I have tried before with another graphic generator http://parles.upf.edu/llocs/adljc/grafics.old/ and if you check those you will see that x axis labels are generated, not pretty well, but the labels are there because the data is actually there.
At the pie graphic you will see the labels have encoding issues, but they are there, could this be the reason for canvas not showing labels, my data is in utf-8 and words have accents…
Queries are the same, it’s only the way of generating the graphic that is different, it’s a php library: http://www.ebrueggeman.com/phpgraphlib
Actually, both graphics (phplib and canvasjs) are currently generated form the exact same data, I preffer canvas because it is visually better than the other.
So why could be json showing as null when the fields are actually not.