How To remove rows on specific columns

[#1]

Hi,

The above table is just an example of my data set. I have 100k rows and 500+ columns. My question is how to remove the "aaa" rows 

[#2 · Accepted solution]

I am not sure what you want the final result to be.  If you want the resulting table to be:

Names Default To Here( 1 );
dt = Current Data Table();

// Get all of the column names
colNameList = dt << get column names( string );

// Remove the first column name from the list
Remove From( colNameList, 1, 1 );

dt << Begin Data Update;

// Loop across all columns in the list and recode them
For( i = 1, i <= N Items( colNameList ), i++,
	dt << Recode Column(
		As Column( dt, colNameList[i] ),
		{Map Value( _rcOrig, {"aaa", " "}, Unmatched( _rcNow ) )},
		Update Properties( 1 ),
		Target Column( As Column( dt, colNameList[i] ) )
	)
);

dt << End Data Update;

If the final result is

Names Default To Here( 1 );
dt = Current Data Table();

// Get all of the column names
colNameList = dt << get column names( string );

// Remove the first column name from the list
Remove From( colNameList, 1, 1 );

// Loop across all columns in the list and find rows 
// that have aaa for that column
For( i = 1, i <= N Items( colNameList ), i++,
	dt << select where(
		As Column( dt, colNameList[i] ) == "aaa",
		current selection( "extend" )
	)
);

// Delete all selected rows
dt << delete rows;

For future discussions where you provide an image of a data table, please insert it as a table and not as a picture of the table, or if possible attach the table.  This will remove the requirement of the responder to have to spend the time required to individually create the table(s).