin/amd64
Race Enabled: false
TiKV Min Version: 2.1.0-alpha.1-ff3dd160846b7d1aed9079c389fc188f7f5ea13e
Check Table Before Drop: false

related issue: go-sql-driver/mysql#838

[lysu]

Thanks for your feedback! @darren
It's a bug, we will take a look, and also welcome to issue PR if you interesting this :D