Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Add example results for User Guide documents #2171

Merged
merged 9 commits into from
Dec 7, 2020
+1,394 −292
Merged

Add example results for User Guide documents #2171

Show file tree
Hide file tree
Changes from 3 commits
Commits
Show all changes
9 commits
Select commit Hold shift + click to select a range
2750f2e
update doc
Genius-pig Dec 3, 2020
571aca5
remove photo
Genius-pig Dec 3, 2020
90f3876
update doc
Genius-pig Dec 3, 2020
2649c77
Revert "update doc"
Genius-pig Dec 4, 2020
0e7b869
remove some photo
Genius-pig Dec 4, 2020
98d8fc6
update doc
Genius-pig Dec 4, 2020
02aa397
update cn doc
Genius-pig Dec 4, 2020
693551d
update cn
Genius-pig Dec 4, 2020
53fa435
Update DDL Data Definition Language.md
jixuan1989 Dec 5, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
179 changes: 158 additions & 21 deletions docs/UserGuide/Operation Manual/DDL Data Definition Language.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -32,7 +32,7 @@ IoTDB > set storage group to root.sgcc

We can thus create two storage groups using the above two SQL statements.

It is worth noting that when the path itself or the parent/child layer of the path is already set as a storage group, the path is then not allowed to be set as a storage group. For example, it is not feasible to set `root.ln.wf01` as a storage group when two storage groups `root.ln` and `root.sgcc` exist. The system gives the corresponding error prompt as shown below:
It is worth noting that when the path itself, or the parent/child layer of the path is already set as a storage group, the path is then not allowed to be set as a storage group. For example, it is not feasible to set `root.ln.wf01` as a storage group when two storage groups `root.ln` and `root.sgcc` exist. The system gives the corresponding error prompt as shown below:
jixuan1989 marked this conversation as resolved.
Show resolved Hide resolved

```
IoTDB> set storage group to root.ln.wf01
Expand All @@ -41,15 +41,25 @@ Msg: org.apache.iotdb.exception.MetadataException: org.apache.iotdb.exception.Me

## Show Storage Group

After the storage group is created, we can use the [SHOW STORAGE GROUP](../Operation%20Manual/SQL%20Reference.md) statement and [SHOW STORAGE GROUP \<PrefixPath>](../Operation%20Manual/SQL%20Reference.md) to view the storage groups. The SQL statements are as follows:
After creating the storage group, we can use the [SHOW STORAGE GROUP](../Operation%20Manual/SQL%20Reference.md) statement and [SHOW STORAGE GROUP \<PrefixPath>](../Operation%20Manual/SQL%20Reference.md) to view the storage groups. The SQL statements are as follows:

```
IoTDB> show storage group
IoTDB> show storage group root.ln
```

The result is as follows:
<center><img style="width:100%; max-width:800px; max-height:600px; margin-left:auto; margin-right:auto; display:block;" src="https://user-images.githubusercontent.com/67779101/92545299-6c029400-f282-11ea-80ea-b672a57f4b13.png"></center>

```
+-------------+
|storage group|
+-------------+
| root.sgcc|
| root.ln|
+-------------+
Total line number = 2
It costs 0.060s
```
Comment on lines +52 to +62
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Add result of show storage group root.ln like previous graph?


## Delete Storage Group

Expand Down Expand Up @@ -111,7 +121,7 @@ ALTER timeseries root.turbine.d1.s1 RENAME tag1 TO newTag1
```
* reset the tag/attribute value
```
ALTER timeseries root.turbine.d1.s1 SET tag1=newV1, attr1=newV1
ALTER timeseries root.turbine.d1.s1 SET newTag1=newV1, attr1=newV1
```
* delete the existing tag/attribute
```
Expand Down Expand Up @@ -156,20 +166,63 @@ IoTDB> show timeseries root.ln

The results are shown below respectively:

<center><img style="width:100%; max-width:800px; max-height:600px; margin-left:auto; margin-right:auto; display:block;" src="https://user-images.githubusercontent.com/13203019/51577347-8db7d780-1ef4-11e9-91d6-764e58c10e94.jpg"></center>
<center><img style="width:100%; max-width:800px; max-height:600px; margin-left:auto; margin-right:auto; display:block;" src="https://user-images.githubusercontent.com/13203019/51577359-97413f80-1ef4-11e9-8c10-53b291fc10a5.jpg"></center>
```
+-------------------------------+--------+-------------+--------+--------+-----------+-------------------------------------------+--------------------------------------------------------+
| timeseries| alias|storage group|dataType|encoding|compression| tags| attributes|
+-------------------------------+--------+-------------+--------+--------+-----------+-------------------------------------------+--------------------------------------------------------+
|root.sgcc.wf03.wt01.temperature| null| root.sgcc| FLOAT| RLE| SNAPPY| null| null|
| root.sgcc.wf03.wt01.status| null| root.sgcc| BOOLEAN| PLAIN| SNAPPY| null| null|
| root.turbine.d1.s1|newAlias| root.turbine| FLOAT| RLE| SNAPPY|{"newTag1":"newV1","tag4":"v4","tag3":"v3"}|{"attr2":"v2","attr1":"newV1","attr4":"v4","attr3":"v3"}|
| root.ln.wf02.wt02.hardware| null| root.ln| TEXT| PLAIN| SNAPPY| null| null|
| root.ln.wf02.wt02.status| null| root.ln| BOOLEAN| PLAIN| SNAPPY| null| null|
| root.ln.wf01.wt01.temperature| null| root.ln| FLOAT| RLE| SNAPPY| null| null|
| root.ln.wf01.wt01.status| null| root.ln| BOOLEAN| PLAIN| SNAPPY| null| null|
+-------------------------------+--------+-------------+--------+--------+-----------+-------------------------------------------+--------------------------------------------------------+
Total line number = 7
It costs 0.016s

+-----------------------------+-----+-------------+--------+--------+-----------+----+----------+
| timeseries|alias|storage group|dataType|encoding|compression|tags|attributes|
+-----------------------------+-----+-------------+--------+--------+-----------+----+----------+
| root.ln.wf02.wt02.hardware| null| root.ln| TEXT| PLAIN| SNAPPY|null| null|
| root.ln.wf02.wt02.status| null| root.ln| BOOLEAN| PLAIN| SNAPPY|null| null|
|root.ln.wf01.wt01.temperature| null| root.ln| FLOAT| RLE| SNAPPY|null| null|
| root.ln.wf01.wt01.status| null| root.ln| BOOLEAN| PLAIN| SNAPPY|null| null|
+-----------------------------+-----+-------------+--------+--------+-----------+----+----------+
Total line number = 4
It costs 0.004s
```

* SHOW TIMESERIES (<`PrefixPath`>)? WhereClause

returns all the timeseries information that satisfy the where condition and start with the prefixPath SQL statements are as follows:

```
ALTER timeseries root.ln.wf02.wt02.hardware ADD TAGS unit=c
ALTER timeseries root.ln.wf02.wt02.status ADD TAGS description=test1
show timeseries root.ln where unit=c
show timeseries root.ln where description contains 'test1'
```

The results are shown below respectly:
<center><img style="width:100%; max-width:800px; max-height:600px; margin-left:auto; margin-right:auto; display:block;" src="https://user-images.githubusercontent.com/16079446/79682385-61544d80-8254-11ea-8c23-9e93e7152fda.png"></center>

```
+--------------------------+-----+-------------+--------+--------+-----------+------------+----------+
| timeseries|alias|storage group|dataType|encoding|compression| tags|attributes|
+--------------------------+-----+-------------+--------+--------+-----------+------------+----------+
|root.ln.wf02.wt02.hardware| null| root.ln| TEXT| PLAIN| SNAPPY|{"unit":"c"}| null|
+--------------------------+-----+-------------+--------+--------+-----------+------------+----------+
Total line number = 1
It costs 0.005s

+------------------------+-----+-------------+--------+--------+-----------+-----------------------+----------+
| timeseries|alias|storage group|dataType|encoding|compression| tags|attributes|
+------------------------+-----+-------------+--------+--------+-----------+-----------------------+----------+
|root.ln.wf02.wt02.status| null| root.ln| BOOLEAN| PLAIN| SNAPPY|{"description":"test1"}| null|
+------------------------+-----+-------------+--------+--------+-----------+-----------------------+----------+
Total line number = 1
It costs 0.004s
```

> Notice that, we only support one condition in the where clause. Either it's an equal filter or it is an `contains` filter. In both case, the property in the where condition must be a tag.

Expand Down Expand Up @@ -202,18 +255,11 @@ Example：
|root.ln.wf01|
|root.ln.wf02|
+------------+
Total line number = 2
It costs 0.002s
```

* get all paths in form of root.xx.xx.xx：show child paths root.\*.\*

```
+---------------+
| child paths|
+---------------+
|root.ln.wf01.s1|
|root.ln.wf02.s2|
+---------------+
```
> get all paths in form of root.xx.xx.xx：show child paths root.xx.xx

## Count Timeseries

Expand All @@ -229,9 +275,25 @@ IoTDB > COUNT TIMESERIES root.ln.wf01.wt01.status
Besides, `LEVEL` could be defined to show count the number of timeseries of each node at the given level in current Metadata Tree. This could be used to query the number of sensors under each device. The grammar is: `COUNT TIMESERIES <Path> GROUP BY LEVEL=<INTEGER>`.

For example, if there are several timeseries (use `show timeseries` to show all timeseries):
<center><img style="width:100%; max-width:800px; margin-left:auto; margin-right:auto; display:block;" src="https://user-images.githubusercontent.com/19167280/69792072-cdc8a480-1200-11ea-8cec-321fef618a12.png"></center>

```
+-------------------------------+--------+-------------+--------+--------+-----------+-------------------------------------------+--------------------------------------------------------+
| timeseries| alias|storage group|dataType|encoding|compression| tags| attributes|
+-------------------------------+--------+-------------+--------+--------+-----------+-------------------------------------------+--------------------------------------------------------+
|root.sgcc.wf03.wt01.temperature| null| root.sgcc| FLOAT| RLE| SNAPPY| null| null|
| root.sgcc.wf03.wt01.status| null| root.sgcc| BOOLEAN| PLAIN| SNAPPY| null| null|
| root.turbine.d1.s1|newAlias| root.turbine| FLOAT| RLE| SNAPPY|{"newTag1":"newV1","tag4":"v4","tag3":"v3"}|{"attr2":"v2","attr1":"newV1","attr4":"v4","attr3":"v3"}|
| root.ln.wf02.wt02.hardware| null| root.ln| TEXT| PLAIN| SNAPPY| {"unit":"c"}| null|
| root.ln.wf02.wt02.status| null| root.ln| BOOLEAN| PLAIN| SNAPPY| {"description":"test1"}| null|
| root.ln.wf01.wt01.temperature| null| root.ln| FLOAT| RLE| SNAPPY| null| null|
| root.ln.wf01.wt01.status| null| root.ln| BOOLEAN| PLAIN| SNAPPY| null| null|
+-------------------------------+--------+-------------+--------+--------+-----------+-------------------------------------------+--------------------------------------------------------+
Total line number = 7
It costs 0.004s
```

Then the Metadata Tree will be as below:

<center><img style="width:100%; max-width:600px; margin-left:auto; margin-right:auto; display:block;" src="https://user-images.githubusercontent.com/19167280/69792176-1718f400-1201-11ea-861a-1a83c07ca144.jpg"></center>

As can be seen, `root` is considered as `LEVEL=0`. So when you enter statements such as:
Expand All @@ -244,7 +306,34 @@ IoTDB > COUNT TIMESERIES root.ln.wf01 GROUP BY LEVEL=2

You will get following results:

<center><img style="width:100%; max-width:800px; margin-left:auto; margin-right:auto; display:block;" src="https://user-images.githubusercontent.com/19167280/69792071-cb664a80-1200-11ea-8386-02dd12046c4b.png"></center>
```
+------------+-----+
| column|count|
+------------+-----+
| root.sgcc| 2|
|root.turbine| 1|
| root.ln| 4|
+------------+-----+
Total line number = 3
It costs 0.002s

+------------+-----+
| column|count|
+------------+-----+
|root.ln.wf02| 2|
|root.ln.wf01| 2|
+------------+-----+
Total line number = 2
It costs 0.002s

+------------+-----+
| column|count|
+------------+-----+
|root.ln.wf01| 2|
+------------+-----+
Total line number = 1
It costs 0.002s
```

> Note: The path of timeseries is just a filter condition, which has no relationship with the definition of level.

Expand All @@ -260,7 +349,31 @@ IoTDB > COUNT NODES root.ln.wf01 LEVEL=3

As for the above mentioned example and Metadata tree, you can get following results:

<center><img style="width:100%; max-width:800px; margin-left:auto; margin-right:auto; display:block;" src="https://user-images.githubusercontent.com/19167280/69792060-c73a2d00-1200-11ea-8ec4-be7145fd6c8c.png"></center>
```
+-----+
|count|
+-----+
| 4|
+-----+
Total line number = 1
It costs 0.003s

+-----+
|count|
+-----+
| 2|
+-----+
Total line number = 1
It costs 0.002s

+-----+
|count|
+-----+
| 1|
+-----+
Total line number = 1
It costs 0.002s
```

> Note: The path of timeseries is just a filter condition, which has no relationship with the definition of level.
`PrefixPath` could contains `*`, but all nodes after `*` would be ignored. Only the prefix path before `*` is valid.
Expand Down Expand Up @@ -291,6 +404,30 @@ IoTDB> show devices
IoTDB> show devices root.ln
```

You can get results below:

```
+-------------------+
| devices|
+-------------------+
| root.ln.wf01.wt01|
| root.ln.wf02.wt02|
|root.sgcc.wf03.wt01|
| root.turbine.d1|
+-------------------+
Total line number = 4
It costs 0.002s

+-----------------+
| devices|
+-----------------+
|root.ln.wf01.wt01|
|root.ln.wf02.wt02|
+-----------------+
Total line number = 2
It costs 0.001s
```

# TTL

IoTDB supports storage-level TTL settings, which means it is able to delete old data automatically and periodically. The benefit of using TTL is that hopefully you can control the total disk space usage and prevent the machine from running out of disks. Moreover, the query performance may downgrade as the total number of files goes up and the memory usage also increase as there are more files. Timely removing such files helps to keep at a high query performance level and reduce memory usage.
Expand All @@ -317,7 +454,7 @@ After unset TTL, all data will be accepted in `root.ln`

## Show TTL

To Show TTL, we can use follwing SQL statement:
To Show TTL, we can use following SQL statement:

```
IoTDB> SHOW ALL TTL
Expand Down
Loading