Spark dataframe row count Spark Count is an action that results in the number of rows available in a DataFrame. Examples. count ¶ DataFrame. There are a few ways to solve pyspark. Changed in version 3. Parquet files store counts in the file footer, so Spark doesn't need to read all the rows in the file and actually perform the count, it can Jun 30, 2025 · How do you add a new column with row number (using row_number) to the PySpark DataFrame? pyspark. first, Dataframe. If you can live without exact count then you can use Dataframe. To run the SQL query, use spark. It stores statistics so count results are fast (in seconds). count () method is used to use the count of the DataFrame. DataFrame. count() is enough, because you have selected distinct ticket_id in the lines above. Oct 26, 2023 · This tutorial explains how to add a new column to a PySpark DataFrame that contains row numbers, including an example. head(<number of rows>) etc to compensate for your needs. count() → int ¶ Returns the number of rows in this DataFrame. count # DataFrame. Apr 17, 2025 · Diving Straight into Counting Rows in a PySpark DataFrame Need to know how many rows are in your PySpark DataFrame—like customer records or event logs—to validate data or monitor an ETL pipeline? Counting the number of rows in a DataFrame is a core skill for data engineers working with Apache Spark. sql() function; it also returns a DataFrame. count() [source] # Returns the number of rows in this DataFrame. 3. 6. df. I needed to get unique number ID for each row in DataFrame. It's easier for Spark to perform counts on Parquet files than CSV/JSON files. count() returns the number of rows in the dataframe. sql. Sep 6, 2016 · The time it takes to count the records in a DataFrame depends on the power of the cluster and how the data is stored. row_number() [source] # Window function: returns a sequential number starting at 1 within a window partition. window module provides functions like row_number (), rank (), and dense_rank () to add ranking-based columns to a DataFrame. The row_number () assigns unique sequential numbers to rows within specified partitions and orderings, rank () provides a ranking with tied values receiving the same rank If you need exact count then use parquet or delta lake format to store the data. But there are a few different approaches for using count(), each with their own nuances: select() agg() groupBy() In this comprehensive guide, you‘ll learn how to use these three methods for counting rows in PySpark DataFrames using hands-on examples. com Jul 23, 2025 · In this article, we will discuss how to get the number of rows and the number of columns of a PySpark dataframe. Also it returns an integer - you can't call distinct on an integer. window module provides a set of functions like row_number (), rank (), and dense_rank () to add a column with row number. Sep 5, 2025 · In PySpark, the row_number () window function in PySpark is used to return a new column containing a unique sequential number to each row based on a specified order. It does not take any parameters, such as column names. In this article, I’ve explained the concept of window functions, syntax, and finally how to use them with PySpark SQL and PySpark DataFrame API. Among them, row_number() assigns a unique sequential number to each row based on the ordering specified in a window specification, whereas rank() assigns the same rank Jun 29, 2021 · In this article, we will discuss how to count rows based on conditions in Pyspark dataframe. count (): This function is used to extract number of rows from the Dataframe. Sep 23, 2025 · PySpark Window functions are used to calculate results, such as the rank, row number, etc. The PySpark count() function provides an easy way to get these row counts from a DataFrame. It differs from sample (random subset) by providing a precise tally and leverages Spark’s optimizations over RDD operations like count () on RDDs, focusing on scalar pyspark. New in version 1. 0: Supports Spark Connect. The pyspark. For this, we are going to use these methods: Using where () function. May 13, 2024 · To count the number of rows in a DataFrame using SQL syntax, you can execute a SQL query with the COUNT function. functions. Oct 29, 2018 · Creating a row number of each row in PySpark DataFrame using row_number () function with Spark version 2. isEmpty, Dataframe. pyspark. Performance optimizations can make Spark counts very quick. Count vs Other DataFrame Operations The count operation returns the total row count as an integer, unlike groupBy (). 0. Creating Dataframe for demonstration: Mar 16, 2024 · Spark is very powerful for Big Data processing and its power requires developer to write code carefully. For finding the number of rows and number of columns we will use count () and columns () with len () function respectively. count () (grouped counts as a DataFrame), collect (all rows as a list), or take (limited rows as a list). , over a range of input rows. 4. 2 Asked 7 years ago Modified 1 year, 10 months ago Viewed 63k times Jul 3, 2025 · How to add a new column with a row number to a PySpark DataFrame without partitioning? The pyspark. Mar 27, 2024 · The spark. row_number # pyspark. Using filter () function. See full list on sparkbyexamples. Dec 28, 2020 · Just doing df_ua. window module provides functions like row_number(), rank (), and dense_rank () to add ranking-based columns to a DataFrame. esdusn lnpa rgkn ooyj hqewo yclaox hen jkd ovf ncsmmo xdeji wqb xifwfw tdldt ctmokw