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new 0398b6b add a description of database and a tiered-store parameter
description (#153)
0398b6b is described below
commit 0398b6b69624964490ea8d5a0a1f0914fa0df09e
Author: wanghui42 <105700158+wanghu...@users.noreply.github.com>
AuthorDate: Thu Jan 18 15:32:33 2024 +0800
add a description of database and a tiered-store parameter description
(#153)
---
.../Basic-Concept/Data-Model-and-Terminology.md | 2 +
.../Master/User-Manual/Operate-Metadata.md | 123 ++++++++-------------
src/UserGuide/Master/User-Manual/Syntax-Rule.md | 3 +
.../Master/User-Manual/Tiered-Storage_timecho.md | 2 +-
.../Basic-Concept/Data-Model-and-Terminology.md | 2 +
.../latest/User-Manual/Operate-Metadata.md | 4 +-
src/UserGuide/latest/User-Manual/Syntax-Rule.md | 3 +
.../latest/User-Manual/Tiered-Storage_timecho.md | 2 +-
.../Basic-Concept/Data-Model-and-Terminology.md | 2 +-
.../Master/User-Manual/Operate-Metadata.md | 4 +-
src/zh/UserGuide/Master/User-Manual/Syntax-Rule.md | 3 +
.../Master/User-Manual/Tiered-Storage_timecho.md | 2 +-
.../Basic-Concept/Data-Model-and-Terminology.md | 2 +-
.../latest/User-Manual/Operate-Metadata.md | 33 +++++-
src/zh/UserGuide/latest/User-Manual/Syntax-Rule.md | 3 +
.../latest/User-Manual/Tiered-Storage_timecho.md | 2 +-
16 files changed, 108 insertions(+), 84 deletions(-)
diff --git a/src/UserGuide/Master/Basic-Concept/Data-Model-and-Terminology.md
b/src/UserGuide/Master/Basic-Concept/Data-Model-and-Terminology.md
index 7057074..92549ac 100644
--- a/src/UserGuide/Master/Basic-Concept/Data-Model-and-Terminology.md
+++ b/src/UserGuide/Master/Basic-Concept/Data-Model-and-Terminology.md
@@ -43,6 +43,8 @@ It is information measured by detection equipment in an
actual scene and can tra
**A group of entities.** Users can create any prefix path as a database.
Provided that there are four timeseries `root.ln.wf01.wt01.status`,
`root.ln.wf01.wt01.temperature`, `root.ln.wf02.wt02.hardware`,
`root.ln.wf02.wt02.status`, two devices `wt01`, `wt02` under the path `root.ln`
may belong to the same owner or the same manufacturer, so d1 and d2 are closely
related. At this point, the prefix path root.vehicle can be designated as a
database, which will enable IoTDB to store all devic [...]
+In general, it is recommended to create 1 database.
+
> Note1: A full path (`root.ln.wf01.wt01.status` as in the above example) is
> not allowed to be set as a database.
>
> Note2: The prefix of a timeseries must belong to a database. Before creating
> a timeseries, users must set which database the series belongs to. Only
> timeseries whose database is set can be persisted to disk.
diff --git a/src/UserGuide/Master/User-Manual/Operate-Metadata.md
b/src/UserGuide/Master/User-Manual/Operate-Metadata.md
index 2deeef1..4adb8e8 100644
--- a/src/UserGuide/Master/User-Manual/Operate-Metadata.md
+++ b/src/UserGuide/Master/User-Manual/Operate-Metadata.md
@@ -34,7 +34,9 @@ IoTDB > create database root.sgcc
We can thus create two databases 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 created as database, the path is then not allowed to be created
as database. For example, it is not feasible to create `root.ln.wf01` as
database when two databases `root.ln` and `root.sgcc` exist. The system gives
the corresponding error prompt as shown below:
+It is worth noting that 1 database is recommended.
+
+When the path itself or the parent/child layer of the path is already created
as database, the path is then not allowed to be created as database. For
example, it is not feasible to create `root.ln.wf01` as database when two
databases `root.ln` and `root.sgcc` exist. The system gives the corresponding
error prompt as shown below:
```
IoTDB> CREATE DATABASE root.ln.wf01
@@ -45,6 +47,8 @@ Msg: 300: root.ln has already been created as database.
The LayerName of database can only be characters, numbers, underscores. If you
want to set it to pure numbers or contain other characters, you need to enclose
the database name with backticks (``).
+Time series path supports the creation of hierarchical paths containing "*"
for paths other than the database level, e.g. root.db.`*`.
+
Besides, if deploy on Windows system, the LayerName is case-insensitive, which
means it's not allowed to create databases `root.ln` and `root.LN` at the same
time.
### Show Databases
@@ -317,7 +321,7 @@ Note: The `schema` keyword in the following statements can
be omitted.
### Create Schema Template
-The SQL syntax for creating a schema template is as follows:
+The SQL syntax for creating a metadata template is as follows:
```sql
CREATE SCHEMA TEMPLATE <templateName> ALIGNED? '(' <measurementId>
<attributeClauses> [',' <measurementId> <attributeClauses>]+ ')'
@@ -397,12 +401,12 @@ show devices root.sg1.**
````
```shell
-+---------------+---------+---------+
-| devices|isAligned| Template|
-+---------------+---------+---------+
-| root.sg1.d1| false| null|
-| root.sg1.d2| true| null|
-+---------------+---------+---------+
++---------------+---------+
+| devices|isAligned|
++---------------+---------+
+| root.sg1.d1| false|
+| root.sg1.d2| true|
++---------------+---------+
````
### Show Schema Template
@@ -1092,8 +1096,6 @@ 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.**`.
* `SHOW DEVICES <PathPattern>` statement specifies the `PathPattern` and
returns the devices information matching the pathPattern and under the given
level.
* `WHERE` condition supports `DEVICE contains 'xxx'` to do a fuzzy query
based on the device name.
-* `WHERE` condition supports `TEMPLATE = 'xxx'`,`TEMPLATE != 'xxx'` to do a
filter query based on the template name.
-* `WHERE` condition supports `TEMPLATE is null`,`TEMPLATE is not null` to do a
filter query based on whether the template is null (null indicating it's
inactive)
SQL statement is as follows:
@@ -1101,60 +1103,33 @@ SQL statement is as follows:
IoTDB> show devices
IoTDB> show devices root.ln.**
IoTDB> show devices root.ln.** where device contains 't'
-IoTDB> show devices root.ln.** where template = 't1'
-IoTDB> show devices root.ln.** where template is null
```
You can get results below:
```
-+-------------------+---------+---------+
-| devices|isAligned| Template|
-+-------------------+---------+---------+
-| root.ln.wf01.wt01| false| t1|
-| root.ln.wf02.wt02| false| null|
-|root.sgcc.wf03.wt01| false| null|
-| root.turbine.d1| false| null|
-+-------------------+---------+---------+
++-------------------+---------+
+| devices|isAligned|
++-------------------+---------+
+| root.ln.wf01.wt01| false|
+| root.ln.wf02.wt02| false|
+|root.sgcc.wf03.wt01| false|
+| root.turbine.d1| false|
++-------------------+---------+
Total line number = 4
It costs 0.002s
-+-----------------+---------+---------+
-| devices|isAligned| Template|
-+-----------------+---------+---------+
-|root.ln.wf01.wt01| false| t1|
-|root.ln.wf02.wt02| false| null|
-+-----------------+---------+---------+
-Total line number = 2
-It costs 0.001s
-
-+-----------------+---------+---------+
-| devices|isAligned| Template|
-+-----------------+---------+---------+
-|root.ln.wf01.wt01| false| t1|
-|root.ln.wf02.wt02| false| null|
-+-----------------+---------+---------+
++-----------------+---------+
+| devices|isAligned|
++-----------------+---------+
+|root.ln.wf01.wt01| false|
+|root.ln.wf02.wt02| false|
++-----------------+---------+
Total line number = 2
It costs 0.001s
-
-+-----------------+---------+---------+
-| devices|isAligned| Template|
-+-----------------+---------+---------+
-|root.ln.wf01.wt01| false| t1|
-+-----------------+---------+---------+
-Total line number = 1
-It costs 0.001s
-
-+-----------------+---------+---------+
-| devices|isAligned| Template|
-+-----------------+---------+---------+
-|root.ln.wf02.wt02| false| null|
-+-----------------+---------+---------+
-Total line number = 1
-It costs 0.001s
```
-`isAligned` indicates whether the timeseries under the device are aligned,
`Template` displays the name of the template activated on the device, with
`null` indicating that no template has been activated.
+`isAligned` indicates whether the timeseries under the device are aligned.
To view devices' information with database, we can use `SHOW DEVICES WITH
DATABASE` statement.
@@ -1172,23 +1147,23 @@ IoTDB> show devices root.ln.** with database
You can get results below:
```
-+-------------------+-------------+---------+---------+
-| devices| database|isAligned| Template|
-+-------------------+-------------+---------+---------+
-| root.ln.wf01.wt01| root.ln| false| t1|
-| root.ln.wf02.wt02| root.ln| false| null|
-|root.sgcc.wf03.wt01| root.sgcc| false| null|
-| root.turbine.d1| root.turbine| false| null|
-+-------------------+-------------+---------+---------+
++-------------------+-------------+---------+
+| devices| database|isAligned|
++-------------------+-------------+---------+
+| root.ln.wf01.wt01| root.ln| false|
+| root.ln.wf02.wt02| root.ln| false|
+|root.sgcc.wf03.wt01| root.sgcc| false|
+| root.turbine.d1| root.turbine| false|
++-------------------+-------------+---------+
Total line number = 4
It costs 0.003s
-+-----------------+-------------+---------+---------+
-| devices| database|isAligned| Template|
-+-----------------+-------------+---------+---------+
-|root.ln.wf01.wt01| root.ln| false| t1|
-|root.ln.wf02.wt02| root.ln| false| null|
-+-----------------+-------------+---------+---------+
++-----------------+-------------+---------+
+| devices| database|isAligned|
++-----------------+-------------+---------+
+|root.ln.wf01.wt01| root.ln| false|
+|root.ln.wf02.wt02| root.ln| false|
++-----------------+-------------+---------+
Total line number = 2
It costs 0.001s
```
@@ -1210,14 +1185,14 @@ IoTDB> count devices root.ln.**
You can get results below:
```
-+-------------------+---------+---------+
-| devices|isAligned| Template|
-+-------------------+---------+---------+
-|root.sgcc.wf03.wt03| false| null|
-| root.turbine.d1| false| null|
-| root.ln.wf02.wt02| false| null|
-| root.ln.wf01.wt01| false| t1|
-+-------------------+---------+---------+
++-------------------+---------+
+| devices|isAligned|
++-------------------+---------+
+|root.sgcc.wf03.wt03| false|
+| root.turbine.d1| false|
+| root.ln.wf02.wt02| false|
+| root.ln.wf01.wt01| false|
++-------------------+---------+
Total line number = 4
It costs 0.024s
diff --git a/src/UserGuide/Master/User-Manual/Syntax-Rule.md
b/src/UserGuide/Master/User-Manual/Syntax-Rule.md
index 4ee0560..4567a6f 100644
--- a/src/UserGuide/Master/User-Manual/Syntax-Rule.md
+++ b/src/UserGuide/Master/User-Manual/Syntax-Rule.md
@@ -275,6 +275,9 @@ Examples of case in which quoted identifier is used ：
```
- The key/value of an attribute can be String Literal and identifier, more
details can be found at **key-value pair** part.
+
+- Time series path supports the creation of hierarchical paths containing "*"
for paths other than the database level, e.g. root.db.`*`.
+
## KeyWords Words
diff --git a/src/UserGuide/Master/User-Manual/Tiered-Storage_timecho.md
b/src/UserGuide/Master/User-Manual/Tiered-Storage_timecho.md
index 3fe5792..7c9b100 100644
--- a/src/UserGuide/Master/User-Manual/Tiered-Storage_timecho.md
+++ b/src/UserGuide/Master/User-Manual/Tiered-Storage_timecho.md
@@ -37,7 +37,7 @@ The specific parameter definitions and their descriptions are
as follows.
| Configuration | Default
| Description |
Constraint |
| ---------------------------------------- | ------------------------ |
------------------------------------------------------------ |
------------------------------------------------------------ |
| dn_data_dirs | None |
specify different storage directories and divide the storage directories into
tiers | Each level of storage uses a semicolon to separate, and
commas to separate within a single level; cloud (OBJECT_STORAGE) configuration
can only be used as the last level of storage and the first level can't be used
as cloud storage; a cloud object at most; the remote storage directory is
denoted by OBJECT_STORAGE |
-| default_ttl_in_ms | None |
Define the maximum age of data for which each tier is responsible
| Each level of storage is separated by a semicolon; the number of levels
should match the number of levels defined by dn_data_dirs |
+| default_ttl_in_ms | None |
Define the maximum age of data for which each tier is responsible
| Each level of storage is separated by a semicolon; the number of levels
should match the number of levels defined by dn_data_dirs；"-1" means
"unlimited". |
| dn_default_space_move_thresholds | 0.15 | Define
the minimum remaining space ratio for each tier data catalogue; when the
remaining space is less than this ratio, the data will be automatically
migrated to the next tier; when the remaining storage space of the last tier
falls below this threshold, the system will be set to READ_ONLY | Each level of
storage is separated by a semicolon; the number of levels should match the
number of levels defined by dn_data_dirs |
| object_storage_type | AWS_S3 | Cloud
Storage Type | IoTDB currently
only supports AWS S3 as a remote storage type, and this parameter can't be
modified |
| object_storage_bucket | None |
Name of cloud storage bucket | Bucket
definition in AWS S3; no need to configure if remote storage is not used
|
diff --git a/src/UserGuide/latest/Basic-Concept/Data-Model-and-Terminology.md
b/src/UserGuide/latest/Basic-Concept/Data-Model-and-Terminology.md
index 7057074..92549ac 100644
--- a/src/UserGuide/latest/Basic-Concept/Data-Model-and-Terminology.md
+++ b/src/UserGuide/latest/Basic-Concept/Data-Model-and-Terminology.md
@@ -43,6 +43,8 @@ It is information measured by detection equipment in an
actual scene and can tra
**A group of entities.** Users can create any prefix path as a database.
Provided that there are four timeseries `root.ln.wf01.wt01.status`,
`root.ln.wf01.wt01.temperature`, `root.ln.wf02.wt02.hardware`,
`root.ln.wf02.wt02.status`, two devices `wt01`, `wt02` under the path `root.ln`
may belong to the same owner or the same manufacturer, so d1 and d2 are closely
related. At this point, the prefix path root.vehicle can be designated as a
database, which will enable IoTDB to store all devic [...]
+In general, it is recommended to create 1 database.
+
> Note1: A full path (`root.ln.wf01.wt01.status` as in the above example) is
> not allowed to be set as a database.
>
> Note2: The prefix of a timeseries must belong to a database. Before creating
> a timeseries, users must set which database the series belongs to. Only
> timeseries whose database is set can be persisted to disk.
diff --git a/src/UserGuide/latest/User-Manual/Operate-Metadata.md
b/src/UserGuide/latest/User-Manual/Operate-Metadata.md
index 7f10fe7..1ed3ac0 100644
--- a/src/UserGuide/latest/User-Manual/Operate-Metadata.md
+++ b/src/UserGuide/latest/User-Manual/Operate-Metadata.md
@@ -34,7 +34,9 @@ IoTDB > create database root.sgcc
We can thus create two databases 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 created as database, the path is then not allowed to be created
as database. For example, it is not feasible to create `root.ln.wf01` as
database when two databases `root.ln` and `root.sgcc` exist. The system gives
the corresponding error prompt as shown below:
+It is worth noting that 1 database is recommended.
+
+When the path itself or the parent/child layer of the path is already created
as database, the path is then not allowed to be created as database. For
example, it is not feasible to create `root.ln.wf01` as database when two
databases `root.ln` and `root.sgcc` exist. The system gives the corresponding
error prompt as shown below:
```
IoTDB> CREATE DATABASE root.ln.wf01
diff --git a/src/UserGuide/latest/User-Manual/Syntax-Rule.md
b/src/UserGuide/latest/User-Manual/Syntax-Rule.md
index 4ee0560..4567a6f 100644
--- a/src/UserGuide/latest/User-Manual/Syntax-Rule.md
+++ b/src/UserGuide/latest/User-Manual/Syntax-Rule.md
@@ -275,6 +275,9 @@ Examples of case in which quoted identifier is used ：
```
- The key/value of an attribute can be String Literal and identifier, more
details can be found at **key-value pair** part.
+
+- Time series path supports the creation of hierarchical paths containing "*"
for paths other than the database level, e.g. root.db.`*`.
+
## KeyWords Words
diff --git a/src/UserGuide/latest/User-Manual/Tiered-Storage_timecho.md
b/src/UserGuide/latest/User-Manual/Tiered-Storage_timecho.md
index 3fe5792..7c9b100 100644
--- a/src/UserGuide/latest/User-Manual/Tiered-Storage_timecho.md
+++ b/src/UserGuide/latest/User-Manual/Tiered-Storage_timecho.md
@@ -37,7 +37,7 @@ The specific parameter definitions and their descriptions are
as follows.
| Configuration | Default
| Description |
Constraint |
| ---------------------------------------- | ------------------------ |
------------------------------------------------------------ |
------------------------------------------------------------ |
| dn_data_dirs | None |
specify different storage directories and divide the storage directories into
tiers | Each level of storage uses a semicolon to separate, and
commas to separate within a single level; cloud (OBJECT_STORAGE) configuration
can only be used as the last level of storage and the first level can't be used
as cloud storage; a cloud object at most; the remote storage directory is
denoted by OBJECT_STORAGE |
-| default_ttl_in_ms | None |
Define the maximum age of data for which each tier is responsible
| Each level of storage is separated by a semicolon; the number of levels
should match the number of levels defined by dn_data_dirs |
+| default_ttl_in_ms | None |
Define the maximum age of data for which each tier is responsible
| Each level of storage is separated by a semicolon; the number of levels
should match the number of levels defined by dn_data_dirs；"-1" means
"unlimited". |
| dn_default_space_move_thresholds | 0.15 | Define
the minimum remaining space ratio for each tier data catalogue; when the
remaining space is less than this ratio, the data will be automatically
migrated to the next tier; when the remaining storage space of the last tier
falls below this threshold, the system will be set to READ_ONLY | Each level of
storage is separated by a semicolon; the number of levels should match the
number of levels defined by dn_data_dirs |
| object_storage_type | AWS_S3 | Cloud
Storage Type | IoTDB currently
only supports AWS S3 as a remote storage type, and this parameter can't be
modified |
| object_storage_bucket | None |
Name of cloud storage bucket | Bucket
definition in AWS S3; no need to configure if remote storage is not used
|
diff --git
a/src/zh/UserGuide/Master/Basic-Concept/Data-Model-and-Terminology.md
b/src/zh/UserGuide/Master/Basic-Concept/Data-Model-and-Terminology.md
index 8ae3e7e..930dab1 100644
--- a/src/zh/UserGuide/Master/Basic-Concept/Data-Model-and-Terminology.md
+++ b/src/zh/UserGuide/Master/Basic-Concept/Data-Model-and-Terminology.md
@@ -35,7 +35,7 @@ IoTDB 模型结构涉及的基本概念在下文将做详细叙述。
用户可以将任意前缀路径设置成数据库。如有 4 条时间序列`root.ln.wf01.wt01.status`,
`root.ln.wf01.wt01.temperature`, `root.ln.wf02.wt02.hardware`,
`root.ln.wf02.wt02.status`，路径`root.ln`下的两个实体 `wt01`,
`wt02`可能属于同一个业主，或者同一个制造商，这时候就可以将前缀路径`root.ln`指定为一个数据库。未来`root.ln`下增加了新的实体，也将属于该数据库。
-一个 database 中的所有数据会存储在同一批文件夹下，不同 database 的数据会存储在磁盘的不同文件夹下，从而实现物理隔离。
+一个 database 中的所有数据会存储在同一批文件夹下，不同 database 的数据会存储在磁盘的不同文件夹下，从而实现物理隔离。一般情况下建议设置
1 个 database。
> 注意 1：不允许将一个完整路径（如上例的`root.ln.wf01.wt01.status`) 设置成 database。
>
diff --git a/src/zh/UserGuide/Master/User-Manual/Operate-Metadata.md
b/src/zh/UserGuide/Master/User-Manual/Operate-Metadata.md
index 53ef593..54aea41 100644
--- a/src/zh/UserGuide/Master/User-Manual/Operate-Metadata.md
+++ b/src/zh/UserGuide/Master/User-Manual/Operate-Metadata.md
@@ -32,7 +32,9 @@
IoTDB > CREATE DATABASE root.ln
```
-需要注意的是，database 的父子节点都不能再设置 database。例如在已经有`root.ln`和`root.sgcc`这两个 database
的情况下，创建`root.ln.wf01` database 是不可行的。系统将给出相应的错误提示，如下所示：
+需要注意的是，推荐创建一个 database.
+
+Database 的父子节点都不能再设置 database。例如在已经有`root.ln`和`root.sgcc`这两个 database
的情况下，创建`root.ln.wf01` database 是不可行的。系统将给出相应的错误提示，如下所示：
```
IoTDB> CREATE DATABASE root.ln.wf01
diff --git a/src/zh/UserGuide/Master/User-Manual/Syntax-Rule.md
b/src/zh/UserGuide/Master/User-Manual/Syntax-Rule.md
index 697068a..c70bb41 100644
--- a/src/zh/UserGuide/Master/User-Manual/Syntax-Rule.md
+++ b/src/zh/UserGuide/Master/User-Manual/Syntax-Rule.md
@@ -271,6 +271,9 @@ create schema template `t1't"t`
```
- 用于表示键值对，键值对的键和值可以被定义成常量（包括字符串）或者标识符，具体请参考键值对章节。
+
+- 时间序列路径中对于 database 级别以外的层级路径支持含有"*"创建，如 root.db.`*`。
+
## 关键字
diff --git a/src/zh/UserGuide/Master/User-Manual/Tiered-Storage_timecho.md
b/src/zh/UserGuide/Master/User-Manual/Tiered-Storage_timecho.md
index 5b5e201..b368f16 100644
--- a/src/zh/UserGuide/Master/User-Manual/Tiered-Storage_timecho.md
+++ b/src/zh/UserGuide/Master/User-Manual/Tiered-Storage_timecho.md
@@ -37,7 +37,7 @@
| 配置项 | 默认值 | 说明
| 约束
|
| ---------------------------------------- | ------------------------ |
------------------------------------------------------------ |
------------------------------------------------------------ |
| dn_data_dirs | 无 |
用来指定不同的存储目录，并将存储目录进行层级划分 |
每级存储使用分号分隔，单级内使用逗号分隔；云端配置只能作为最后一级存储且第一级不能作为云端存储；最多配置一个云端对象；远端存储目录使用
OBJECT_STORAGE 来表示 |
-| default_ttl_in_ms | 无 |
定义每个层级负责的数据范围，通过 TTL 表示 | 每级存储使用分号分隔；层级数量需与 dn_data_dirs
定义的层级数一致 |
+| default_ttl_in_ms | 无 |
定义每个层级负责的数据范围，通过 TTL 表示 | 每级存储使用分号分隔；层级数量需与 dn_data_dirs
定义的层级数一致；"-1" 表示"无限制" |
| dn_default_space_move_thresholds | 0.15 |
定义每个层级数据目录的最小剩余空间比例；当剩余空间少于该比例时，数据会被自动迁移至下一个层级；当最后一个层级的剩余存储空间到低于此阈值时，会将系统置为
READ_ONLY | 每级存储使用分号分隔；层级数量需与 dn_data_dirs 定义的层级数一致 |
| object_storage_type | AWS_S3 | 云端存储类型
| IoTDB 当前只支持 AWS S3
作为远端存储类型，此参数不支持修改 |
| object_storage_bucket | 无 | 云端存储
bucket 的名称 | AWS S3 中的 bucket
定义；如果未使用远端存储，无需配置 |
diff --git
a/src/zh/UserGuide/latest/Basic-Concept/Data-Model-and-Terminology.md
b/src/zh/UserGuide/latest/Basic-Concept/Data-Model-and-Terminology.md
index 8ae3e7e..930dab1 100644
--- a/src/zh/UserGuide/latest/Basic-Concept/Data-Model-and-Terminology.md
+++ b/src/zh/UserGuide/latest/Basic-Concept/Data-Model-and-Terminology.md
@@ -35,7 +35,7 @@ IoTDB 模型结构涉及的基本概念在下文将做详细叙述。
用户可以将任意前缀路径设置成数据库。如有 4 条时间序列`root.ln.wf01.wt01.status`,
`root.ln.wf01.wt01.temperature`, `root.ln.wf02.wt02.hardware`,
`root.ln.wf02.wt02.status`，路径`root.ln`下的两个实体 `wt01`,
`wt02`可能属于同一个业主，或者同一个制造商，这时候就可以将前缀路径`root.ln`指定为一个数据库。未来`root.ln`下增加了新的实体，也将属于该数据库。
-一个 database 中的所有数据会存储在同一批文件夹下，不同 database 的数据会存储在磁盘的不同文件夹下，从而实现物理隔离。
+一个 database 中的所有数据会存储在同一批文件夹下，不同 database 的数据会存储在磁盘的不同文件夹下，从而实现物理隔离。一般情况下建议设置
1 个 database。
> 注意 1：不允许将一个完整路径（如上例的`root.ln.wf01.wt01.status`) 设置成 database。
>
diff --git a/src/zh/UserGuide/latest/User-Manual/Operate-Metadata.md
b/src/zh/UserGuide/latest/User-Manual/Operate-Metadata.md
index 9d7c57e..b76f130 100644
--- a/src/zh/UserGuide/latest/User-Manual/Operate-Metadata.md
+++ b/src/zh/UserGuide/latest/User-Manual/Operate-Metadata.md
@@ -32,7 +32,9 @@
IoTDB > CREATE DATABASE root.ln
```
-需要注意的是，database 的父子节点都不能再设置 database。例如在已经有`root.ln`和`root.sgcc`这两个 database
的情况下，创建`root.ln.wf01` database 是不可行的。系统将给出相应的错误提示，如下所示：
+需要注意的是，推荐创建一个 database.
+
+Database 的父子节点都不能再设置 database。例如在已经有`root.ln`和`root.sgcc`这两个 database
的情况下，创建`root.ln.wf01` database 是不可行的。系统将给出相应的错误提示，如下所示：
```
IoTDB> CREATE DATABASE root.ln.wf01
@@ -1072,6 +1074,8 @@ SQL 语句如下所示：
IoTDB> show devices
IoTDB> show devices root.ln.**
IoTDB> show devices root.ln.** where device contains 't'
+IoTDB> show devices root.ln.** where template = 't1'
+IoTDB> show devices root.ln.** where template is null
```
你可以获得如下数据：
@@ -1096,9 +1100,34 @@ It costs 0.002s
+-----------------+---------+
Total line number = 2
It costs 0.001s
+
++-----------------+---------+---------+
+| devices|isAligned| Template|
++-----------------+---------+---------+
+|root.ln.wf01.wt01| false| t1|
+|root.ln.wf02.wt02| false| null|
++-----------------+---------+---------+
+Total line number = 2
+It costs 0.001s
+
++-----------------+---------+---------+
+| devices|isAligned| Template|
++-----------------+---------+---------+
+|root.ln.wf01.wt01| false| t1|
++-----------------+---------+---------+
+Total line number = 1
+It costs 0.001s
+
++-----------------+---------+---------+
+| devices|isAligned| Template|
++-----------------+---------+---------+
+|root.ln.wf02.wt02| false| null|
++-----------------+---------+---------+
+Total line number = 1
+It costs 0.001s
```
-其中，`isAligned`表示该设备下的时间序列是否对齐。
+其中，`isAligned`表示该设备下的时间序列是否对齐,
查看设备及其 database 信息，可以使用 `SHOW DEVICES WITH DATABASE` 语句。
diff --git a/src/zh/UserGuide/latest/User-Manual/Syntax-Rule.md
b/src/zh/UserGuide/latest/User-Manual/Syntax-Rule.md
index 697068a..c70bb41 100644
--- a/src/zh/UserGuide/latest/User-Manual/Syntax-Rule.md
+++ b/src/zh/UserGuide/latest/User-Manual/Syntax-Rule.md
@@ -271,6 +271,9 @@ create schema template `t1't"t`
```
- 用于表示键值对，键值对的键和值可以被定义成常量（包括字符串）或者标识符，具体请参考键值对章节。
+
+- 时间序列路径中对于 database 级别以外的层级路径支持含有"*"创建，如 root.db.`*`。
+
## 关键字
diff --git a/src/zh/UserGuide/latest/User-Manual/Tiered-Storage_timecho.md
b/src/zh/UserGuide/latest/User-Manual/Tiered-Storage_timecho.md
index 5b5e201..b368f16 100644
--- a/src/zh/UserGuide/latest/User-Manual/Tiered-Storage_timecho.md
+++ b/src/zh/UserGuide/latest/User-Manual/Tiered-Storage_timecho.md
@@ -37,7 +37,7 @@
| 配置项 | 默认值 | 说明
| 约束
|
| ---------------------------------------- | ------------------------ |
------------------------------------------------------------ |
------------------------------------------------------------ |
| dn_data_dirs | 无 |
用来指定不同的存储目录，并将存储目录进行层级划分 |
每级存储使用分号分隔，单级内使用逗号分隔；云端配置只能作为最后一级存储且第一级不能作为云端存储；最多配置一个云端对象；远端存储目录使用
OBJECT_STORAGE 来表示 |
-| default_ttl_in_ms | 无 |
定义每个层级负责的数据范围，通过 TTL 表示 | 每级存储使用分号分隔；层级数量需与 dn_data_dirs
定义的层级数一致 |
+| default_ttl_in_ms | 无 |
定义每个层级负责的数据范围，通过 TTL 表示 | 每级存储使用分号分隔；层级数量需与 dn_data_dirs
定义的层级数一致；"-1" 表示"无限制" |
| dn_default_space_move_thresholds | 0.15 |
定义每个层级数据目录的最小剩余空间比例；当剩余空间少于该比例时，数据会被自动迁移至下一个层级；当最后一个层级的剩余存储空间到低于此阈值时，会将系统置为
READ_ONLY | 每级存储使用分号分隔；层级数量需与 dn_data_dirs 定义的层级数一致 |
| object_storage_type | AWS_S3 | 云端存储类型
| IoTDB 当前只支持 AWS S3
作为远端存储类型，此参数不支持修改 |
| object_storage_bucket | 无 | 云端存储
bucket 的名称 | AWS S3 中的 bucket
定义；如果未使用远端存储，无需配置 |
