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How to show full column content in a Spark Dataframe?

I am using spark-csv to load data into a DataFrame. I want to do a simple query and display the content:

val df = sqlContext.read.format("com.databricks.spark.csv").option("header", "true").load("my.csv")
df.registerTempTable("tasks")
results = sqlContext.sql("select col from tasks");
results.show()

The col seems truncated:

scala> results.show();
+--------------------+
|                 col|
+--------------------+
|2015-11-16 07:15:...|
|2015-11-16 07:15:...|
|2015-11-16 07:15:...|
|2015-11-16 07:15:...|
|2015-11-16 07:15:...|
|2015-11-16 07:15:...|
|2015-11-16 07:15:...|
|2015-11-16 07:15:...|
|2015-11-16 07:15:...|
|2015-11-16 07:15:...|
|2015-11-16 07:15:...|
|2015-11-16 07:15:...|
|2015-11-16 07:15:...|
|2015-11-16 07:15:...|
|2015-11-16 07:15:...|
|2015-11-06 07:15:...|
|2015-11-16 07:15:...|
|2015-11-16 07:21:...|
|2015-11-16 07:21:...|
|2015-11-16 07:21:...|
+--------------------+

How do I show the full content of the column?


G
GreenGiant

results.show(20, false) will not truncate. Check the source

20 is the default number of rows displayed when show() is called without any arguments.


Not OP but this is indeed the right answer : Minor correction, boolean should be False, not false.
It would be "False" in python, but "false" in scala/java
it's false (not False) in spark-shell
the equivalent for writing to stream in console mode is dataFrame.writeStream.outputMode("append").format("console").option("truncate", "false").start()
what is so special about 20? Why 20?
S
Shubham Chaudhary

If you put results.show(false) , results will not be truncated


I imagine that the comment on TomTom101's answer about false applies here, too.
@Narendra Parmar the syntax should be results.show(20, False). The one you have mentioned will give error.
@ Jai Prakash , i have given this answer for scala and you are talking about python,
@NarendraParmar sorry you are correct. In scala both the options are valid. results.show(false) and results.show(20, false)
M
MoeChen

Below code would help to view all rows without truncation in each column

df.show(df.count(), False)

same questio i asked the prior answerer: does this cause df to be collected twice?
@javadba yes, I think count() will go through df once, and show() will collect df twice.
As an alternative, you could give a very large number as the first parameter instead of df.count() in order to save on the requirement to persist. For example, if the row count of df is 1000, you could do df.show(1000000, false) and it will work. Tried the following and it worked: scala> println(df.count) res2: Long = 987 scala> df.show(990)
c
codeaperature

The other solutions are good. If these are your goals:

No truncation of columns, No loss of rows, Fast and Efficient

These two lines are useful ...

    df.persist
    df.show(df.count, false) // in Scala or 'False' in Python

By persisting, the 2 executor actions, count and show, are faster & more efficient when using persist or cache to maintain the interim underlying dataframe structure within the executors. See more about persist and cache.


Very nice. Thanks!
S
Sai

results.show(20, False) or results.show(20, false) depending on whether you are running it on Java/Scala/Python


R
RaHuL VeNuGoPaL

In Pyspark we can use

df.show(truncate=False) this will display the full content of the columns without truncation.

df.show(5,truncate=False) this will display the full content of the first five rows.


f
farrellw

The following answer applies to a Spark Streaming application.

By setting the "truncate" option to false, you can tell the output sink to display the full column.

val query = out.writeStream
          .outputMode(OutputMode.Update())
          .format("console")
          .option("truncate", false)
          .trigger(Trigger.ProcessingTime("5 seconds"))
          .start()

B
Baglay Vyacheslav

In c# Option("truncate", false) does not truncate data in the output.

StreamingQuery query = spark
                    .Sql("SELECT * FROM Messages")
                    .WriteStream()
                    .OutputMode("append")
                    .Format("console")
                    .Option("truncate", false)
                    .Start();

O
OneCricketeer

results.show(false) will show you the full column content.

Show method by default limit to 20, and adding a number before false will show more rows.


I
Ignacio Alorre

Within Databricks you can visualize the dataframe in a tabular format. With the command:

display(results)

It will look like

https://i.stack.imgur.com/g0Svi.png


z
zero323

results.show(20,false) did the trick for me in Scala.


D
Djihane AKROUM

Try df.show(20,False)

Notice that if you do not specify the number of rows you want to show, it will show 20 rows but will execute all your dataframe which will take more time !


e
epic_last_song

try this command :

df.show(df.count())

Try this: df.show(some no) will work but df.show(df.count()) will not work df.count gives output type long which is not accepted by df.show() as it accept integer type.
Example use df.show(2000). It will retrieve 2000 rows
does this cause df to be collected twice?
o
onemanarmy

Tried this in pyspark

df.show(truncate=0)

n
ngenne

In Spark Pythonic way, remember:

if you have to display data from a dataframe, use show(truncate=False) method.

else if you have to display data from a Stream dataframe view (Structured Streaming), use the writeStream.format("console").option("truncate", False).start() methods with option.

Hope it could helps someone.


K
KeepLearning

I use the plugin Chrome extension works pretty well:

[https://userstyles.org/styles/157357/jupyter-notebook-wide][1]


P
Pritesh Kumar

Try this in scala:

df.show(df.count.toInt, false)

The show method accepts an integer and a Boolean value but df.count returns Long...so type casting is required


S
Sarath Subramanian

PYSPARK

In the below code, df is the name of dataframe. 1st parameter is to show all rows in the dataframe dynamically rather than hardcoding a numeric value. The 2nd parameter will take care of displaying full column contents since the value is set as False.

df.show(df.count(),False)

https://i.stack.imgur.com/Lu6Dv.png

SCALA

In the below code, df is the name of dataframe. 1st parameter is to show all rows in the dataframe dynamically rather than hardcoding a numeric value. The 2nd parameter will take care of displaying full column contents since the value is set as false.

df.show(df.count().toInt,false)

https://i.stack.imgur.com/Bv9Kw.png