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Posted to commits@iotdb.apache.org by li...@apache.org on 2021/01/19 06:13:23 UTC
[iotdb] branch master updated: edit DDL, DML,
SQL doc for show devices limit (#2519)
This is an automated email from the ASF dual-hosted git repository.
liudw pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/iotdb.git
The following commit(s) were added to refs/heads/master by this push:
new 36e80ad edit DDL, DML, SQL doc for show devices limit (#2519)
36e80ad is described below
commit 36e80adc404c8ef23b0ca5235e64894214283fe4
Author: Haimei Guo <68...@users.noreply.github.com>
AuthorDate: Tue Jan 19 14:13:06 2021 +0800
edit DDL, DML, SQL doc for show devices limit (#2519)
---
.../DDL Data Definition Language.md | 2 ++
.../DML Data Manipulation Language.md | 37 +------------------
.../DDL Data Definition Language.md | 2 ++
.../DML Data Manipulation Language.md | 42 ----------------------
.../zh/UserGuide/Operation Manual/SQL Reference.md | 6 ++--
5 files changed, 8 insertions(+), 81 deletions(-)
diff --git a/docs/UserGuide/Operation Manual/DDL Data Definition Language.md b/docs/UserGuide/Operation Manual/DDL Data Definition Language.md
index 750363b..735820b 100644
--- a/docs/UserGuide/Operation Manual/DDL Data Definition Language.md
+++ b/docs/UserGuide/Operation Manual/DDL Data Definition Language.md
@@ -392,6 +392,8 @@ IoTDB> delete timeseries root.ln.wf02.*
## Show Devices
+* SHOW DEVICES prefixPath? limitClause?
+
Similar to `Show Timeseries`, IoTDB also supports two ways of viewing devices:
* `SHOW DEVICES` statement presents all devices information, which is equal to `SHOW DEVICES root`.
diff --git a/docs/UserGuide/Operation Manual/DML Data Manipulation Language.md b/docs/UserGuide/Operation Manual/DML Data Manipulation Language.md
index 0ce9898..dc25eea 100644
--- a/docs/UserGuide/Operation Manual/DML Data Manipulation Language.md
+++ b/docs/UserGuide/Operation Manual/DML Data Manipulation Language.md
@@ -541,41 +541,6 @@ Total line number = 7
It costs 0.006s
```
-#### Down-Frequency Aggregate Query Specifying the value Filtering Conditions
-
-The SQL statement is:
-
-```
-select count(status), max_value(temperature) from root.ln.wf01.wt01 where group by([2017-11-01T00:00:00, 2017-11-07T23:00:00), 3h, 1d);
-```
-which means:
-
-Since the user specifies the sliding step parameter as 1d, the GROUP BY statement will move the time interval `1 day` long instead of `3 hours` as default.
-
-The first parameter of the GROUP BY statement above is the display window parameter, which determines the final display range is [2017-11-01T00:00:00, 2017-11-07T23:00:00).
-
-The second parameter of the GROUP BY statement above is the time interval for dividing the time axis. Taking this parameter (3h) as time interval and the startTime of the display window as the dividing origin, the time axis is divided into several continuous intervals, which are [2017-11-01T00:00:00, 2017-11-01T03:00:00), [2017-11-02T00:00:00, 2017-11-02T03:00:00), [2017-11-03T00:00:00, 2017-11-03T03:00:00), etc.
-
-The third parameter of the GROUP BY statement above is the sliding step for each time interval moving.
-
-Then the system will use the time and value filtering condition in the WHERE clause and the first parameter of the GROUP BY statement as the data filtering condition to obtain the data satisfying the filtering condition (which in this case is the data in the range of (2017-11-01T00:00:00, 2017-11-07T23:00:00]), and map these data to the previously segmented time axis (in this case there are mapped data in every 3-hour period for each day from 2017-11-01T00:00:00 to 2017-11-07T23:00:00).
-
-```
-+-----------------------------+-------------------------------+----------------------------------------+
-| Time|count(root.ln.wf01.wt01.status)|max_value(root.ln.wf01.wt01.temperature)|
-+-----------------------------+-------------------------------+----------------------------------------+
-|2017-11-01T00:00:00.000+08:00| 180| 25.98|
-|2017-11-02T00:00:00.000+08:00| 179| 25.98|
-|2017-11-03T00:00:00.000+08:00| 180| 25.96|
-|2017-11-04T00:00:00.000+08:00| 180| 25.96|
-|2017-11-05T00:00:00.000+08:00| 180| 26.0|
-|2017-11-06T00:00:00.000+08:00| 180| 25.85|
-|2017-11-07T00:00:00.000+08:00| 180| 25.99|
-+-----------------------------+-------------------------------+----------------------------------------+
-Total line number = 7
-It costs 0.018s
-```
-
#### Down-Frequency Aggregate Query by Natural Month
The SQL statement is:
@@ -620,7 +585,7 @@ The SQL execution result is:
+-----------------------------+-------------------------------+
```
-对应的SQL语句是:
+The SQL statement is:
```
select count(status) from root.ln.wf01.wt01 group by([2017-10-31T00:00:00, 2019-11-07T23:00:00), 1mo, 2mo);
diff --git a/docs/zh/UserGuide/Operation Manual/DDL Data Definition Language.md b/docs/zh/UserGuide/Operation Manual/DDL Data Definition Language.md
index bd7b185..dee003d 100644
--- a/docs/zh/UserGuide/Operation Manual/DDL Data Definition Language.md
+++ b/docs/zh/UserGuide/Operation Manual/DDL Data Definition Language.md
@@ -366,6 +366,8 @@ IoTDB> delete timeseries root.ln.wf02.*
## 查看设备
+* SHOW DEVICES prefixPath? limitClause?
+
与 `Show Timeseries` 相似，IoTDB 目前也支持两种方式查看设备。
* `SHOW DEVICES` 语句显示当前所有的设备信息，等价于 `SHOW DEVICES root`。
* `SHOW DEVICES <PrefixPath>` 语句规定了 `PrefixPath`，返回在给定的前缀路径下的设备信息。
diff --git a/docs/zh/UserGuide/Operation Manual/DML Data Manipulation Language.md b/docs/zh/UserGuide/Operation Manual/DML Data Manipulation Language.md
index a7502d3..db951ff 100644
--- a/docs/zh/UserGuide/Operation Manual/DML Data Manipulation Language.md
+++ b/docs/zh/UserGuide/Operation Manual/DML Data Manipulation Language.md
@@ -597,46 +597,6 @@ Total line number = 7
It costs 0.006s
```
-#### 带值过滤条件的降频聚合查询
-
-对应的SQL语句是:
-
-```
-select count(status), max_value(temperature) from root.ln.wf01.wt01 group by([2017-11-01T00:00:00, 2017-11-07T23:00:00), 3h, 1d);
-```
-
-这条查询的含义是:
-
-由于用户指定了滑动步长为`1d`，GROUP BY语句执行时将会每次把时间间隔往后移动一天的步长，而不是默认的3小时。
-
-也就意味着，我们想要取从2017-11-01到2017-11-07每一天的凌晨0点到凌晨3点的数据。
-
-上面这个例子的第一个参数是显示窗口参数，决定了最终的显示范围是[2017-11-01T00:00:00, 2017-11-07T23:00:00)。
-
-上面这个例子的第二个参数是划分时间轴的时间间隔参数，将`3h`当作划分间隔，显示窗口参数的起始时间当作分割原点，时间轴即被划分为连续的时间间隔：[2017-11-01T00:00:00, 2017-11-01T03:00:00), [2017-11-02T00:00:00, 2017-11-02T03:00:00), [2017-11-03T00:00:00, 2017-11-03T03:00:00)等等。
-
-上面这个例子的第三个参数是每次时间间隔的滑动步长。
-
-然后系统将会用WHERE子句中的时间和值过滤条件以及GROUP BY语句中的第一个参数作为数据的联合过滤条件，获得满足所有过滤条件的数据（在这个例子里是在[2017-11-01T00:00:00, 2017-11-07 T23:00:00)这个时间范围的数据），并把这些数据映射到之前分割好的时间轴中（这个例子里是从2017-11-01T00:00:00到2017-11-07T23:00:00:00的每一天的凌晨0点到凌晨3点）
-
-每个时间间隔窗口内都有数据，SQL执行后的结果集如下所示：
-
-```
-+-----------------------------+-------------------------------+----------------------------------------+
-| Time|count(root.ln.wf01.wt01.status)|max_value(root.ln.wf01.wt01.temperature)|
-+-----------------------------+-------------------------------+----------------------------------------+
-|2017-11-01T00:00:00.000+08:00| 180| 25.98|
-|2017-11-02T00:00:00.000+08:00| 179| 25.98|
-|2017-11-03T00:00:00.000+08:00| 180| 25.96|
-|2017-11-04T00:00:00.000+08:00| 180| 25.96|
-|2017-11-05T00:00:00.000+08:00| 180| 26.0|
-|2017-11-06T00:00:00.000+08:00| 180| 25.85|
-|2017-11-07T00:00:00.000+08:00| 180| 25.99|
-+-----------------------------+-------------------------------+----------------------------------------+
-Total line number = 7
-It costs 0.018s
-```
-
#### 按照自然月份的降频聚合查询
对应的SQL语句是:
@@ -693,8 +653,6 @@ select count(status) from root.ln.wf01.wt01 group by([2017-10-31T00:00:00, 2019-
由于用户指定了滑动步长为`2mo`，GROUP BY语句执行时将会每次把时间间隔往后移动2个自然月的步长，而不是默认的1个自然月。
-由于用户指定了滑动步长为`2mo`，GROUP BY语句执行时将会每次把时间间隔往后移动2个自然月的步长，而不是默认的1个自然月。
-
也就意味着，我们想要取从2017-10-31到2029-11-07每2个自然月的第一个月的数据。
与上述示例不同的是起始时间为2017-10-31T00:00:00，滑动步长将会以起始时间作为标准按月递增，取当月的31号（即最后一天）作为时间间隔的起始时间。若起始时间设置为30号，滑动步长会将时间间隔的起始时间设置为当月30号，若不存在则为最后一天。
diff --git a/docs/zh/UserGuide/Operation Manual/SQL Reference.md b/docs/zh/UserGuide/Operation Manual/SQL Reference.md
index d2ac269..1af6f60 100644
--- a/docs/zh/UserGuide/Operation Manual/SQL Reference.md
+++ b/docs/zh/UserGuide/Operation Manual/SQL Reference.md
@@ -245,15 +245,15 @@ Note: This statement can be used in IoTDB Client and JDBC.
* 显示所有设备语句
```
-SHOW DEVICES
-Eg: IoTDB > SHOW DEVICES
+SHOW DEVICES limitClause?
+Eg: IoTDB > SHOW DEVICES
Note: This statement can be used in IoTDB Client and JDBC.
```
* 显示特定设备语句
```
-SHOW DEVICES <PrefixPath>
+SHOW DEVICES <PrefixPath> limitClause?
Eg: IoTDB > SHOW DEVICES root
Eg: IoTDB > SHOW DEVICES root.ln
Eg: IoTDB > SHOW DEVICES root.*.wf01