A constructor that automatically analyzes the logical plan.
A constructor that automatically analyzes the logical plan.
This reports error eagerly as the DataFrame is constructed, unless SQLConf.dataFrameEagerAnalysis is turned off.
Aggregates on the entire DataFrame without groups.
Aggregates on the entire DataFrame without groups. {{ // df.agg(...) is a shorthand for df.groupBy().agg(...) df.agg(max($"age"), avg($"salary")) df.groupBy().agg(max($"age"), avg($"salary")) }}
(Java-specific) Aggregates on the entire DataFrame without groups.
(Java-specific) Aggregates on the entire DataFrame without groups. {{ // df.agg(...) is a shorthand for df.groupBy().agg(...) df.agg(Map("age" -> "max", "salary" -> "avg")) df.groupBy().agg(Map("age" -> "max", "salary" -> "avg")) }}
(Scala-specific) Aggregates on the entire DataFrame without groups.
(Scala-specific) Aggregates on the entire DataFrame without groups. {{ // df.agg(...) is a shorthand for df.groupBy().agg(...) df.agg(Map("age" -> "max", "salary" -> "avg")) df.groupBy().agg(Map("age" -> "max", "salary" -> "avg")) }}
(Scala-specific) Compute aggregates by specifying a map from column name to aggregate methods.
(Scala-specific) Compute aggregates by specifying a map from column name to aggregate methods. The resulting DataFrame will also contain the grouping columns.
The available aggregate methods are avg
, max
, min
, sum
, count
.
// Selects the age of the oldest employee and the aggregate expense for each department df.groupBy("department").agg( "age" -> "max", "expense" -> "sum" )
Selects column based on the column name and return it as a Column.
(Scala-specific) Returns a new DataFrame with an alias set.
Returns a new DataFrame with an alias set.
Selects column based on the column name and return it as a Column.
Returns an array that contains all of Rows in this DataFrame.
Returns a Java list that contains all of Rows in this DataFrame.
Returns all column names as an array.
Returns the number of rows in the DataFrame.
Save this RDD to a JDBC database at url
under the table name table
.
Save this RDD to a JDBC database at url
under the table name table
.
This will run a CREATE TABLE
and a bunch of INSERT INTO
statements.
If you pass true
for allowExisting
, it will drop any table with the
given name; if you pass false
, it will throw if the table already
exists.
Returns a new DataFrame that contains only the unique rows from this DataFrame.
Returns all column names and their data types as an array.
Returns a new DataFrame containing rows in this frame but not in another frame.
Returns a new DataFrame containing rows in this frame but not in another frame.
This is equivalent to EXCEPT
in SQL.
Only prints the physical plan to the console for debugging purpose.
Prints the plans (logical and physical) to the console for debugging purpose.
(Scala-specific) Returns a new DataFrame where a single column has been expanded to zero or more rows by the provided function.
(Scala-specific) Returns a new DataFrame where a single column has been expanded to zero
or more rows by the provided function. This is similar to a LATERAL VIEW
in HiveQL. All
columns of the input row are implicitly joined with each value that is output by the function.
df.explode("words", "word")(words: String => words.split(" "))
(Scala-specific) Returns a new DataFrame where each row has been expanded to zero or more rows by the provided function.
(Scala-specific) Returns a new DataFrame where each row has been expanded to zero or more
rows by the provided function. This is similar to a LATERAL VIEW
in HiveQL. The columns of
the input row are implicitly joined with each row that is output by the function.
The following example uses this function to count the number of books which contain a given word:
case class Book(title: String, words: String) val df: RDD[Book] case class Word(word: String) val allWords = df.explode('words) { case Row(words: String) => words.split(" ").map(Word(_)) } val bookCountPerWord = allWords.groupBy("word").agg(countDistinct("title"))
Filters rows using the given SQL expression.
Filters rows using the given SQL expression.
peopleDf.filter("age > 15")
Filters rows using the given condition.
Filters rows using the given condition.
// The following are equivalent: peopleDf.filter($"age" > 15) peopleDf.where($"age" > 15) peopleDf($"age" > 15)
Returns the first row.
Returns the first row. Alias for head().
Returns a new RDD by first applying a function to all rows of this DataFrame, and then flattening the results.
Applies a function f
to all rows.
Applies a function f
to all rows.
Applies a function f to each partition of this DataFrame.
Groups the DataFrame using the specified columns, so we can run aggregation on them.
Groups the DataFrame using the specified columns, so we can run aggregation on them. See GroupedData for all the available aggregate functions.
This is a variant of groupBy that can only group by existing columns using column names (i.e. cannot construct expressions).
// Compute the average for all numeric columns grouped by department. df.groupBy("department").avg() // Compute the max age and average salary, grouped by department and gender. df.groupBy($"department", $"gender").agg(Map( "salary" -> "avg", "age" -> "max" ))
Groups the DataFrame using the specified columns, so we can run aggregation on them.
Groups the DataFrame using the specified columns, so we can run aggregation on them. See GroupedData for all the available aggregate functions.
// Compute the average for all numeric columns grouped by department. df.groupBy($"department").avg() // Compute the max age and average salary, grouped by department and gender. df.groupBy($"department", $"gender").agg(Map( "salary" -> "avg", "age" -> "max" ))
Returns the first row.
Returns the first n
rows.
:: Experimental :: Adds the rows from this RDD to the specified table.
:: Experimental :: Adds the rows from this RDD to the specified table. Throws an exception if the table already exists.
:: Experimental :: Adds the rows from this RDD to the specified table, optionally overwriting the existing data.
:: Experimental :: Adds the rows from this RDD to the specified table, optionally overwriting the existing data.
Save this RDD to a JDBC database at url
under the table name table
.
Save this RDD to a JDBC database at url
under the table name table
.
Assumes the table already exists and has a compatible schema. If you
pass true
for overwrite
, it will TRUNCATE
the table before
performing the INSERT
s.
The table must already exist on the database. It must have a schema
that is compatible with the schema of this RDD; inserting the rows of
the RDD in order via the simple statement
INSERT INTO table VALUES (?, ?, ..., ?)
should not fail.
Returns a new DataFrame containing rows only in both this frame and another frame.
Returns a new DataFrame containing rows only in both this frame and another frame.
This is equivalent to INTERSECT
in SQL.
Returns true if the collect
and take
methods can be run locally
(without any Spark executors).
Returns the content of the DataFrame as a JavaRDD of Rows.
Converts a JavaRDD to a PythonRDD.
Converts a JavaRDD to a PythonRDD.
Join with another DataFrame, using the given join expression.
Join with another DataFrame, using the given join expression. The following performs
a full outer join between df1
and df2
.
// Scala: import org.apache.spark.sql.functions._ df1.join(df2, $"df1Key" === $"df2Key", "outer") // Java: import static org.apache.spark.sql.functions.*; df1.join(df2, col("df1Key").equalTo(col("df2Key")), "outer");
Right side of the join.
Join expression.
One of: inner
, outer
, left_outer
, right_outer
, semijoin
.
Inner join with another DataFrame, using the given join expression.
Inner join with another DataFrame, using the given join expression.
// The following two are equivalent: df1.join(df2, $"df1Key" === $"df2Key") df1.join(df2).where($"df1Key" === $"df2Key")
Cartesian join with another DataFrame.
Cartesian join with another DataFrame.
Note that cartesian joins are very expensive without an extra filter that can be pushed down.
Right side of the join operation.
Returns a new DataFrame by taking the first n
rows.
Returns a new RDD by applying a function to all rows of this DataFrame.
Returns a new RDD by applying a function to all rows of this DataFrame.
Returns a new RDD by applying a function to each partition of this DataFrame.
Returns a new RDD by applying a function to each partition of this DataFrame.
Returns a new DataFrame sorted by the given expressions.
Returns a new DataFrame sorted by the given expressions.
This is an alias of the sort
function.
Returns a new DataFrame sorted by the given expressions.
Returns a new DataFrame sorted by the given expressions.
This is an alias of the sort
function.
Prints the schema to the console in a nice tree format.
Returns the content of the DataFrame as an RDD of Rows.
Registers this RDD as a temporary table using the given name.
Registers this RDD as a temporary table using the given name. The lifetime of this temporary table is tied to the SQLContext that was used to create this DataFrame.
Returns a new DataFrame that has exactly numPartitions
partitions.
Returns a new DataFrame by sampling a fraction of rows, using a random seed.
Returns a new DataFrame by sampling a fraction of rows, using a random seed.
Sample with replacement or not.
Fraction of rows to generate.
Returns a new DataFrame by sampling a fraction of rows.
Returns a new DataFrame by sampling a fraction of rows.
Sample with replacement or not.
Fraction of rows to generate.
Seed for sampling.
:: Experimental :: (Scala-specific) Saves the contents of this DataFrame based on the given data source, SaveMode specified by mode, and a set of options
:: Experimental :: (Scala-specific) Saves the contents of this DataFrame based on the given data source, SaveMode specified by mode, and a set of options
:: Experimental :: Saves the contents of this DataFrame based on the given data source, SaveMode specified by mode, and a set of options.
:: Experimental :: Saves the contents of this DataFrame based on the given data source, SaveMode specified by mode, and a set of options.
:: Experimental :: Saves the contents of this DataFrame to the given path based on the given data source and SaveMode specified by mode.
:: Experimental :: Saves the contents of this DataFrame to the given path based on the given data source and SaveMode specified by mode.
:: Experimental :: Saves the contents of this DataFrame to the given path based on the given data source, using SaveMode.ErrorIfExists as the save mode.
:: Experimental :: Saves the contents of this DataFrame to the given path based on the given data source, using SaveMode.ErrorIfExists as the save mode.
:: Experimental :: Saves the contents of this DataFrame to the given path and SaveMode specified by mode, using the default data source configured by spark.
:: Experimental :: Saves the contents of this DataFrame to the given path and SaveMode specified by mode, using the default data source configured by spark.sql.sources.default.
:: Experimental :: Saves the contents of this DataFrame to the given path, using the default data source configured by spark.
:: Experimental :: Saves the contents of this DataFrame to the given path, using the default data source configured by spark.sql.sources.default and SaveMode.ErrorIfExists as the save mode.
Saves the contents of this DataFrame as a parquet file, preserving the schema.
Saves the contents of this DataFrame as a parquet file, preserving the schema.
Files that are written out using this method can be read back in as a DataFrame
using the parquetFile
function in SQLContext.
:: Experimental :: (Scala-specific) Creates a table from the the contents of this DataFrame based on a given data source, SaveMode specified by mode, and a set of options.
:: Experimental :: (Scala-specific) Creates a table from the the contents of this DataFrame based on a given data source, SaveMode specified by mode, and a set of options.
Note that this currently only works with DataFrames that are created from a HiveContext as
there is no notion of a persisted catalog in a standard SQL context. Instead you can write
an RDD out to a parquet file, and then register that file as a table. This "table" can then
be the target of an insertInto
.
:: Experimental :: Creates a table at the given path from the the contents of this DataFrame based on a given data source, SaveMode specified by mode, and a set of options.
:: Experimental :: Creates a table at the given path from the the contents of this DataFrame based on a given data source, SaveMode specified by mode, and a set of options.
Note that this currently only works with DataFrames that are created from a HiveContext as
there is no notion of a persisted catalog in a standard SQL context. Instead you can write
an RDD out to a parquet file, and then register that file as a table. This "table" can then
be the target of an insertInto
.
:: Experimental :: Creates a table at the given path from the the contents of this DataFrame based on a given data source, SaveMode specified by mode, and a set of options.
:: Experimental :: Creates a table at the given path from the the contents of this DataFrame based on a given data source, SaveMode specified by mode, and a set of options.
Note that this currently only works with DataFrames that are created from a HiveContext as
there is no notion of a persisted catalog in a standard SQL context. Instead you can write
an RDD out to a parquet file, and then register that file as a table. This "table" can then
be the target of an insertInto
.
:: Experimental :: Creates a table at the given path from the the contents of this DataFrame based on a given data source and a set of options, using SaveMode.ErrorIfExists as the save mode.
:: Experimental :: Creates a table at the given path from the the contents of this DataFrame based on a given data source and a set of options, using SaveMode.ErrorIfExists as the save mode.
Note that this currently only works with DataFrames that are created from a HiveContext as
there is no notion of a persisted catalog in a standard SQL context. Instead you can write
an RDD out to a parquet file, and then register that file as a table. This "table" can then
be the target of an insertInto
.
:: Experimental :: Creates a table from the the contents of this DataFrame, using the default data source configured by spark.
:: Experimental :: Creates a table from the the contents of this DataFrame, using the default data source configured by spark.sql.sources.default and SaveMode.ErrorIfExists as the save mode.
Note that this currently only works with DataFrames that are created from a HiveContext as
there is no notion of a persisted catalog in a standard SQL context. Instead you can write
an RDD out to a parquet file, and then register that file as a table. This "table" can then
be the target of an insertInto
.
:: Experimental :: Creates a table from the the contents of this DataFrame.
:: Experimental :: Creates a table from the the contents of this DataFrame. It will use the default data source configured by spark.sql.sources.default. This will fail if the table already exists.
Note that this currently only works with DataFrames that are created from a HiveContext as
there is no notion of a persisted catalog in a standard SQL context. Instead you can write
an RDD out to a parquet file, and then register that file as a table. This "table" can then
be the target of an insertInto
.
Returns the schema of this DataFrame.
Selects a set of columns.
Selects a set of columns. This is a variant of select
that can only select
existing columns using column names (i.e. cannot construct expressions).
// The following two are equivalent: df.select("colA", "colB") df.select($"colA", $"colB")
Selects a set of expressions.
Selects a set of expressions.
df.select($"colA", $"colB" + 1)
Selects a set of SQL expressions.
Selects a set of SQL expressions. This is a variant of select
that accepts
SQL expressions.
df.selectExpr("colA", "colB as newName", "abs(colC)")
Displays the top 20 rows of DataFrame in a tabular form.
Displays the DataFrame in a tabular form.
Displays the DataFrame in a tabular form. For example:
year month AVG('Adj Close) MAX('Adj Close) 1980 12 0.503218 0.595103 1981 01 0.523289 0.570307 1982 02 0.436504 0.475256 1983 03 0.410516 0.442194 1984 04 0.450090 0.483521
Number of rows to show
Returns a new DataFrame sorted by the given expressions.
Returns a new DataFrame sorted by the given expressions. For example:
df.sort($"col1", $"col2".desc)
Returns a new DataFrame sorted by the specified column, all in ascending order.
Returns a new DataFrame sorted by the specified column, all in ascending order.
// The following 3 are equivalent df.sort("sortcol") df.sort($"sortcol") df.sort($"sortcol".asc)
Returns the first n
rows in the DataFrame.
Returns a new DataFrame with columns renamed.
Returns a new DataFrame with columns renamed. This can be quite convenient in conversion from a RDD of tuples into a DataFrame with meaningful names. For example:
val rdd: RDD[(Int, String)] = ... rdd.toDF() // this implicit conversion creates a DataFrame with column name _1 and _2 rdd.toDF("id", "name") // this creates a DataFrame with column name "id" and "name"
Returns the object itself.
Returns the content of the DataFrame as a RDD of JSON strings.
Returns the content of the DataFrame as a JavaRDD of Rows.
Returns a new DataFrame containing union of rows in this frame and another frame.
Returns a new DataFrame containing union of rows in this frame and another frame.
This is equivalent to UNION ALL
in SQL.
Filters rows using the given condition.
Filters rows using the given condition. This is an alias for filter
.
// The following are equivalent: peopleDf.filter($"age" > 15) peopleDf.where($"age" > 15) peopleDf($"age" > 15)
Returns a new DataFrame by adding a column.
Returns a new DataFrame with a column renamed.
Left here for backward compatibility.
Left here for backward compatibility.
(Since version use toDF) 1.3.0
:: Experimental :: A distributed collection of data organized into named columns.
A DataFrame is equivalent to a relational table in Spark SQL. There are multiple ways to create a DataFrame:
Once created, it can be manipulated using the various domain-specific-language (DSL) functions defined in: DataFrame (this class), Column, and functions.
To select a column from the data frame, use
apply
method in Scala andcol
in Java.Note that the Column type can also be manipulated through its various functions.
A more concrete example in Scala:
and in Java: