Supossed我有一個管道像這樣使用CrossValidator培訓NaiveBayes模型得到精密/召回: val tokenizer = new Tokenizer().setInputCol("tweet").setOutputCol("words")
val hashingTF = new HashingTF().setNumFeatures(1000).setInputCol("wo
鑑於dataframes df_a和df_b,我怎麼能達到同樣的效果左排除加盟: SELECT df_a.*
FROM df_a
LEFT JOIN df_b
ON df_a.id = df_b.id
WHERE df_b.id is NULL
我已經試過: df_a.join(df_b, df_a("id")===df_b("id"), "left")
.s