I find the syntax for RethinkDB filtering a little unintuitive – if this was actually Javascript, you might expect to see “row[‘Query’]”. I expect this allows them to instrument the queries more easily, although considering they are supposedly translating this into an intermediate language, this doesn’t seem necessary.<\/p>\n
To do equality, non-equality, and so on, there are several functions available (ne \/ eq \/ gt \/ lt). I suspect that the reason for this is that the getter function for a column always returns an object – so it can’t be “equal” to null. This is likely a Builder pattern that lets them lazy-execute results; if this database goes the direction of Oracle’s optimizer it will also provide opportunities for query rewriting.<\/p>\n
The key is, using Javascript operators will be syntactically correct, but will not work. Unfortunately the RethinkDB editor does not warn you about this, or auto-correct them.<\/p>\n
\nr.db('performance')\n.table('query_timings')\n.filter(\n function(d){ \n return d('Query').ne(null) \n }) \n<\/pre>\nHopefully in the future we’ll also see ES6 functions, to make this more compact.<\/p>\n","protected":false},"excerpt":{"rendered":"
I find the syntax for RethinkDB filtering a little unintuitive – if this was actually Javascript, you might expect to see “row[‘Query’]”. I expect this allows them to instrument the queries more easily, although considering they are supposedly translating this into an intermediate language, this doesn’t seem necessary. To do equality, non-equality, and so on, … <\/p>\n