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InfluxQL SHOW statements | Use InfluxQL `SHOW` statements to query schema information from a database. |
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207 | ```sql SHOW [MEASUREMENTS | FIELD KEYS | TAG KEYS | TAG VALUES] ``` |
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Use InfluxQL SHOW
statements to query schema information from a database.
SHOW MEASUREMENTS
Use the SHOW MEASUREMENTS
statement to list measurements in a database.
SHOW MEASUREMENTS [with_measurement_clause] [where_clause] [limit_clause] [offset_clause]
Examples
-- Show all measurements
SHOW MEASUREMENTS
-- Show measurements where region tag = 'uswest' AND host tag = 'serverA'
SHOW MEASUREMENTS WHERE "region" = 'uswest' AND "host" = 'serverA'
-- Show measurements that start with 'h2o'
SHOW MEASUREMENTS WITH MEASUREMENT =~ /h2o.*/
SHOW FIELD KEYS
Use the SHOW FIELD KEYS
statement to list all field keys in a measurement.
SHOW FIELD KEYS [from_clause]
Examples
-- Show field keys and field value data types from all measurements
SHOW FIELD KEYS
-- Show field keys and field value data types from specified measurement
SHOW FIELD KEYS FROM "cpu"
SHOW TAG KEYS
Use the SHOW TAG KEYS
statement to list tag keys in a measurement.
SHOW TAG KEYS [from_clause] [where_clause] [limit_clause] [offset_clause]
Examples
-- Show all tag keys
SHOW TAG KEYS
-- Show all tag keys from the cpu measurement
SHOW TAG KEYS FROM "cpu"
-- Show all tag keys from the cpu measurement where the region key = 'uswest'
SHOW TAG KEYS FROM "cpu" WHERE "region" = 'uswest'
-- Show all tag keys where the host key = 'serverA'
SHOW TAG KEYS WHERE "host" = 'serverA'
SHOW TAG VALUES
Use the SHOW TAG VALUES
statement to list values of specified tags in a database.
SHOW TAG VALUES [from_clause] WITH KEY = <tag-expression> [where_clause] [limit_clause] [offset_clause]
By default, the SHOW TAG VALUES
statement only returns unique tag values from
the last day. To modify the time range, include
WHERE
clause with a time-based predicate.
{{% note %}}
Include a FROM clause
We strongly recommend including a FROM
clause with the SHOW TAG VALUES
statement that specifies 1-50 tables to query.
Without a FROM
clause, the InfluxDB query engine must read data from all
tables and return unique tag values from each.
Depending on the number of tables in your database and the number of unique tag
values in each table, excluding a FROM
clause can result in poor query performance,
query timeouts, or unnecessary resource allocation that may affect other queries.
{{% /note %}}
Examples
-- Show tag values from the cpu measurement for the region tag
SHOW TAG VALUES FROM "cpu" WITH KEY = "region"
-- Show tag values from the cpu measurement for the region tag for a custom time range
SHOW TAG VALUES FROM "cpu" WITH KEY = "region" WHERE time > -7d
-- Show tag values from multiple measurements for the region tag
SHOW TAG VALUES FROM "cpu", "memory", "disk" WITH KEY = "region"
-- Show tag values from the cpu measurement for all tag keys that do not include the letter c
SHOW TAG VALUES FROM "cpu" WITH KEY !~ /.*c.*/
-- Show tag values from the cpu measurement for region & host tag keys where service = 'redis'
SHOW TAG VALUES FROM "cpu" WITH KEY IN ("region", "host") WHERE "service" = 'redis'