I use placeholders to import the sum of 4 numeric columns from Table A, to Table B using the string (otherwise placeholder does not function). This functions nicely, and I get table B drawn from these values (4 columns). However, when I try to display the columns of Table B (constructed with placeholders) in a bar chart, it does not work as bar graph could have only one column with strings for labels others must be number columns. If I convert the string columns to numeric, then the placeholders don't work.

Thank you Aleksandar. I followed your advise and created table B as a MySQL query table from table A. I got nicely the SUMS of the columns in one row. Any chance that I enter the second and third rows MANUALLY for e.g comparison of the figures from past years? In other words, could it be possible that a table based on MySQL query could have mixed rows: the first one generated by the MySQL query and the other rows generated manually? Or any chance that only one cell of a table receives the data using MySQL query while other cells get written manually?