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docs: grammar: sql functions 

Minor grammar and formatting updates to SQL > Functions page
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Sean Ely 2022-05-25 13:20:15 -07:00 committed by gccgdb1234
parent f7811dd3cf
commit cc820359c4
1 changed files with 51 additions and 51 deletions
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docs-en/12-taos-sql/07-function.md
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@ -4,7 +4,7 @@ title: Functions
## Aggregate Functions ## Aggregate Functions
Aggregate query is supported in TDengine by following aggregate functions and selection functions. Aggregate queries are supported in TDengine by the following aggregate functions and selection functions.
### COUNT ### COUNT
@ -261,7 +261,7 @@ Query OK, 1 row(s) in set (0.008388s)
## Selection Functions ## Selection Functions
When any selective function is used, timestamp column or tag columns including `tbname` can be specified to show that the selected value are from which rows. When any select function is used, timestamp column or tag columns including `tbname` can be specified to show that the selected value are from which rows.
### MIN ### MIN
@ -584,7 +584,7 @@ SELECT INTERP(field_name) FROM { tb_name | stb_name } [WHERE where_condition] [
**Description**: The value that matches the specified timestamp range is returned, if existing; or an interpolation value is returned. **Description**: The value that matches the specified timestamp range is returned, if existing; or an interpolation value is returned.
**Return value type**: same as the column being operated **Return value type**: Same as the column being operated
**Applicable column types**: Numeric data types **Applicable column types**: Numeric data types
@ -608,7 +608,7 @@ SELECT INTERP(field_name) FROM { tb_name | stb_name } [WHERE where_condition] [
taos> SELECT INTERP(current) FROM t1 RANGE('2017-7-14 18:40:00','2017-7-14 18:40:00') FILL(LINEAR); taos> SELECT INTERP(current) FROM t1 RANGE('2017-7-14 18:40:00','2017-7-14 18:40:00') FILL(LINEAR);
``` ```
- Get an original data every 5 seconds, no interpolation, between "2017-07-14 18:00:00" and "2017-07-14 19:00:00: - Get original data every 5 seconds, no interpolation, between "2017-07-14 18:00:00" and "2017-07-14 19:00:00:
``` ```
taos> SELECT INTERP(current) FROM t1 RANGE('2017-7-14 18:00:00','2017-7-14 19:00:00') EVERY(5s); taos> SELECT INTERP(current) FROM t1 RANGE('2017-7-14 18:00:00','2017-7-14 19:00:00') EVERY(5s);
@ -662,7 +662,7 @@ SELECT INTERP(field_name) FROM { tb_name | stb_name } WHERE ts='timestamp' [FILL
Query OK, 1 row(s) in set (0.002652s) Query OK, 1 row(s) in set (0.002652s)
``` ```
If there is not any data corresponding to the specified timestamp, an interpolation value is returned if interpolation policy is specified by `FILL` parameter; or nothing is returned\ If there is no data corresponding to the specified timestamp, an interpolation value is returned if interpolation policy is specified by `FILL` parameter; or nothing is returned.
``` ```
taos> SELECT INTERP(*) FROM meters WHERE tbname IN ('d636') AND ts='2017-7-14 18:40:00.005'; taos> SELECT INTERP(*) FROM meters WHERE tbname IN ('d636') AND ts='2017-7-14 18:40:00.005';
@ -819,7 +819,7 @@ SELECT DERIVATIVE(field_name, time_interval, ignore_negative) FROM tb_name [WHER
**More explanations**: **More explanations**:
- It is available from version 2.1.3.0, the number of result rows is the number of total rows in the time range subtracted by one, no output for the first row.\ - It is available from version 2.1.3.0, the number of result rows is the number of total rows in the time range subtracted by one, no output for the first row.
- It can be used together with `GROUP BY tbname` against a STable. - It can be used together with `GROUP BY tbname` against a STable.
**Examples**: **Examples**:
@ -882,7 +882,7 @@ SELECT CEIL(field_name) FROM { tb_name | stb_name } [WHERE clause];
**Applicable table types**: table, STable **Applicable table types**: table, STable
**Applicable nested query**: inner query and outer query **Applicable nested query**: Inner query and outer query
**More explanations**: **More explanations**: