package main
import (
"context"
"crypto/tls"
"fmt"
"log"
"github.com/ClickHouse/clickhouse-go/v2"
"github.com/ClickHouse/clickhouse-go/v2/lib/driver"
)
func main() {
conn, err := connect()
if err != nil {
panic(err)
}
ctx := context.Background()
rows, err := conn.Query(ctx, "SELECT name, toString(uuid) as uuid_str FROM system.tables LIMIT 5")
if err != nil {
log.Fatal(err)
}
defer rows.Close()
for rows.Next() {
var name, uuid string
if err := rows.Scan(&name, &uuid); err != nil {
log.Fatal(err)
}
log.Printf("name: %s, uuid: %s", name, uuid)
}
// 注意: rows.Err() のチェックを省略しないこと
if err := rows.Err(); err != nil {
log.Fatal(err)
}
}
func connect() (driver.Conn, error) {
var (
ctx = context.Background()
conn, err = clickhouse.Open(&clickhouse.Options{
Addr: []string{"<CLICKHOUSE_SECURE_NATIVE_HOSTNAME>:9440"},
Auth: clickhouse.Auth{
Database: "default",
Username: "default",
Password: "<DEFAULT_USER_PASSWORD>",
},
ClientInfo: clickhouse.ClientInfo{
Products: []struct {
Name string
Version string
}{
{Name: "an-example-go-client", Version: "0.1"},
},
},
Debugf: func(format string, v ...interface{}) {
fmt.Printf(format, v)
},
TLS: &tls.Config{
InsecureSkipVerify: true,
},
})
)
if err != nil {
return nil, err
}
if err := conn.Ping(ctx); err != nil {
if exception, ok := err.(*clickhouse.Exception); ok {
fmt.Printf("Exception [%d] %s \n%s\n", exception.Code, exception.Message, exception.StackTrace)
}
return nil, err
}
return conn, nil
}
