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/ms >>> gid/influxdb/215c75a2-3837-4c60-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/ > msgid/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/CALGqCvPA1VYOGrizgJc-V7rZBfbNNYLfCJfMo%3D-OhJ_fCMerdg%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
