Tags are not valid for functions in InfluxQL. There is no way to pass "hosts" to COUNT(). You will not be able to graph a count of hosts in Grafana without post-processing of the data.
On Wed, Sep 28, 2016 at 9:48 AM, Paul Letskii <[email protected]> wrote: > Thank you all for advices. > > I think, I have to give more details about my situation. > > InfluxDB 1.0; Telegraf 1.0 > > I have Telegraf collecting metrics from a servers and pulling it into > InfluxDB. I use this InfluxDB as datasource for Grafana. > Mem is a standard measurement. It has "hosts" in tags. > > > What I want: I want to count hosts. So, if it was ordinary SQL, I can do > something like SELECT COUNT("hosts") FROM mem. > > SHOW TAG VALUES FROM mem WITH KEY = "host" do the trick, but I need to get > it in Grafana. And there is no SHOW, only SELECT. > > > > On Wednesday, September 28, 2016 at 6:15:37 PM UTC+3, Sean Beckett wrote: >> >> Do you have a field key named "value"? I was giving examples, but without >> access to your schema I can't give actual queries. However, the SHOW TAG >> VALUES FROM mem_usage_percent WITH KEY = "host" query gives you what you >> want. Did you try that? >> >> On Wed, Sep 28, 2016 at 5:35 AM, Paul Letskii <[email protected]> wrote: >> >>> I'm still getting empty result: >>> >>> SELECT "host", "value" FROM mem WHERE time < now() - 2m >>> >>> Success! (no results to display) >>> >>> My goal is to count number of hosts and get this number into Grafana. >>> >>> >>> >>> On Tuesday, September 27, 2016 at 6:41:30 PM UTC+3, Sean Beckett wrote: >>>> >>>> That is because "host" is a tag >>>> <https://docs.influxdata.com/influxdb/v1.0/concepts/glossary/#tag>, >>>> not a field >>>> <https://docs.influxdata.com/influxdb/v1.0/concepts/glossary/#field>. >>>> SELECT statements must include at least one field. >>>> >>>> If you want only the values of "host", that's a SHOW >>>> <https://docs.influxdata.com/influxdb/v1.0/query_language/schema_exploration/#explore-tag-values-with-show-tag-values> >>>> query, not a SELECT >>>> <https://docs.influxdata.com/influxdb/v1.0/query_language/data_exploration/#the-select-statement-and-the-where-clause> >>>> query: >>>> >>>> SHOW TAG VALUES FROM mem_usage_percent WITH KEY = "host" >>>> >>>> Note that the SHOW query does not accept a "WHERE time" clause. To get >>>> hosts during a particular time, use a SELECT query with a field as well: >>>> >>>> SELECT "host", "value" FROM mem_usage_percent WHERE time > ... >>>> >>>> >>>> >>>> On Tue, Sep 27, 2016 at 12:04 AM, Paul Letskii <[email protected]> >>>> wrote: >>>> >>>>> Ok. But how have I change this query: "SELECT "host" FROM >>>>> "mem_usage_percent"" to get just hosts field? >>>>> According to documentation it is correct query ( >>>>> https://docs.influxdata.com/influxdb/v1.0/query_language/da >>>>> ta_exploration/#the-select-statement-and-the-where-clause) >>>>> >>>>> >>>>> On Monday, September 26, 2016 at 6:00:06 PM UTC+3, Sean Beckett wrote: >>>>>> >>>>>> Every SELECT statement must have at least one field. You selecting >>>>>> only a tag. Use either "SHOW TAG VALUES" or include a field in the query. >>>>>> >>>>>> On Mon, Sep 26, 2016 at 6:55 AM, Paul Letskii <[email protected]> >>>>>> wrote: >>>>>> >>>>>>> Hi all! >>>>>>> >>>>>>> InfluxDB version 1.0\ >>>>>>> >>>>>>> I'm trying to get list of hosts from measurement >>>>>>> "mem_usage_percent". >>>>>>> >>>>>>> This query works: >>>>>>> SELECT * FROM "mem_usage_percent" >>>>>>> >>>>>>> This one doesn't: >>>>>>> SELECT "host" FROM "mem_usage_percent" >>>>>>> Accordingly to documentation it has to. >>>>>>> >>>>>>> My final goal is to count number of unique hosts. Like: SELECT >>>>>>> count("host") FROM "mem_usage_percent" >>>>>>> >>>>>>> What is correct syntax to get information from certain field? >>>>>>> >>>>>>> Thank you in advance! >>>>>>> >>>>>>> Best regards, >>>>>>> Paul Letskii >>>>>>> >>>>>>> -- >>>>>>> Remember to include the InfluxDB version number with all issue >>>>>>> reports >>>>>>> --- >>>>>>> You received this message because you are subscribed to the Google >>>>>>> Groups "InfluxDB" group. >>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>> send an email to [email protected]. >>>>>>> To post to this group, send email to [email protected]. >>>>>>> Visit this group at https://groups.google.com/group/influxdb. >>>>>>> To view this discussion on the web visit >>>>>>> https://groups.google.com/d/msgid/influxdb/f3c71013-7e8c-4fd >>>>>>> b-9808-0b1fb35e9052%40googlegroups.com >>>>>>> <https://groups.google.com/d/msgid/influxdb/f3c71013-7e8c-4fdb-9808-0b1fb35e9052%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>>>> . >>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>> >>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> Sean Beckett >>>>>> Director of Support and Professional Services >>>>>> InfluxDB >>>>>> >>>>> -- >>>>> Remember to include the InfluxDB version number with all issue reports >>>>> --- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "InfluxDB" group. >>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>> an email to [email protected]. >>>>> To post to this group, send email to [email protected]. >>>>> Visit this group at https://groups.google.com/group/influxdb. >>>>> To view this discussion on the web visit >>>>> https://groups.google.com/d/msgid/influxdb/215c75a2-3837-4c6 >>>>> 0-b5bd-14bb26f74fbe%40googlegroups.com >>>>> <https://groups.google.com/d/msgid/influxdb/215c75a2-3837-4c60-b5bd-14bb26f74fbe%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>> . >>>>> >>>>> For more options, visit https://groups.google.com/d/optout. >>>>> >>>> >>>> >>>> >>>> -- >>>> Sean Beckett >>>> Director of Support and Professional Services >>>> InfluxDB >>>> >>> -- >>> Remember to include the InfluxDB version number with all issue reports >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "InfluxDB" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> To post to this group, send email to [email protected]. >>> Visit this group at https://groups.google.com/group/influxdb. >>> To view this discussion on the web visit https://groups.google.com/d/ms >>> gid/influxdb/38bc648d-1930-47ee-bef9-62112bba5a00%40googlegroups.com >>> <https://groups.google.com/d/msgid/influxdb/38bc648d-1930-47ee-bef9-62112bba5a00%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> >> >> -- >> Sean Beckett >> Director of Support and Professional Services >> InfluxDB >> > -- > Remember to include the InfluxDB version number with all issue reports > --- > You received this message because you are subscribed to the Google Groups > "InfluxDB" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/influxdb. > To view this discussion on the web visit https://groups.google.com/d/ > msgid/influxdb/f5a8354f-745e-48eb-9322-852ee6d7cbc3%40googlegroups.com > <https://groups.google.com/d/msgid/influxdb/f5a8354f-745e-48eb-9322-852ee6d7cbc3%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > For more options, visit https://groups.google.com/d/optout. > -- Sean Beckett Director of Support and Professional Services InfluxDB -- Remember to include the InfluxDB version number with all issue reports --- You received this message because you are subscribed to the Google Groups "InfluxDB" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/influxdb. To view this discussion on the web visit https://groups.google.com/d/msgid/influxdb/CALGqCvMo9oGQS45bSUy9AXf85JEKsxydF12q%3DsTU%3DoVb0wGK%3DQ%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
