Spark DataFrame show() is used to display the contents of the DataFrame in a Table Row & Column Format. By default, it shows only 20 Rows and the column values are truncated at 20 characters.
1. Spark DataFrame show() Syntax & Example
1.1 Syntax
def show()
def show(numRows : scala.Int)
def show(truncate : scala.Boolean)
def show(numRows : scala.Int, truncate : scala.Boolean)
def show(numRows : scala.Int, truncate : scala.Int)
def show(numRows : scala.Int, truncate : scala.Int, vertical : scala.Boolean)
1.2 Example
import spark.implicits._
val columns = Seq("Seqno","Quote")
val data = Seq(("1", "Be the change that you wish to see in the world"),
("2", "Everyone thinks of changing the world, but no one thinks of changing himself."),
("3", "The purpose of our lives is to be happy."),
("4", "Be cool."))
val df = data.toDF(columns:_*)
df.show()
//+-----+--------------------+
//|Seqno| Quote|
//+-----+--------------------+
//| 1|Be the change tha...|
//| 2|Everyone thinks o...|
//| 3|The purpose of ou...|
//| 4| Be cool.|
//+-----+--------------------+
As you see above, values in the Quote column is truncated at 20 characters, Let’s see how to display the full column contents.
//Display full column contents
df.show(false)
//+-----+-----------------------------------------------------------------------------+
//|Seqno|Quote |
//+-----+-----------------------------------------------------------------------------+
//|1 |Be the change that you wish to see in the world |
//|2 |Everyone thinks of changing the world, but no one thinks of changing himself.|
//|3 |The purpose of our lives is to be happy. |
//|4 |Be cool. |
//+-----+-----------------------------------------------------------------------------+
By default show() method displays only 20 rows from DataFrame. The below example limits the rows to 2 and full column contents. Our DataFrame has just 4 rows hence I can’t demonstrate with more than 4 rows. If you have a DataFrame with thousands of rows try changing the value from 2 to 100 to display more than 20 rows.
// Display 2 rows and full column contents
df.show(2,false)
//+-----+-----------------------------------------------------------------------------+
//|Seqno|Quote |
//+-----+-----------------------------------------------------------------------------+
//|1 |Be the change that you wish to see in the world |
//|2 |Everyone thinks of changing the world, but no one thinks of changing himself.|
//+-----+-----------------------------------------------------------------------------+
You can also truncate the column value at the desired length.
// Display 2 rows & column values 25 characters
df.show(2,25)
//+-----+-------------------------+
//|Seqno| Quote|
//+-----+-------------------------+
//| 1|Be the change that you...|
//| 2|Everyone thinks of cha...|
//+-----+-------------------------+
//only showing top 2 rows
Finally, let’s see how to display the DataFrame vertically record by record.
// Display DataFrame rows & columns vertically
df.show(3,25,true)
//-RECORD 0--------------------------
// Seqno | 1
// Quote | Be the change that you...
//-RECORD 1--------------------------
// Seqno | 2
// Quote | Everyone thinks of cha...
//-RECORD 2--------------------------
// Seqno | 3
// Quote | The purpose of our liv...
Happy Learning !!
