Description
Issue description
ENUM and SET column types cannot be identified. MySQL do not return MYSQL_TYPE_ENUM or MYSQL_TYPE_SET, so https://github.com/go-sql-driver/mysql/blob/master/fields.go#L34 and https://github.com/go-sql-driver/mysql/blob/master/fields.go#L73 do not catch those cases. Instead, MySQL set the flag field with ENUM_FLAG and SET_FLAG
Example code
package main
import (
"database/sql"
_ "github.com/go-sql-driver/mysql"
"log"
)
func main() {
conn, err := sql.Open("mysql", "root:@tcp(127.0.0.1)/mydb")
if err != nil {
log.Fatal(err)
}
_, err = conn.Exec("DROP TABLE IF EXISTS test")
if err != nil {
log.Fatal(err)
}
_, err = conn.Exec("CREATE TABLE `test` (`id` bigint PRIMARY KEY, `e` enum('', 'v1', 'v2'), `s` set('', 'v1', 'v2'))")
if err != nil {
log.Fatal(err)
}
if err != nil {
log.Fatal(err)
}
_, err = conn.Exec("INSERT INTO test VALUES (1, '', '')")
if err != nil {
log.Fatal(err)
}
rows, err := conn.Query("SELECT e, s FROM `test`")
if err != nil {
log.Fatal(err)
}
columnTypes, err := rows.ColumnTypes()
if err != nil {
log.Fatal(err)
}
for _, t := range columnTypes {
log.Printf("the type of column '%s': %s\n", t.Name(), t.DatabaseTypeName())
}
}The result of above code:
the type of column 'e': CHAR
the type of column 's': CHAR
This can be fixed with the following at https://github.com/go-sql-driver/mysql/blob/master/fields.go#L79:
case fieldTypeString:
if mf.flags&flagEnum != 0 {
return "ENUM"
} else if mf.flags&flagSet != 0 {
return "SET"
}
if mf.charSet == binaryCollationID {
return "BINARY"
}The result after suggested fix:
the type of column 'e': ENUM
the type of column 's': SET
If this fix is not the correct way to address this issue, I would like to request an interface to expose the enum and set flag info.
Configuration
Driver version (or git SHA): v1.7.1
Go version: go1.21.1
Server version: MySQL 8.1.0
Server OS: MacOS 14.1.1