title: Joining two dataframes without a common column
body: <p>I have two dataframes which has different types of columns. I need to join those two different dataframe. Please refer the below example</p>
  <pre><code>val df1 has
  Customer_name 
  Customer_phone
  Customer_age
  
  val df2 has
  Order_name
  Order_ID
  </code></pre>
  <p>These two dataframe doesn't have any common column. Number of rows and Number of columns in the two dataframes also differs. I tried to insert a new dummy column to increase the row_index value as below
  val dfr=df1.withColumn(&quot;row_index&quot;,monotonically_increasing_id()).</p>
  <p>But as i am using Spark 2, monotonically_increasing_id method is not supported. Is there any way to join two dataframe, so that I can create the value of two dataframe in a single sheet of excel file.</p>
  <p>For example</p>
  <pre><code>val df1:
  Customer_name  Customer_phone  Customer_age
  karti           9685684551     24      
  raja            8595456552     22
  
  val df2:
  Order_name Order_ID
  watch       1
  cattoy     2
  </code></pre>
  <p>My final excel sheet should be like this:</p>
  <pre><code>Customer_name  Customer_phone  Customer_age   Order_name  Order_ID
  
  karti          9685684551      24             watch        1
     
  raja           8595456552      22             cattoy      2
  </code></pre>