what is fastest: single selector or multiple

Question

Which one is fastest?

single selector

$('#main_body').find('[data-table="'+table+'"]:first > tbody > [data-id='+id+']:first');

$('#main_body').find('[data-table="'+table+'"]:first').children('tbody').children('[data-id='+id+':first]');

Possible duplicate of https://stackoverflow.com/questions/1003855/howto-benchmark-javascript-code — CBroe, Jul 31 '17 at 11:37
But before you start comparing which one of two ways to do the same thing is faster, you might want to make them actually do the same thing in the first place. `[data-id='+id+']:first` and `.children('[data-id='+id+']')` don’t select the same element(s). — CBroe, Jul 31 '17 at 11:39
`.children('[data-id='+id+':first]')` ... now you’re looking for elements with `data-id="123:first"` or sth. like that ;-) — CBroe, Jul 31 '17 at 11:42
Possible duplicate of https://stackoverflow.com/questions/17752874/multiple-selector-vs-single-selector-performance — , Jul 31 '17 at 11:45

score 1 · Accepted Answer · answered Jul 31 '17 at 11:45

1

For a direct answer, I suggest using tools like jsperf and do some test.

single selector   : 19,992 ±2.49% (ops/sec) fastest
multiple selectors: 16,035 ±3.91% (ops/sec) 21% slower

For a full answer and explanation, I presume the first will be always quicker because is a one function call agains three.

answered Jul 31 '17 at 11:45

gmo