From 1e46bb51d2f831d80591ead4a858d679382accd3 Mon Sep 17 00:00:00 2001 From: root Date: Tue, 28 Jul 2020 09:28:50 +0800 Subject: [PATCH] fix some doc errors on website --- documentation/webdocs/markdowndocs/TAOS SQL-ch.md | 4 ++-- documentation/webdocs/markdowndocs/TAOS SQL.md | 15 ++++++++++++--- 2 files changed, 14 insertions(+), 5 deletions(-) diff --git a/documentation/webdocs/markdowndocs/TAOS SQL-ch.md b/documentation/webdocs/markdowndocs/TAOS SQL-ch.md index 343ce80422..e494a1be45 100644 --- a/documentation/webdocs/markdowndocs/TAOS SQL-ch.md +++ b/documentation/webdocs/markdowndocs/TAOS SQL-ch.md @@ -556,7 +556,7 @@ TDengine支持针对数据的聚合查询。提供支持的聚合和选择函数 功能说明：统计表中某列的值百分比分位数。 返回结果数据类型： 双精度浮点数Double。 应用字段：不能应用在timestamp、binary、nchar、bool类型字段。 - 说明：*k*值取值范围0≤*k*≤100，为0的时候等同于MIN，为100的时候等同于MAX。 + 说明：*k*值取值范围0≤*P*≤100，为0的时候等同于MIN，为100的时候等同于MAX。 - **APERCENTILE** ```mysql @@ -565,7 +565,7 @@ TDengine支持针对数据的聚合查询。提供支持的聚合和选择函数 功能说明：统计表中某列的值百分比分位数，与PERCENTILE函数相似，但是返回近似结果。 返回结果数据类型： 双精度浮点数Double。 应用字段：不能应用在timestamp、binary、nchar、bool类型字段。 - 说明：*k*值取值范围0≤*k*≤100，为0的时候等同于MIN，为100的时候等同于MAX。推荐使用```APERCENTILE```函数，该函数性能远胜于```PERCENTILE```函数 + 说明：*k*值取值范围0≤*P*≤100，为0的时候等同于MIN，为100的时候等同于MAX。推荐使用```APERCENTILE```函数，该函数性能远胜于```PERCENTILE```函数 - **LAST_ROW** ```mysql diff --git a/documentation/webdocs/markdowndocs/TAOS SQL.md b/documentation/webdocs/markdowndocs/TAOS SQL.md index c0d35e9afc..f94047fb6a 100644 --- a/documentation/webdocs/markdowndocs/TAOS SQL.md +++ b/documentation/webdocs/markdowndocs/TAOS SQL.md @@ -289,10 +289,10 @@ TDengine supports aggregations over numerical values, they are listed below: Applied to: table/STable. -- **WAVG** +- **TWA** ```mysql - SELECT WAVG(field_name) FROM tb_name WHERE clause + SELECT TWA(field_name) FROM tb_name WHERE clause ``` Function: return the time-weighted average value of a specific column Return Data Type: `double` @@ -324,7 +324,7 @@ TDengine supports aggregations over numerical values, they are listed below: - **LEASTSQUARES** ```mysql - SELECT LEASTSQUARES(field_name) FROM tb_name [WHERE clause] + SELECT LEASTSQUARES(field_name, start_val, step_val) FROM tb_name [WHERE clause] ``` Function: performs a linear fit to the primary timestamp and the specified column. Return Data Type: return a string of the coefficient and the interception of the fitted line. @@ -417,6 +417,15 @@ TDengine supports aggregations over numerical values, they are listed below: Applied to: table/STable. Note: The range of `P` is `[0, 100]`. When `P=0` , `PERCENTILE` returns the equal value as `MIN`; when `P=100`, `PERCENTILE` returns the equal value as `MAX`. +- **APERCENTILE** + ```mysql + SELECT APERCENTILE(field_name, P) FROM { tb_name | stb_name } [WHERE clause] + ``` + Function: the value of the specified column below which `P` percent of the data points fall, it returns approximate value of percentile. + Return Data Type: double. + Applicable Data Types: all types except `timestamp`, `binary`, `nchar`, `bool`. + Applied to: table/STable. + Note: The range of `P` is `[0, 100]`. When `P=0` , `APERCENTILE` returns the equal value as `MIN`; when `P=100`, `APERCENTILE` returns the equal value as `MAX`. `APERCENTILE` has a much better performance than `PERCENTILE`. - **LAST_ROW** ```mysql -- GitLab