Description
Issue description
When connecting to a database using compress=true, any use of DB.Ping() seems to cause subsequent queries to not return rows.
Ping itself does not return an error.
Example code
package main
import (
"database/sql"
"fmt"
_ "github.com/go-sql-driver/mysql"
)
func main() {
db, err := sql.Open("mysql", "root:mypw@tcp(127.0.0.1:3306)/?compress=1")
if err != nil {
panic(err)
}
defer db.Close()
if err = db.Ping(); err != nil {
panic("Ping error: " + err.Error())
}
var version string
query := "SELECT @@global.version"
err = db.QueryRow(query).Scan(&version)
if err != nil {
panic("QueryRow error: " + err.Error())
}
fmt.Println(version)
}Error log
panic: QueryRow error: sql: no rows in result set
If I replace the call to QueryRow with Query and a loop over rows, the loop does not execute (there are no rows, even though selecting a global variable should always result in 1 row).
If I change compress=1 to compress=0, the code works properly and prints the server version.
Alternatively, if I comment-out the Ping call, the code works properly.
Configuration
Driver version (or git SHA): 1.9.2
Go version: go version go1.24.4 darwin/arm64
Server version: Tested with both MySQL 8.0.40 and MariaDB 11.4.5, same behavior with both
Server OS: Linux (VM via Docker Desktop for Mac) - MySQL was on Oracle Linux, MariaDB was on Debian