q lang - How do I add several columns at once in kdb? -

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Anyhow, I can only find examples showing how to add a column.

So I wrote this code, which works, but I know that there is a better way to do this: the table exists with the column already filled with data, and add new columns to me Which are initially zero. 

  T: Update column 1: `t; T: Update column 2: `t from; T: Update column 3: `t; T: Update column 4: `t from;   
 I tried to create a function like this:  
  colNames: `column1` column2`column3`column4; T: {update x: `each colNamesList;   
 But it only adds one column and it's called X.  
 Any suggestions to improve this code will greatly appreciate. I just have to add a lot more than 4 columns and my code is very long. Thanks!   
 
 
 Several ways to get it ....  
  Newcols: `col3`col4; Q) @ [Tab; Newcale;:;]] call 1 call 2 coal 3 coal 4 ------------------- a1b2c3   
 Also can specify different types  
  q) @ [tab; Newcomers ;: (`; 0N)] col1 col2 col3 col4 ------------- ------ a 1b2c3   
 or Make a functional update  
  q)! [`Tab; (); 0b; Newcols! Count [newcols] #enlist (), `]` tab

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