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Posted to commits@iotdb.apache.org by ro...@apache.org on 2021/09/22 10:01:32 UTC
[iotdb] branch nested-operations updated: add user doc for nested
queries
This is an automated email from the ASF dual-hosted git repository.
rong pushed a commit to branch nested-operations
in repository https://gitbox.apache.org/repos/asf/iotdb.git
The following commit(s) were added to refs/heads/nested-operations by this push:
new ebad755 add user doc for nested queries
ebad755 is described below
commit ebad755b267700f4d3ff052961fc022c01682aa6
Author: Steve Yurong Su <ro...@apache.org>
AuthorDate: Wed Sep 22 18:00:47 2021 +0800
add user doc for nested queries
---
.../DML-Data-Manipulation-Language.md | 67 ++++++++++++++++++++
.../DML-Data-Manipulation-Language.md | 71 +++++++++++++++++++++-
site/src/main/.vuepress/config.js | 4 +-
3 files changed, 138 insertions(+), 4 deletions(-)
diff --git a/docs/UserGuide/IoTDB-SQL-Language/DML-Data-Manipulation-Language.md b/docs/UserGuide/IoTDB-SQL-Language/DML-Data-Manipulation-Language.md
index 17ac0b8..76e1bc9 100644
--- a/docs/UserGuide/IoTDB-SQL-Language/DML-Data-Manipulation-Language.md
+++ b/docs/UserGuide/IoTDB-SQL-Language/DML-Data-Manipulation-Language.md
@@ -427,6 +427,73 @@ It costs 0.014s
Please refer to [UDF (User Defined Function)](../Advanced-Features/UDF-User-Defined-Function.md).
+Known Implementation UDF Libraries:
+
++ [IoTDB-Quality](https://thulab.github.io/iotdb-quality), a UDF library about data quality, including data profiling, data quality evalution and data repairing, etc.
+
+### Nested Query (Subquery)
+
+"Nested query" is also called "subquery", that is, in a SQL statement, the result of the "inner query" can be used as the input of the "outer query".
+
+IoTDB supports the execution of arbitrary nested expressions consisting of **time series, arithmetic expressions, and time series generation functions (including user-defined functions)** in the `select` clause.
+
+#### Syntax
+
+The following is the syntax definition of the `select` clause:
+
+```sql
+selectClause
+ : SELECT resultColumn (',' resultColumn)*
+ ;
+
+resultColumn
+ : expression (AS ID)?
+ ;
+
+expression
+ : '(' expression ')'
+ | '-' expression
+ | expression ('*' | '/' | '%') expression
+ | expression ('+' | '-') expression
+ | functionName '(' expression (',' expression)* functionAttribute* ')'
+ | timeSeriesSuffixPath
+ ;
+```
+
+#### Example
+
+SQL:
+
+```sql
+select
+ a,
+ b,
+ sin(a + sin(a + sin(b))),
+ -(a + b) * (sin(a + b) * sin(a + b) + cos(a + b) * cos(a + b))
+from root.sg1.d1;
+```
+
+Result:
+
+```
++-----------------------------+-------------+-------------+------------------------------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
+| Time|root.sg1.d1.a|root.sg1.d1.b|sin(root.sg1.d1.a + sin(root.sg1.d1.a + sin(root.sg1.d1.b)))|-root.sg1.d1.a + root.sg1.d1.b * sin(root.sg1.d1.a + root.sg1.d1.b) * sin(root.sg1.d1.a + root.sg1.d1.b) + cos(root.sg1.d1.a + root.sg1.d1.b) * cos(root.sg1.d1.a + root.sg1.d1.b)|
++-----------------------------+-------------+-------------+------------------------------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
+|1970-01-01T08:00:00.000+08:00| 0| 0| 0.0| -0.0|
+|1970-01-01T08:00:00.001+08:00| 1| 1| 0.9238430524420609| -2.0|
+|1970-01-01T08:00:00.002+08:00| 2| 2| 0.7903505371876317| -4.0|
+|1970-01-01T08:00:00.003+08:00| 3| 3| 0.14065207680386618| -5.999999999999999|
+|1970-01-01T08:00:00.004+08:00| 4| 4| -0.6867272852305377| -8.0|
+|1970-01-01T08:00:00.005+08:00| 5| 5| -0.8797812615294988| -10.0|
+|1970-01-01T08:00:00.006+08:00| 6| 6| -0.7288037411970917| -12.0|
+|1970-01-01T08:00:00.007+08:00| 7| 7| 0.9919871278709939| -14.0|
+|1970-01-01T08:00:00.008+08:00| 8| 8| 0.8430810955779515| -16.0|
+|1970-01-01T08:00:00.009+08:00| 9| 9| 0.4005516488102476| -18.0|
++-----------------------------+-------------+-------------+------------------------------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
+Total line number = 10
+It costs 0.029s
+```
+
### Aggregate Query
This section mainly introduces the related examples of aggregate query.
diff --git a/docs/zh/UserGuide/IoTDB-SQL-Language/DML-Data-Manipulation-Language.md b/docs/zh/UserGuide/IoTDB-SQL-Language/DML-Data-Manipulation-Language.md
index fdd21dc..4795de2 100644
--- a/docs/zh/UserGuide/IoTDB-SQL-Language/DML-Data-Manipulation-Language.md
+++ b/docs/zh/UserGuide/IoTDB-SQL-Language/DML-Data-Manipulation-Language.md
@@ -432,11 +432,78 @@ Total line number = 5
It costs 0.014s
```
-#### 自定义序列生成函数
+#### 自定义时间序列生成函数
请参考 [UDF （用户定义函数）](../Advanced-Features/UDF-User-Defined-Function.md)。
-### 聚合函数
+已知的自定义时间序列生成函数库实现：
+
++ [IoTDB-Quality](https://thulab.github.io/iotdb-quality)，一个关于数据质量的 UDF 库实现，包括数据画像、数据质量评估与修复等一系列函数。
+
+### 嵌套查询（子查询）
+
+“嵌套查询”又称为“子查询，即在一条 SQL 语句中，“内层查询”的计算结果可以作为“外层查询”的计算对象来使用。
+
+IoTDB 支持在 `select` 字句中执行由**时间序列、算数运算表达式和时间序列生成函数（包括用户自定义函数）**组成的任意嵌套表达式。
+
+#### 语法
+
+下面是 `select` 子句的语法定义：
+
+```sql
+selectClause
+ : SELECT resultColumn (',' resultColumn)*
+ ;
+
+resultColumn
+ : expression (AS ID)?
+ ;
+
+expression
+ : '(' expression ')'
+ | '-' expression
+ | expression ('*' | '/' | '%') expression
+ | expression ('+' | '-') expression
+ | functionName '(' expression (',' expression)* functionAttribute* ')'
+ | timeSeriesSuffixPath
+ ;
+```
+
+#### 示例
+
+输入：
+
+```sql
+select
+ a,
+ b,
+ sin(a + sin(a + sin(b))),
+ -(a + b) * (sin(a + b) * sin(a + b) + cos(a + b) * cos(a + b))
+from root.sg1.d1;
+```
+
+结果：
+
+```
++-----------------------------+-------------+-------------+------------------------------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
+| Time|root.sg1.d1.a|root.sg1.d1.b|sin(root.sg1.d1.a + sin(root.sg1.d1.a + sin(root.sg1.d1.b)))|-root.sg1.d1.a + root.sg1.d1.b * sin(root.sg1.d1.a + root.sg1.d1.b) * sin(root.sg1.d1.a + root.sg1.d1.b) + cos(root.sg1.d1.a + root.sg1.d1.b) * cos(root.sg1.d1.a + root.sg1.d1.b)|
++-----------------------------+-------------+-------------+------------------------------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
+|1970-01-01T08:00:00.000+08:00| 0| 0| 0.0| -0.0|
+|1970-01-01T08:00:00.001+08:00| 1| 1| 0.9238430524420609| -2.0|
+|1970-01-01T08:00:00.002+08:00| 2| 2| 0.7903505371876317| -4.0|
+|1970-01-01T08:00:00.003+08:00| 3| 3| 0.14065207680386618| -5.999999999999999|
+|1970-01-01T08:00:00.004+08:00| 4| 4| -0.6867272852305377| -8.0|
+|1970-01-01T08:00:00.005+08:00| 5| 5| -0.8797812615294988| -10.0|
+|1970-01-01T08:00:00.006+08:00| 6| 6| -0.7288037411970917| -12.0|
+|1970-01-01T08:00:00.007+08:00| 7| 7| 0.9919871278709939| -14.0|
+|1970-01-01T08:00:00.008+08:00| 8| 8| 0.8430810955779515| -16.0|
+|1970-01-01T08:00:00.009+08:00| 9| 9| 0.4005516488102476| -18.0|
++-----------------------------+-------------+-------------+------------------------------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
+Total line number = 10
+It costs 0.029s
+```
+
+### 聚合查询
本章节主要介绍聚合查询的相关示例，
主要使用的是 IoTDB SELECT 语句的聚合查询函数。
diff --git a/site/src/main/.vuepress/config.js b/site/src/main/.vuepress/config.js
index 4e478da..619c26e 100644
--- a/site/src/main/.vuepress/config.js
+++ b/site/src/main/.vuepress/config.js
@@ -688,7 +688,7 @@ var config = {
},
{
title: 'IoTDB-SQL Language',
- sidebarDepth: 1,
+ sidebarDepth: 2,
children: [
['IoTDB-SQL-Language/DDL-Data-Definition-Language','DDL (Data Definition Language)'],
['IoTDB-SQL-Language/DML-Data-Manipulation-Language','DML (Data Manipulation Language)'],
@@ -1484,7 +1484,7 @@ var config = {
},
{
title: 'IoTDB-SQL 语言',
- sidebarDepth: 1,
+ sidebarDepth: 2,
children: [
['IoTDB-SQL-Language/DDL-Data-Definition-Language','数据定义语言（DDL）'],
['IoTDB-SQL-Language/DML-Data-Manipulation-Language','数据操作语言（DML）'],