I want to copy some columns from csv file to cassandra table. There's 300 columns in csv file and I only need the first ten columns. There's no header in the csv file.
I tried
copy table from 'file.csv' with header=false and skipcols=[range(11,300)]
but it didn't work.
Can you specify column names after table name i.e.
COPY TABLE xx(c1,c2..C30) FROM ..
Related
I have been trying to add additional column in parquet file through copy activity pipeline to copy from csv file to parquet
but it is giving me error the column name is invalid. Column name cannot contain these character:[,;{}()\n\t=]
I am adding only filename as column name in additional column at source and taking $$filepath as value.
I reproduced the above and got the same error.
The above error occurs when we give special characters (,;{}()\n\t=) in the column name of the additional column. For Parquet file special characters not allowed for columns names.
When we avoid the above special characters in the column name, we can get desired result.
Parquet file:
So I've successfully imported a csv file as a data frame df
I need to compare successive rows to see which row in the 'Mass' column has the closest value to 20 and then save the entire content of the closest row in a list/any other format.
Any ideas on how I should go about doing this?
I have 2 excel files with single sheet,there have same column name,one column name id is 'name'.I need to merge the second file data in the first file,and the 'name' row data in second file have to put the last row with the same 'name' row in the first file. How can I do it?
Thanks in advance. first file second file final file
I have a specific column in a csv file and I want to write each row of that column as a newline in the same txt file. I'm using Panda if that helps. I can't quite figure out how to iterate over the rows of one specific column.
This should work:
dataframe[colname].to_csv('filepath.txt', sep="\n", index=False)
add header = False if you don't need the column name in that .txt file
I want to import a multicolumn .csv file into Excel. But my aim is to import them with reversed order; e.g. I want the last row of the .csv file be the first in my Excel and the first row of the .csv file be the last row in my Excel. I like something like a macro or an advanced filter for this task.
My .csv contains around 14000 rows so I can't use any manual tricks.
Import data in usual way
Add/insert an extra column to the imported data
Populate the extra column using Series Fill so that it contains the values 1,2,3,...
Select all data (imported and the extra column) and sort on the values in the extra column in descending order
Delete the extra column - data will now be sorted as you require.