需要手动在Glue连接中指定SQL Server实例的数据库引擎端点。在JDBC URL中，SQL Server实例名称将被忽略掉，所以需要显式地指定数据库引擎端点。以下是示例代码：

val connectionName = "myJdbcConnection"
val jdbcDriverClass = "com.microsoft.sqlserver.jdbc.SQLServerDriver"
val databaseName = "myDatabase"
val dbInstanceIdentifier = "myDbInstance"
val connectionString = s"jdbc:sqlserver://$dbInstanceIdentifier.$AWS_REGION.rds.amazonaws.com:1433;database=$databaseName"

val jdbcOptions = Map(
  "url" -> connectionString,
  "driver" -> jdbcDriverClass,
  "user" -> "username",
  "password" -> "password"
)

val myDf = spark.read.options(jdbcOptions).jdbc(connectionName, "myTable")