Explore your schema using InfluxQL
See the equivalent InfluxDB v2 documentation: Explore your data schema with Flux.
InfluxQL is an SQL-like query language for interacting with data in InfluxDB. The following sections cover useful query syntax for exploring your schema.
SHOW DATABASES | SHOW RETENTION POLICIES | SHOW SERIES |
SHOW MEASUREMENTS | SHOW TAG KEYS | SHOW TAG VALUES |
SHOW FIELD KEYS | Filter meta queries by time |
Sample data
The data used in this document are available for download on the Sample Data page.
Before proceeding, login to the Influx CLI.
$ influx -precision rfc3339
Connected to http://localhost:8086 version 1.11.8
InfluxDB shell 1.11.8
>
SHOW DATABASES
Returns a list of all databases on your instance.
Syntax
SHOW DATABASES
Examples
Run a SHOW DATABASES
query
> SHOW DATABASES
name: databases
name
----
NOAA_water_database
_internal
The query returns database names in a tabular format.
This InfluxDB instance has two databases: NOAA_water_database
and _internal
.
SHOW RETENTION POLICIES
Returns a list of retention policies for the specified database.
Syntax
SHOW RETENTION POLICIES [ON <database_name>]
Description of syntax
ON <database_name>
is optional.
If the query does not include ON <database_name>
, you must specify the
database with USE <database_name>
in the CLI or with the db
query
string parameter in the InfluxDB API request.
Examples
Run a SHOW RETENTION POLICIES
query with the ON
clause
> SHOW RETENTION POLICIES ON NOAA_water_database
name duration shardGroupDuration replicaN default
---- -------- ------------------ -------- -------
autogen 0s 168h0m0s 1 true
The query returns the list of retention policies in the NOAA_water_database
database in tabular format.
The database has one retention policy called autogen
.
The autogen
retention policy has an infinite duration,
a seven-day shard group duration,
a replication factor
of one, and it is the DEFAULT
retention policy for the database.
Run a SHOW RETENTION POLICIES
query without the ON
clause
Specify the database with USE <database_name>
> USE NOAA_water_database
Using database NOAA_water_database
> SHOW RETENTION POLICIES
name duration shardGroupDuration replicaN default
---- -------- ------------------ -------- -------
autogen 0s 168h0m0s 1 true
Specify the database with the db
query string parameter:
~# curl -G "http://localhost:8086/query?db=NOAA_water_database&pretty=true" --data-urlencode "q=SHOW RETENTION POLICIES"
{
"results": [
{
"statement_id": 0,
"series": [
{
"columns": [
"name",
"duration",
"shardGroupDuration",
"replicaN",
"default"
],
"values": [
[
"autogen",
"0s",
"168h0m0s",
1,
true
]
]
}
]
}
]
}
SHOW SERIES
Returns a list of series for the specified database.
Syntax
SHOW SERIES [ON <database_name>] [FROM_clause] [WHERE <tag_key> <operator> [ '<tag_value>' | <regular_expression>]] [LIMIT_clause] [OFFSET_clause]
Description of syntax
ON <database_name>
is optional.
If the query does not include ON <database_name>
, you must specify the
database with USE <database_name>
in the CLI or with the db
query
string parameter in the InfluxDB API request.
SHOW SERIES
only returns series in the database’s default retention policy,
and fails if there is no default retention policy.
The FROM
, WHERE
, LIMIT
, and OFFSET
clauses are optional.
The WHERE
clause supports tag comparisons; field comparisons are not
valid for the SHOW SERIES
query.
Supported operators in the WHERE
clause:
=
equal to
<>
not equal to
!=
not equal to
=~
matches against
!~
doesn’t match against
See the Data Exploration page for documentation on the
FROM
clause,
LIMIT
clause,
OFFSET
clause,
and on Regular Expressions in Queries.
Examples
Run a SHOW SERIES
query with the ON
clause
// Returns series for all shards in the database and default retention policy
> SHOW SERIES ON NOAA_water_database
key
---
average_temperature,location=coyote_creek
average_temperature,location=santa_monica
h2o_feet,location=coyote_creek
h2o_feet,location=santa_monica
h2o_pH,location=coyote_creek
h2o_pH,location=santa_monica
h2o_quality,location=coyote_creek,randtag=1
h2o_quality,location=coyote_creek,randtag=2
h2o_quality,location=coyote_creek,randtag=3
h2o_quality,location=santa_monica,randtag=1
h2o_quality,location=santa_monica,randtag=2
h2o_quality,location=santa_monica,randtag=3
h2o_temperature,location=coyote_creek
h2o_temperature,location=santa_monica
The query’s output is similar to the line protocol format.
Everything before the first comma is the measurement name.
Everything after the first comma is either a tag key or a tag value.
The NOAA_water_database
has five different measurements and 14 different series.
Run a SHOW SERIES
query without the ON
clause
Specify the database with USE <database_name>
> USE NOAA_water_database
Using database NOAA_water_database
> SHOW SERIES
key
---
average_temperature,location=coyote_creek
average_temperature,location=santa_monica
h2o_feet,location=coyote_creek
h2o_feet,location=santa_monica
h2o_pH,location=coyote_creek
h2o_pH,location=santa_monica
h2o_quality,location=coyote_creek,randtag=1
h2o_quality,location=coyote_creek,randtag=2
h2o_quality,location=coyote_creek,randtag=3
h2o_quality,location=santa_monica,randtag=1
h2o_quality,location=santa_monica,randtag=2
h2o_quality,location=santa_monica,randtag=3
h2o_temperature,location=coyote_creek
h2o_temperature,location=santa_monica
Specify the database with the db
query string parameter:
~# curl -G "http://localhost:8086/query?db=NOAA_water_database&pretty=true" --data-urlencode "q=SHOW SERIES"
{
"results": [
{
"statement_id": 0,
"series": [
{
"columns": [
"key"
],
"values": [
[
"average_temperature,location=coyote_creek"
],
[
"average_temperature,location=santa_monica"
],
[
"h2o_feet,location=coyote_creek"
],
[
"h2o_feet,location=santa_monica"
],
[
"h2o_pH,location=coyote_creek"
],
[
"h2o_pH,location=santa_monica"
],
[
"h2o_quality,location=coyote_creek,randtag=1"
],
[
"h2o_quality,location=coyote_creek,randtag=2"
],
[
"h2o_quality,location=coyote_creek,randtag=3"
],
[
"h2o_quality,location=santa_monica,randtag=1"
],
[
"h2o_quality,location=santa_monica,randtag=2"
],
[
"h2o_quality,location=santa_monica,randtag=3"
],
[
"h2o_temperature,location=coyote_creek"
],
[
"h2o_temperature,location=santa_monica"
]
]
}
]
}
]
}
Run a SHOW SERIES
query with several clauses
> SHOW SERIES ON NOAA_water_database FROM "h2o_quality" WHERE "location" = 'coyote_creek' LIMIT 2
key
---
h2o_quality,location=coyote_creek,randtag=1
h2o_quality,location=coyote_creek,randtag=2
The query returns all series in the NOAA_water_database
database that are
associated with the h2o_quality
measurement and the tag location = coyote_creek
.
The LIMIT
clause limits the number of series returned to two.
Run a SHOW SERIES
query limited by time
Limit series returned within a specified shard group duration.
// Returns all series in the current shard.
> SHOW SERIES ON NOAA_water_database WHERE time > now() - 1m
key
---
average_temperature,location=coyote_creek
h2o_feet,location=coyote_creek
h2o_pH,location=coyote_creek
h2o_quality,location=coyote_creek,randtag=1
h2o_quality,location=coyote_creek,randtag=2
h2o_quality,location=coyote_creek,randtag=3
h2o_temperature,location=coyote_creek
The query above returns all series in the NOAA_water_database
database in the current shard group. The WHERE
clause limits results to series in the shard group that contain a timestamp in the last minute. Note, if a shard group duration is 7 days, results returned may be up to 7 days old.
// Returns all series in shard groups that contain a timestamp in the last 28 days.
> SHOW SERIES ON NOAA_water_database WHERE time > now() - 28d
key
---
average_temperature,location=coyote_creek
average_temperature,location=santa_monica
h2o_feet,location=coyote_creek
h2o_feet,location=santa_monica
h2o_pH,location=coyote_creek
h2o_pH,location=santa_monica
h2o_quality,location=coyote_creek,randtag=1
h2o_quality,location=coyote_creek,randtag=2
h2o_quality,location=coyote_creek,randtag=3
h2o_quality,location=santa_monica,randtag=1
h2o_quality,location=santa_monica,randtag=2
h2o_quality,location=santa_monica,randtag=3
h2o_temperature,location=coyote_creek
h2o_temperature,location=santa_monica
Note, if the specified shard group duration is 7 days, the query above returns series for the last 3 or 4 shards.
SHOW MEASUREMENTS
Returns a list of measurements for the specified database.
Syntax
SHOW MEASUREMENTS [ON <database_name>] [WITH MEASUREMENT <operator> ['<measurement_name>' | <regular_expression>]] [WHERE <tag_key> <operator> ['<tag_value>' | <regular_expression>]] [LIMIT_clause] [OFFSET_clause]
Description of Syntax
ON <database_name>
is optional.
If the query does not include ON <database_name>
, you must specify the
database with USE <database_name>
in the CLI or with the db
query
string parameter in the InfluxDB API request.
The WITH
, WHERE
, LIMIT
and OFFSET
clauses are optional.
The WHERE
clause supports tag comparisons; field comparisons are not valid for the SHOW MEASUREMENTS
query.
Supported operators in the WHERE
clause:
=
equal to
<>
not equal to
!=
not equal to
=~
matches against
!~
doesn’t match against
See the Data Exploration page for documentation on the
LIMIT
clause,
OFFSET
clause,
and on Regular expressions in queries.
Examples
Run a SHOW MEASUREMENTS
query with the ON
clause
> SHOW MEASUREMENTS ON NOAA_water_database
name: measurements
name
----
average_temperature
h2o_feet
h2o_pH
h2o_quality
h2o_temperature
The query returns the list of measurements in the NOAA_water_database
database.
The database has five measurements: average_temperature
, h2o_feet
,
h2o_pH
, h2o_quality
, and h2o_temperature
.
Run a SHOW MEASUREMENTS
query without the ON
clause
Specify the database with USE <database_name>
> USE NOAA_water_database
Using database NOAA_water_database
> SHOW MEASUREMENTS
name: measurements
name
----
average_temperature
h2o_feet
h2o_pH
h2o_quality
h2o_temperature
Specify the database with the db
query string parameter:
~# curl -G "http://localhost:8086/query?db=NOAA_water_database&pretty=true" --data-urlencode "q=SHOW MEASUREMENTS"
{
{
"results": [
{
"statement_id": 0,
"series": [
{
"name": "measurements",
"columns": [
"name"
],
"values": [
[
"average_temperature"
],
[
"h2o_feet"
],
[
"h2o_pH"
],
[
"h2o_quality"
],
[
"h2o_temperature"
]
]
}
]
}
]
}
Run a SHOW MEASUREMENTS
query with several clauses (i)
> SHOW MEASUREMENTS ON NOAA_water_database WITH MEASUREMENT =~ /h2o.*/ LIMIT 2 OFFSET 1
name: measurements
name
----
h2o_pH
h2o_quality
The query returns the measurements in the NOAA_water_database
database that
start with h2o
.
The LIMIT
and OFFSET
clauses limit the number of measurement names returned to
two and offset the results by one, skipping the h2o_feet
measurement.
Run a SHOW MEASUREMENTS
query with several clauses (ii)
> SHOW MEASUREMENTS ON NOAA_water_database WITH MEASUREMENT =~ /h2o.*/ WHERE "randtag" =~ /\d/
name: measurements
name
----
h2o_quality
The query returns all measurements in the NOAA_water_database
that start
with h2o
and have values for the tag key randtag
that include an integer.
SHOW TAG KEYS
Returns a list of tag keys associated with the specified database.
Syntax
SHOW TAG KEYS [ON <database_name>] [FROM_clause] WITH KEY [ [<operator> "<tag_key>" | <regular_expression>] | [IN ("<tag_key1>","<tag_key2")]] [WHERE <tag_key> <operator> ['<tag_value>' | <regular_expression>]] [LIMIT_clause] [OFFSET_clause]
Description of syntax
ON <database_name>
is optional.
If the query does not include ON <database_name>
, you must specify the
database with USE <database_name>
in the CLI or with the db
query
string parameter in the InfluxDB API request.
The FROM
clause and the WHERE
clause are optional.
The WHERE
clause supports tag comparisons; field comparisons are not
valid for the SHOW TAG KEYS
query.
Supported operators in the WHERE
clause:
=
equal to
<>
not equal to
!=
not equal to
=~
matches against
!~
doesn’t match against
See the Data Exploration page for documentation on the
FROM
clause,
LIMIT
clause,
OFFSET
clause,
and on Regular Expressions in Queries.
Examples
Run a SHOW TAG KEYS
query with the ON
clause
> SHOW TAG KEYS ON "NOAA_water_database"
name: average_temperature
tagKey
------
location
name: h2o_feet
tagKey
------
location
name: h2o_pH
tagKey
------
location
name: h2o_quality
tagKey
------
location
randtag
name: h2o_temperature
tagKey
------
location
The query returns the list of tag keys in the NOAA_water_database
database.
The output groups tag keys by measurement name;
it shows that every measurement has the location
tag key and that the
h2o_quality
measurement has an additional randtag
tag key.
Run a SHOW TAG KEYS
query without the ON
clause
Specify the database with USE <database_name>
> USE NOAA_water_database
Using database NOAA_water_database
> SHOW TAG KEYS
name: average_temperature
tagKey
------
location
name: h2o_feet
tagKey
------
location
name: h2o_pH
tagKey
------
location
name: h2o_quality
tagKey
------
location
randtag
name: h2o_temperature
tagKey
------
location
Specify the database with the db
query string parameter:
~# curl -G "http://localhost:8086/query?db=NOAA_water_database&pretty=true" --data-urlencode "q=SHOW TAG KEYS"
{
"results": [
{
"statement_id": 0,
"series": [
{
"name": "average_temperature",
"columns": [
"tagKey"
],
"values": [
[
"location"
]
]
},
{
"name": "h2o_feet",
"columns": [
"tagKey"
],
"values": [
[
"location"
]
]
},
{
"name": "h2o_pH",
"columns": [
"tagKey"
],
"values": [
[
"location"
]
]
},
{
"name": "h2o_quality",
"columns": [
"tagKey"
],
"values": [
[
"location"
],
[
"randtag"
]
]
},
{
"name": "h2o_temperature",
"columns": [
"tagKey"
],
"values": [
[
"location"
]
]
}
]
}
]
}
Run a SHOW TAG KEYS
query with several clauses
> SHOW TAG KEYS ON "NOAA_water_database" FROM "h2o_quality" LIMIT 1 OFFSET 1
name: h2o_quality
tagKey
------
randtag
The query returns tag keys from the h2o_quality
measurement in the
NOAA_water_database
database.
The LIMIT
and OFFSET
clauses limit the number of tag keys returned to one
and offsets the results by one.
Run a SHOW TAG KEYS
query with a WITH KEY IN
clause
> SHOW TAG KEYS ON "telegraf" WITH KEY IN ("host","region")
"measurement","tagKey"
"cpu","host"
"cpu_load_short","host"
"cpu_load_short","region"
"disk","host"
"diskio","host"
"docker","host"
"docker_container_blkio","host"
"docker_container_cpu","host"
"docker_container_mem","host"
"docker_container_status","host"
SHOW TAG VALUES
Returns the list of tag values for the specified tag key(s) in the database.
Syntax
SHOW TAG VALUES [ON <database_name>][FROM_clause] WITH KEY [ [<operator> "<tag_key>" | <regular_expression>] | [IN ("<tag_key1>","<tag_key2")]] [WHERE <tag_key> <operator> ['<tag_value>' | <regular_expression>]] [LIMIT_clause] [OFFSET_clause]
Description of syntax
ON <database_name>
is optional.
If the query does not include ON <database_name>
, you must specify the
database with USE <database_name>
in the CLI or with the db
query string parameter in the InfluxDB API request.
The WITH
clause is required.
It supports specifying a single tag key, a regular expression, and multiple tag keys.
The FROM
, WHERE
, LIMIT
, and OFFSET
clauses are optional.
The WHERE
clause supports tag comparisons; field comparisons are not
valid for the SHOW TAG KEYS
query.
Supported operators in the WITH
and WHERE
clauses:
=
equal to
<>
not equal to
!=
not equal to
=~
matches against
!~
doesn’t match against
See the Data Exploration page for documentation on the
FROM
clause,
LIMIT
clause,
OFFSET
clause,
and on Regular Expressions in Queries.
Examples
Run a SHOW TAG VALUES
query with the ON
clause
> SHOW TAG VALUES ON "NOAA_water_database" WITH KEY = "randtag"
name: h2o_quality
key value
--- -----
randtag 1
randtag 2
randtag 3
The query returns all tag values of the randtag
tag key in the NOAA_water_database
database.
SHOW TAG VALUES
groups query results by measurement name.
Run a SHOW TAG VALUES
query without the ON
clause
Specify the database with USE <database_name>
> USE NOAA_water_database
Using database NOAA_water_database
> SHOW TAG VALUES WITH KEY = "randtag"
name: h2o_quality
key value
--- -----
randtag 1
randtag 2
randtag 3
Specify the database with the db
query string parameter:
~# curl -G "http://localhost:8086/query?db=NOAA_water_database&pretty=true" --data-urlencode 'q=SHOW TAG VALUES WITH KEY = "randtag"'
{
"results": [
{
"statement_id": 0,
"series": [
{
"name": "h2o_quality",
"columns": [
"key",
"value"
],
"values": [
[
"randtag",
"1"
],
[
"randtag",
"2"
],
[
"randtag",
"3"
]
]
}
]
}
]
}
Run a SHOW TAG VALUES
query with several clauses
> SHOW TAG VALUES ON "NOAA_water_database" WITH KEY IN ("location","randtag") WHERE "randtag" =~ /./ LIMIT 3
name: h2o_quality
key value
--- -----
location coyote_creek
location santa_monica
randtag 1
The query returns the tag values of the tag keys location
and randtag
for
all measurements in the NOAA_water_database
database where randtag
has tag values.
The LIMIT
clause limits the number of tag values returned to three.
SHOW FIELD KEYS
Returns the field keys and the data type of their field values.
Syntax
SHOW FIELD KEYS [ON <database_name>] [FROM <measurement_name>]
Description of syntax
ON <database_name>
is optional.
If the query does not include ON <database_name>
, you must specify the
database with USE <database_name>
in the CLI or with the db
query
string parameter in the InfluxDB API request.
The FROM
clause is also optional.
See the Data Exploration page for documentation on the
FROM
clause.
Note: A field’s data type can differ across shards. If your field has more than one type,
SHOW FIELD KEYS
returns the type that occurs first in the following list: float, integer, string, boolean.
Examples
Run a SHOW FIELD KEYS
query with the ON
clause
> SHOW FIELD KEYS ON "NOAA_water_database"
name: average_temperature
fieldKey fieldType
-------- ---------
degrees float
name: h2o_feet
fieldKey fieldType
-------- ---------
level description string
water_level float
name: h2o_pH
fieldKey fieldType
-------- ---------
pH float
name: h2o_quality
fieldKey fieldType
-------- ---------
index float
name: h2o_temperature
fieldKey fieldType
-------- ---------
degrees float
The query returns the field keys and field value data types for each
measurement in the NOAA_water_database
database.
Run a SHOW FIELD KEYS
query without the ON
clause
Specify the database with USE <database_name>
> USE NOAA_water_database
Using database NOAA_water_database
> SHOW FIELD KEYS
name: average_temperature
fieldKey fieldType
-------- ---------
degrees float
name: h2o_feet
fieldKey fieldType
-------- ---------
level description string
water_level float
name: h2o_pH
fieldKey fieldType
-------- ---------
pH float
name: h2o_quality
fieldKey fieldType
-------- ---------
index float
name: h2o_temperature
fieldKey fieldType
-------- ---------
degrees float
Specify the database with the db
query string parameter:
~# curl -G "http://localhost:8086/query?db=NOAA_water_database&pretty=true" --data-urlencode 'q=SHOW FIELD KEYS'
{
"results": [
{
"statement_id": 0,
"series": [
{
"name": "average_temperature",
"columns": [
"fieldKey",
"fieldType"
],
"values": [
[
"degrees",
"float"
]
]
},
{
"name": "h2o_feet",
"columns": [
"fieldKey",
"fieldType"
],
"values": [
[
"level description",
"string"
],
[
"water_level",
"float"
]
]
},
{
"name": "h2o_pH",
"columns": [
"fieldKey",
"fieldType"
],
"values": [
[
"pH",
"float"
]
]
},
{
"name": "h2o_quality",
"columns": [
"fieldKey",
"fieldType"
],
"values": [
[
"index",
"float"
]
]
},
{
"name": "h2o_temperature",
"columns": [
"fieldKey",
"fieldType"
],
"values": [
[
"degrees",
"float"
]
]
}
]
}
]
}
Run a SHOW FIELD KEYS
query with the FROM
clause
> SHOW FIELD KEYS ON "NOAA_water_database" FROM "h2o_feet"
name: h2o_feet
fieldKey fieldType
-------- ---------
level description string
water_level float
The query returns the fields keys and field value data types for the h2o_feet
measurement in the NOAA_water_database
database.
Common Issues with SHOW FIELD KEYS
SHOW FIELD KEYS and field type discrepancies
Field value
data types
cannot differ within a shard but they
can differ across shards.
SHOW FIELD KEYS
returns every data type, across every shard, associated with
the field key.
Example
The all_the_types
field stores four different data types:
> SHOW FIELD KEYS
name: mymeas
fieldKey fieldType
-------- ---------
all_the_types integer
all_the_types float
all_the_types string
all_the_types boolean
Note that SHOW FIELD KEYS
handles field type discrepancies differently from
SELECT
statements.
For more information, see the
How does InfluxDB handle field type discrepancies across shards?.
SHOW CARDINALITY
SHOW CARDINALITY
refers to the group of commands used to estimate or count exactly
the cardinality of measurements, series, tag keys, tag key values, and field keys.
For more information on the SHOW CARDINALITY
commands,
see the InfluxQL reference entry.
SHOW FIELD KEY CARDINALITY
-- show estimated cardinality of the field key set of current database
SHOW FIELD KEY CARDINALITY
-- show exact cardinality on field key set of specified database
SHOW FIELD KEY EXACT CARDINALITY ON mydb
SHOW MEASUREMENT KEY CARDINALITY
-- show estimated cardinality of measurement set on current database
SHOW MEASUREMENT CARDINALITY
-- show exact cardinality of measurement set on specified database
SHOW MEASUREMENT EXACT CARDINALITY ON mydb
SHOW SERIES CARDINALITY
-- show estimated cardinality of the series on current database
SHOW SERIES CARDINALITY
-- show estimated cardinality of the series on specified database
SHOW SERIES CARDINALITY ON mydb
-- show exact series cardinality
SHOW SERIES EXACT CARDINALITY
-- show series cardinality of the series on specified database
SHOW SERIES EXACT CARDINALITY ON mydb
SHOW TAG KEY CARDINALITY
-- show estimated tag key cardinality
SHOW TAG KEY CARDINALITY
-- show exact tag key cardinality
SHOW TAG KEY EXACT CARDINALITY
SHOW TAG VALUES CARDINALITY
-- show estimated tag key values cardinality for a specified tag key
SHOW TAG VALUES CARDINALITY WITH KEY = "myTagKey"
-- show estimated tag key values cardinality for a specified tag key
SHOW TAG VALUES CARDINALITY WITH KEY = "myTagKey"
-- show exact tag key values cardinality for a specified tag key
SHOW TAG VALUES EXACT CARDINALITY WITH KEY = "myTagKey"
-- show exact tag key values cardinality for a specified tag key
SHOW TAG VALUES EXACT CARDINALITY WITH KEY = "myTagKey"
Filter meta queries by time
When you filter meta queries by time, you may see results outside of your specified time. Meta query results are filtered at the shard level, so results can be approximately as granular as your shard group duration. If your time filter spans multiple shards, you’ll get results from all shards with points in the specified time range. To review your shards and timestamps on points in the shard, run SHOW SHARDS
. To learn more about shards and their duration, see recommended shard groups durations.
The example below shows how to filter SHOW TAG KEYS
by approximately one hour using a 1h shard group duration. To filter other meta data, replace SHOW TAG KEYS
with SHOW TAG VALUES
, SHOW SERIES
, SHOW FIELD KEYS
, and so on.
Note:
SHOW MEASUREMENTS
cannot be filtered by time.
Example filtering SHOW TAG KEYS
by time
-
Specify a shard duration on a new database or alter an existing shard duration. To specify a 1h shard duration when creating a new database, run the following command:
> CREATE database mydb with duration 7d REPLICATION 1 SHARD DURATION 1h name myRP;
Note: The minimum shard duration is 1h.
-
Verify the shard duration has the correct time interval (precision) by running the
SHOW SHARDS
command. The example below shows a shard duration with an hour precision.> SHOW SHARDS name: mydb id database retention_policy shard_group start_time end_time expiry_time owners -- -------- ---------------- ----------- ---------- -------- ----------- ------ > precision h
-
(Optional) Insert sample tag keys. This step is for demonstration purposes. If you already have tag keys (or other meta data) to search for, skip this step.
// Insert a sample tag called "test_key" into the "test" measurement, and then check the timestamp: > INSERT test,test_key=hello value=1 > select * from test name: test time test_key value ---- -------- ----- 434820 hello 1 // Add new tag keys with timestamps one, two, and three hours earlier: > INSERT test,test_key_1=hello value=1 434819 > INSERT test,test_key_2=hello value=1 434819 > INSERT test,test_key_3_=hello value=1 434818 > INSERT test,test_key_4=hello value=1 434817 > INSERT test,test_key_5_=hello value=1 434817
-
To find tag keys within a shard duration, run one of the following commands:
SHOW TAG KEYS ON database-name <WHERE time clause>
ORSELECT * FROM measurement <WHERE time clause>
The examples below use test data from step 3.
//Using data from Step 3, show tag keys between now and an hour ago > SHOW TAG KEYS ON mydb where time > now() -1h and time < now() name: test tagKey ------ test_key test_key_1 test_key_2 // Find tag keys between one and two hours ago > SHOW TAG KEYS ON mydb where > time > now() -2h and time < now()-1h name: test tagKey ------ test_key_1 test_key_2 test_key_3 // Find tag keys between two and three hours ago > SHOW TAG KEYS ON mydb where > time > now() -3h and time < now()-2h name: test tagKey ------ test_key_3 test_key_4 test_key_5 // For a specified measurement, find tag keys in a given shard by specifying the time boundaries of the shard > SELECT * FROM test WHERE time >= '2019-08-09T00:00:00Z' and time < '2019-08-09T10:00:00Z' name: test time test_key_4 test_key_5 value ---- ------------ ------------ ----- 434817 hello 1 434817 hello 1 // For a specified database, find tag keys in a given shard by specifying the time boundaries of the shard > SHOW TAG KEYS ON mydb WHERE time >= '2019-08-09T00:00:00Z' and time < '2019-08-09T10:00:00Z' name: test tagKey ------ test_key_4 test_key_5
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Support and feedback
Thank you for being part of our community! We welcome and encourage your feedback and bug reports for InfluxDB and this documentation. To find support, use the following resources:
Customers with an annual or support contract can contact InfluxData Support.