Select max common Date from differents DataFrames (Scala Spark) - scala

I have differents dataframes and I want to select the max common Date of these DF. For example, I have the following dataframes:
+--------------+-------+
|Date | value |
+--------------+-------+
|2015-12-14 |5 |
|2017-11-19 |1 |
|2016-09-02 |1 |
|2015-12-14 |3 |
|2015-12-14 |1 |
+--------------+-------+
|Date | value |
+--------------+-------+
|2015-12-14 |5 |
|2017-11-19 |1 |
|2016-09-02 |1 |
|2015-12-14 |3 |
|2015-12-14 |1 |
+--------------+-------+
|Date | value |
+--------------+-------+
|2015-12-14 |5 |
|2012-12-21 |1 |
|2016-09-02 |1 |
|2015-12-14 |3 |
|2015-12-14 |1 |
The selected date would be 2016-09-02 because is the max date that exists in these 3 DF (the date 2017-11-19 is not in the third DF).
I am trying to do it with agg(max) but in this way I just have the highest date of a DataFrame:
df1.select("Date").groupBy("Date").agg(max("Date))
Thanks in advance!

You can do semi joins to get the common dates, and aggregate the maximum date. No need to group by date because you want to get its maximum.
val result = df1.join(df2, Seq("Date"), "left_semi").join(df3, Seq("Date"), "left_semi").agg(max("Date"))
You can also use intersect:
val result = df1.select("Date").intersect(df2.select("Date")).intersect(df3.select("Date")).agg(max("Date"))

Related

spark sql max function not producing right value

I'm trying to find the max of a column grouped by spark partition id. I'm getting the wrong value when applying the max function though. Here is the code:
val partitionCol = uuid()
val localRankCol = "test"
df = df.withColumn(partitionCol, spark_partition_id)
val windowSpec = WindowSpec.partitionBy(partitionCol).orderBy(sortExprs:_*)
val rankDF = df.withColumn(localRankCol, dense_rank().over(windowSpec))
val rankRangeDF = rankDF.agg(max(localRankCol))
rankRangeDF.show(false)
sortExprs is applying an ascending sort on sales.
And the result with some dummy data is (partitionCol is 5th column):
+--------------+------+-----+---------------------------------+--------------------------------+----+
|title |region|sales|r6bea781150fa46e3a0ed761758a50dea|5683151561af407282380e6cf25f87b5|test|
+--------------+------+-----+---------------------------------+--------------------------------+----+
|Die Hard |US |100.0|1 |0 |1 |
|Rambo |US |100.0|1 |0 |1 |
|Die Hard |AU |200.0|1 |0 |2 |
|House of Cards|EU |400.0|1 |0 |3 |
|Summer Break |US |400.0|1 |0 |3 |
|Rambo |EU |100.0|1 |1 |1 |
|Summer Break |APAC |200.0|1 |1 |2 |
|Rambo |APAC |300.0|1 |1 |3 |
|House of Cards|US |500.0|1 |1 |4 |
+--------------+------+-----+---------------------------------+--------------------------------+----+
+---------+
|max(test)|
+---------+
|5 |
+---------+
"test" column has a max value of 4 but 5 is being returned.

create unique runid and append in output dataframe for each time we run spark scala code

create unique runid and append in output dataframe for each time we run spark scala code
Below is my Output dataframe i want to add 1 more column for runid , can anyone help?
+--------+-------------------------------+---+
|order_id|Diff |id |
+--------+-------------------------------+---+
|12 |order_status |1 |
|1 |order_customer_id order_status |1 |
|68885 |New row in DataFrame 2 |1 |
|68886 |New row in DataFrame 2 |1 |
|2 |order_customer_id |1 |
|12 |order_status |2 |
|1 |order_customer_id order_status |2 |
|68885 |New row in DataFrame 2 |2 |
|68886 |New row in DataFrame 2 |2 |
|2 |order_customer_id |2 |
+--------+-------------------------------+---+

Delete values lower than cummax on multiple spark dataframe columns in scala

I am having a data frame as shown below. The number of signals are more than 100, so there will be more than 100 columns in the data frame.
+---+------------+--------+--------+--------+
|id | date|signal01|signal02|signal03|......
+---+------------+--------+--------+--------+
|050|2021-01-14 |1 |3 |1 |
|050|2021-01-15 |null |4 |2 |
|050|2021-02-02 |2 |3 |3 |
|051|2021-01-14 |1 |3 |0 |
|051|2021-01-15 |2 |null |null |
|051|2021-02-02 |3 |3 |2 |
|051|2021-02-03 |1 |3 |1 |
|052|2021-03-03 |1 |3 |0 |
|052|2021-03-05 |3 |3 |null |
|052|2021-03-06 |2 |null |2 |
|052|2021-03-16 |3 |5 |5 |.......
+-------------------------------------------+
I have to find out cummax of each signal and then compare with respective signal columns and delete the signal records which are having value lower than cummax and null values.
step1. find cumulative max for each signal with respect to id column.
step2. delete the records which are having lower value than cummax for each signal.
step3. Take count of records which are having cummax less than signal value(excluded of null) for each signals with respect to id.
After the count the final output should be as shown below.
+---+------------+--------+--------+--------+
|id | date|signal01|signal02|signal03|.....
+---+------------+--------+--------+--------+
|050|2021-01-14 |1 | 3 | 1 |
|050|2021-01-15 |null | null | 2 |
|050|2021-02-02 |2 | 3 | 3 |
|
|051|2021-01-14 |1 | 3 | 0 |
|051|2021-01-15 |2 | null | null |
|051|2021-02-02 |3 | 3 | 2 |
|051|2021-02-03 |null | 3 | null |
|
|052|2021-03-03 |1 | 3 | 0 |
|052|2021-03-05 |3 | 3 | null |
|052|2021-03-06 |null | null | 2 |
|052|2021-03-16 |3 | 5 | 5 | ......
+----------------+--------+--------+--------+
I have tried by using window function as below and it worked for almost all records.
val w = Window.partitionBy("id").orderBy("date").rowsBetween(Window.unboundedPreceding, Window.currentRow)
val signalList01 = ListBuffer[Column]()
signalList01.append(col("id"), col("date"))
for (column <- signalColumns) {
// Applying the max non null aggregate function on each signal column
signalList01 += (col(column), max(column).over(w).alias(column+"_cummax")) }
val cumMaxDf = df.select(signalList01: _*)
But I am getting error values as shown below for few records.
Is there any idea about how this error records in the cummax column? Any leads appreciated!
Just giving out hints here (as you suggested) to help you unblock the situation, but --WARNING-- haven't tested the code !
the code you provided in the comments looks good. It'll get you your max column
val nw_df = original_df.withColumn("singal01_cummax", sum(col("singal01")).over(windowCodedSO))
now, you need to be able to compare the two values in "singal01" and "singal01_cummax". A function like this, maybe:
def takeOutRecordsLessThanCummax (signal:Int, singal_cummax: Int) : Any =
{ if (signal == null || signal < singal_cummax) null
else singal_cummax }
since we'll be applying it to columns, we'll wrap it up in a UDF
val takeOutRecordsLessThanCummaxUDF : UserDefinedFunction = udf {
(i:Int, j:Int) => takeOutRecordsLessThanCummax(i,j)
}
and then, you can combine everything above so it can be applicable on your original dataframe. Something like this could work:
val signal_cummax_suffix = "_cummax"
val result = original_df.columns.foldLeft(original_df)(
(dfac, colname) => dfac
.withColumn(colname.concat(signal_cummax_suffix),
sum(col(colname)).over(windowCodedSO))
.withColumn(colname.concat("output"),
takeOutRecordsLessThanCummaxUDF(col(colname), col(colname.concat(signal_cummax_suffix))))
)

Replace the values based on condition spark

I have dataset I want to replace the result column based on the least value of quantity by grouping id,date
id,date,quantity,result
1,2016-01-01,245,1
1,2016-01-01,345,3
1,2016-01-01,123,2
1,2016-01-02,120,5
2,2016-01-01,567,1
2,2016-01-01,568,1
2,2016-01-02,453,1
Here the output, replace the quantity which has least value in that groupby(id,date). Here ordering of rows doesn't matter, any order it can be.
id,date,quantity,result
1,2016-01-01,245,2
1,2016-01-01,345,2
1,2016-01-01,123,2
1,2016-01-02,120,5
2,2016-01-01,567,1
2,2016-01-01,568,1
2,2016-01-02,453,1
Use the Window and get the maximum by max.
import pyspark.sql.functions as f
from pyspark.sql import Window
w = Window.partitionBy('id', 'date')
df.withColumn('result', f.when(f.col('quantity') == f.min('quantity').over(w), f.col('result'))) \
.withColumn('result', f.max('result').over(w)).show(10, False)
+---+----------+--------+------+
|id |date |quantity|result|
+---+----------+--------+------+
|1 |2016-01-02|120 |5 |
|1 |2016-01-01|245 |2 |
|1 |2016-01-01|345 |2 |
|1 |2016-01-01|123 |2 |
|2 |2016-01-02|453 |1 |
|2 |2016-01-01|567 |1 |
|2 |2016-01-01|568 |1 |
+---+----------+--------+------+

How to find the next occurring item from current row in a data frame using Spark Windowing?

I have the following Dataframe:
+------+----------+-------------+--------------------+---------+-----+----------+
|ID |MEM_ID | BFS | SVC_DT |TYP |SEQ |BFS_SEQ |
+------+----------+----------------------------------+---------+-----+----------+
|105771|29378668 | BRIMONIDINE | 2019-02-04 00:00:00|PD |1 |1 |
|105772|29378668 | BRIMONIDINE | 2019-04-04 00:00:00|PD |2 |2 |
|105773|29378668 | BRIMONIDINE | 2019-04-17 00:00:00|RV |3 |3 |
|105774|29378668 | TIMOLOL | 2019-04-17 00:00:00|RV |4 |1 |
|105775|29378668 | BRIMONIDINE | 2019-04-22 00:00:00|PD |5 |4 |
|105776|29378668 | TIMOLOL | 2019-04-22 00:00:00|PD |6 |2 |
+------+----------+----------------------------------+---------+-----+----------+
For every row, I have to find the occurrence of next 'PD' Typ at BFS level from the current row and populate its associated ID as a new column named 'NEXT_PD_TYP_ID'
The output I am expecting is:
+------+---------+-------------+--------------------+----+-----+---------+---------------+
|ID |MEM_ID | BFS | SVC_DT |TYP |SEQ |BFS_SEQ |NEXT_PD_TYP_ID |
+------+---------+----------------------------------+----+-----+---------+---------------+
|105771|29378668 | BRIMONIDINE | 2019-02-04 00:00:00|PD |1 |1 |105772 |
|105772|29378668 | BRIMONIDINE | 2019-04-04 00:00:00|PD |2 |2 |105775 |
|105773|29378668 | BRIMONIDINE | 2019-04-17 00:00:00|RV |3 |3 |105775 |
|105774|29378668 | TIMOLOL | 2019-04-17 00:00:00|RV |4 |1 |105776 |
|105775|29378668 | BRIMONIDINE | 2019-04-22 00:00:00|PD |5 |4 |null |
|105776|29378668 | TIMOLOL | 2019-04-22 00:00:00|PD |6 |2 |null |
+------+---------+----------------------------------+----+-----+---------+---------------+
Need help.
I have tried using the conditional aggregation: max(when), however since it has more than one 'PD' the max is returning only one value for all the rows.
No error messages
I hope this helps.
I created a new column with ID's of TYP === PD. I called it TYPPDID.
Then I used Window frame ranging from next row to unbounded following row and got the first not-null TYPPDID
orderBy("ID") in the end is only to show records in order.
import org.apache.spark.sql.functions._
val df = Seq(
("105771", "BRIMONIDINE", "PD"),
("105772", "BRIMONIDINE", "PD"),
("105773", "BRIMONIDINE","RV"),
("105774", "TIMOLOL", "RV"),
("105775", "BRIMONIDINE", "PD"),
("105776", "TIMOLOL", "PD")
).toDF("ID", "BFS", "TYP").withColumn("TYPPDID", when($"TYP" === "PD", $"ID"))
df: org.apache.spark.sql.DataFrame = [ID: string, BFS: string ... 2 more fields]
scala> df.show
+------+-----------+---+-------+
| ID| BFS|TYP|TYPPDID|
+------+-----------+---+-------+
|105771|BRIMONIDINE| PD| 105771|
|105772|BRIMONIDINE| PD| 105772|
|105773|BRIMONIDINE| RV| null|
|105774| TIMOLOL| RV| null|
|105775|BRIMONIDINE| PD| 105775|
|105776| TIMOLOL| PD| 105776|
+------+-----------+---+-------+
scala> val overColumns = Window.partitionBy("BFS").orderBy("ID").rowsBetween(1, Window.unboundedFollowing)
overColumns: org.apache.spark.sql.expressions.WindowSpec = org.apache.spark.sql.expressions.WindowSpec#eb923ef
scala> df.withColumn("NEXT_PD_TYP_ID",first("TYPPDID", true).over(overColumns)).orderBy("ID").show(false)
+------+-----------+---+-------+-------+
|ID |BFS |TYP|TYPPDID|NEXT_PD_TYP_ID|
+------+-----------+---+-------+-------+
|105771|BRIMONIDINE|PD |105771 |105772 |
|105772|BRIMONIDINE|PD |105772 |105775 |
|105773|BRIMONIDINE|RV |null |105775 |
|105774|TIMOLOL |RV |null |105776 |
|105775|BRIMONIDINE|PD |105775 |null |
|105776|TIMOLOL |PD |105776 |null |
+------+-----------+---+-------+-------+