I am trying to iterate through the entire parquet file but I only need one element from each row group. Is there a way to extract only a single row in a row group without reading the entire row group at every iteration?
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I have a range of data that needs to be sorted (example: B3:D1000) but I want to ignore 1 specific row (example: row B370). Is there a way to write a SORTN function to sort the data while ignoring that one specific row?
Trying to avoid writing a separate FILTER function if possible.
To leave out row 370 and show the rest of the data sorted by column B, use this:
=sort( filter(B3:D, row(B3:D) <> 370) )
I am using this technique to concatenate a list of values per group. Before grouping I sorted the group field and the value field in ascending order.
this is the result after concatenating (column [Custom]):
In a following step I expand one column of the table in the last column, causing the [Custom] column to change sorting... ???
This is the content of the dd_center_tbi_variable column:
I have two text files with only one column each.
I need to take the column from each of the text files and create a new text file with the two columns with tabs.
These columns have no relation (ID) but are in order with each other.
I could do that in Excel, but there are more than 200 thousand lines and not accepted.
How can I do it in Pentaho?
Take 2 text input steps, read both the files,
after that add 2 add constant step create same column with some value,make sure the value of the both constant values remains same.
use stream lookup/merge join and merge them with constant values.
generate the file.
You can read both files with Text file input, add "row number" in each stream, which gives you two streams of 2 fields each. Then you can Merge join both streams on Row number, and finally a Select fields step to clean up the output so that only the two relevant fields are kept. Then Text file output to write it.
To count the rows of csv file we can use Get Files Rows Count Input in etl. How to find the number columns of a csv file?
Just read the first row of the CSV file using Text-File-Input setting header rows to 0. Usually, the first row contains field names. If you read the whole row into a single field, you can use Split-Field-To-Rows to have a single fieldname per row and the number of rows tells you the number of fields. There are other ways, but this one easily prepares for a subsequent metadata injection - if that's what you have in mind.
No Need of Metadata injection , In Split-Field-To-Rows, check "Include rownum in output" and give some name to that Variable. Then apply sort rows on that Variable, use Sample rows, then you will get number of fields which are present in the file.
I have a CSV file called input_sheet.csv and the content in the file is:
Coulmn1,Coulmn2,Coulmn3,Coulmn4,Coulmn5,Coulmn6,Coulmn7,Coulmn8
Data1,Data2,Data3,Data4,Data5,Data6,Data7,Data8
Value1,Value2,Value3,Value4,Value5,Value6,Value7,Value8
I am reading the rows one by one in while loop and in each row i want to change "Nth" column value based on my requirement.
For example:1st row 6th column,2nd row 5th column.
Could you please help out with some solution?
Thanks in advance.