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Posted to notifications@shardingsphere.apache.org by zh...@apache.org on 2023/06/26 10:15:59 UTC
[shardingsphere] branch master updated: Fixes #22887, add docs for single tables. (#26582)
This is an automated email from the ASF dual-hosted git repository.
zhaojinchao pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/shardingsphere.git
The following commit(s) were added to refs/heads/master by this push:
new 05956d176c1 Fixes #22887, add docs for single tables. (#26582)
05956d176c1 is described below
commit 05956d176c111b24eb508db6f878e2b69c1913ab
Author: Raigor <ra...@gmail.com>
AuthorDate: Mon Jun 26 18:15:52 2023 +0800
Fixes #22887, add docs for single tables. (#26582)
---
.../content/features/sharding/concept.cn.md | 6 ++
.../content/features/sharding/concept.en.md | 6 ++
.../yaml-config/rules/single.cn.md | 30 ++++++++++
.../yaml-config/rules/single.en.md | 30 ++++++++++
.../single-table/load-single-table.cn.md | 69 +++++++++++++++++++++
.../single-table/load-single-table.en.md | 70 ++++++++++++++++++++++
.../set-default-single-table-storage-unit.cn.md | 2 +-
.../set-default-single-table-storage-unit.en.md | 2 +-
.../single-table/unload-single-table.cn.md | 56 +++++++++++++++++
.../single-table/unload-single-table.en.md | 57 ++++++++++++++++++
.../single-table/show-single-table.cn.md | 38 ++++++------
.../single-table/show-single-table.en.md | 48 +++++++--------
.../single-table/show-unloaded-single-tables.cn.md | 57 ++++++++++++++++++
.../single-table/show-unloaded-single-tables.en.md | 56 +++++++++++++++++
14 files changed, 482 insertions(+), 45 deletions(-)
diff --git a/docs/document/content/features/sharding/concept.cn.md b/docs/document/content/features/sharding/concept.cn.md
index 2ee35668426..694a839cbb1 100644
--- a/docs/document/content/features/sharding/concept.cn.md
+++ b/docs/document/content/features/sharding/concept.cn.md
@@ -53,6 +53,12 @@ SELECT i.* FROM t_order_1 o JOIN t_order_item_1 i ON o.order_id=i.order_id WHERE
指所有的分片数据源中仅唯一存在的表。 适用于数据量不大且无需分片的表。
+注意：符合以下条件的单表会被自动加载：
+- 数据加密、数据脱敏等规则中显示配置的单表
+- 用户通过 ShardingSphere 执行 DDL 语句创建的单表
+
+其余不符合上述条件的单表，ShardingSphere 不会自动加载，用户可根据需要配置单表规则进行管理。
+
## 数据节点
数据分片的最小单元，由数据源名称和真实表组成。 例：ds_0.t_order_0。
diff --git a/docs/document/content/features/sharding/concept.en.md b/docs/document/content/features/sharding/concept.en.md
index d9653e41d80..96fe920fb89 100644
--- a/docs/document/content/features/sharding/concept.en.md
+++ b/docs/document/content/features/sharding/concept.en.md
@@ -58,6 +58,12 @@ Refers to tables that exist in all data sources. The table structure and its dat
Refers to the only table that exists in all sharded data sources. Suitable for tables with a small amount of data and do not need to be sharded.
+Note: Single tables that meet the following conditions will be automatically loaded:
+- A single table showing the configuration in rules such as encrypt and mask
+- A single table created by users executing DDL statements through ShardingSphere
+
+For other single tables that do not meet the above conditions, ShardingSphere will not automatically load them, and users can configure single table rules as needed for management.
+
## Data Nodes
The smallest unit of the data shard, consists of the data source name and the real table. Example: `ds_0.t_order_0`.
diff --git a/docs/document/content/user-manual/shardingsphere-jdbc/yaml-config/rules/single.cn.md b/docs/document/content/user-manual/shardingsphere-jdbc/yaml-config/rules/single.cn.md
new file mode 100644
index 00000000000..a8762d3c249
--- /dev/null
+++ b/docs/document/content/user-manual/shardingsphere-jdbc/yaml-config/rules/single.cn.md
@@ -0,0 +1,30 @@
++++
+title = "单表"
+weight = 12
++++
+
+## 背景信息
+
+单表规则用于指定哪些单表需要被 ShardingSphere 管理，也可设置默认的单表数据源。
+
+## 参数解释
+
+```yaml
+rules:
+- !SINGLE
+ tables:
+ # MySQL 风格
+ - ds_0.t_single # 加载指定单表
+ - ds_1.* # 加载指定数据源中的全部单表
+ - "*.*" # 加载全部单表
+ # PostgreSQL 风格
+ - ds_0.public.t_config
+ - ds_1.public.*
+ - ds_2.*.*
+ - "*.*.*"
+ defaultDataSource: ds_0 # 默认数据源，仅在执行 CREATE TABLE 创建单表时有效。缺失值为空，表示随机单播路由。
+```
+
+## 相关参考
+
+- [单表](/cn/features/sharding/concept/#单表)
diff --git a/docs/document/content/user-manual/shardingsphere-jdbc/yaml-config/rules/single.en.md b/docs/document/content/user-manual/shardingsphere-jdbc/yaml-config/rules/single.en.md
new file mode 100644
index 00000000000..f6be197727e
--- /dev/null
+++ b/docs/document/content/user-manual/shardingsphere-jdbc/yaml-config/rules/single.en.md
@@ -0,0 +1,30 @@
++++
+title = "Single Table"
+weight = 12
++++
+
+## Background
+
+Single rule is used to specify which single tables need to be managed by ShardingSphere, or to set the default single table data source.
+
+## Parameters
+
+```yaml
+rules:
+- !SINGLE
+ tables:
+ # MySQL style
+ - ds_0.t_single # Load specified single table
+ - ds_1.* # Load all single tables in the specified data source
+ - "*.*" # Load all single tables
+ # PostgreSQL style
+ - ds_0.public.t_config
+ - ds_1.public.*
+ - ds_2.*.*
+ - "*.*.*"
+ defaultDataSource: ds_0 # The default data source is used when executing CREATE TABLE statement to create a single table. The default value is null, indicating random unicast routing.
+```
+
+## Related References
+
+- [Single Table](en/features/sharding/concept/#single-table)
diff --git a/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/load-single-table.cn.md b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/load-single-table.cn.md
new file mode 100644
index 00000000000..4819500af22
--- /dev/null
+++ b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/load-single-table.cn.md
@@ -0,0 +1,69 @@
++++
+title = "LOAD SINGLE TABLE"
+weight = 1
++++
+
+## 描述
+
+`LOAD SINGLE TABLE` 用于加载单表。
+
+### 语法定义
+
+{{< tabs >}}
+{{% tab name="语法" %}}
+```sql
+loadSingleTable ::=
+ 'LOAD' 'SINGLE' 'TABLE' tableDefinition
+
+tableDefinition ::=
+ tableIdentifier (',' tableIdentifier)*
+
+tableIdentifier ::=
+ '*.*' | '*.*.*' | storageUnitName '.*' | storageUnitName '.*.*' | storageUnitName '.' schemaName '.*' | storageUnitName '.' tableName | storageUnitName '.' schemaName '.' tableName
+
+storageUnitName ::=
+ identifier
+
+schemaName ::=
+ identifier
+
+tableName ::=
+ identifier
+```
+{{% /tab %}}
+{{% tab name="铁路图" %}}
+<iframe frameborder="0" name="diagram" id="diagram" width="100%" height="100%"></iframe>
+{{% /tab %}}
+{{< /tabs >}}
+
+### 补充说明
+
+- PostgreSQL 和 OpenGauss 协议下支持指定 schemaName
+
+### 示例
+
+- 加载指定单表
+
+```sql
+LOAD SINGLE TABLE ds_0.t_single;
+```
+
+- 加载指定存储节点中的全部单表
+
+```sql
+LOAD SINGLE TABLE ds_0.*;
+```
+
+- 加载全部单表
+
+```sql
+LOAD SINGLE TABLE *.*;
+```
+
+### 保留字
+
+`LOAD`、`SINGLE`、`TABLE`
+
+### 相关链接
+
+- [保留字](/cn/user-manual/shardingsphere-proxy/distsql/syntax/reserved-word/)
\ No newline at end of file
diff --git a/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/load-single-table.en.md b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/load-single-table.en.md
new file mode 100644
index 00000000000..0f1d764031e
--- /dev/null
+++ b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/load-single-table.en.md
@@ -0,0 +1,70 @@
++++
+title = "LOAD SINGLE TABLE"
+weight = 1
++++
+
+## Description
+
+The `LOAD SINGLE TABLE` syntax is used to load single table from storage unit.
+
+### Syntax
+
+{{< tabs >}}
+{{% tab name="Grammar" %}}
+```sql
+loadSingleTable ::=
+ 'LOAD' 'SINGLE' 'TABLE' tableDefinition
+
+tableDefinition ::=
+ tableIdentifier (',' tableIdentifier)*
+
+tableIdentifier ::=
+ '*.*' | '*.*.*' | storageUnitName '.*' | storageUnitName '.*.*' | storageUnitName '.' schemaName '.*' | storageUnitName '.' tableName | storageUnitName '.' schemaName '.' tableName
+
+storageUnitName ::=
+ identifier
+
+schemaName ::=
+ identifier
+
+tableName ::=
+ identifier
+```
+{{% /tab %}}
+{{% tab name="Railroad diagram" %}}
+<iframe frameborder="0" name="diagram" id="diagram" width="100%" height="100%"></iframe>
+{{% /tab %}}
+{{< /tabs >}}
+
+### Supplement
+
+- support specifying schemaName in PostgreSQL and OpenGauss protocols
+
+
+### Example
+
+- Load specified single table
+
+```sql
+LOAD SINGLE TABLE ds_0.t_single;
+```
+
+- Load all single tables in the specified storage unit
+
+```sql
+LOAD SINGLE TABLE ds_0.*;
+```
+
+- Load all single tables
+
+```sql
+LOAD SINGLE TABLE *.*;
+```
+
+### Reserved word
+
+`LOAD`, `SINGLE`, `TABLE`
+
+### Related links
+
+- [Reserved word](/en/user-manual/shardingsphere-proxy/distsql/syntax/reserved-word/)
diff --git a/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/set-default-single-table-storage-unit.cn.md b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/set-default-single-table-storage-unit.cn.md
index c2adcdf2aab..da48cc76e20 100644
--- a/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/set-default-single-table-storage-unit.cn.md
+++ b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/set-default-single-table-storage-unit.cn.md
@@ -1,6 +1,6 @@
+++
title = "SET DEFAULT SINGLE TABLE STORAGE UNIT"
-weight = 1
+weight = 3
+++
## 描述
diff --git a/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/set-default-single-table-storage-unit.en.md b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/set-default-single-table-storage-unit.en.md
index 118bb1a41f8..adc3933fc4f 100644
--- a/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/set-default-single-table-storage-unit.en.md
+++ b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/set-default-single-table-storage-unit.en.md
@@ -1,6 +1,6 @@
+++
title = "SET DEFAULT SINGLE TABLE STORAGE UNIT"
-weight = 1
+weight = 3
+++
## Description
diff --git a/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/unload-single-table.cn.md b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/unload-single-table.cn.md
new file mode 100644
index 00000000000..5b0639904a3
--- /dev/null
+++ b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/unload-single-table.cn.md
@@ -0,0 +1,56 @@
++++
+title = "UNLOAD SINGLE TABLE"
+weight = 2
++++
+
+## 描述
+
+`UNLOAD SINGLE TABLE` 用于卸载单表。
+
+### 语法定义
+
+{{< tabs >}}
+{{% tab name="语法" %}}
+```sql
+unloadSingleTable ::=
+ 'UNLOAD' 'SINGLE' 'TABLE' tableNames
+
+tableNames ::=
+ tableName (',' tableName)*
+
+tableName ::=
+ identifier
+```
+{{% /tab %}}
+{{% tab name="铁路图" %}}
+<iframe frameborder="0" name="diagram" id="diagram" width="100%" height="100%"></iframe>
+{{% /tab %}}
+{{< /tabs >}}
+
+### 补充说明
+
+- 与加载不同，卸载单表时仅需指定表名
+
+### 示例
+
+- 卸载指定单表
+
+```sql
+UNLOAD SINGLE TABLE t_single;
+```
+
+- 卸载全部单表
+
+```sql
+UNLOAD SINGLE TABLE *;
+-- 或
+UNLOAD ALL SINGLE TABLES;
+```
+
+### 保留字
+
+`UNLOAD`、`SINGLE`、`TABLE` 、`ALL` 、`TABLES`
+
+### 相关链接
+
+- [保留字](/cn/user-manual/shardingsphere-proxy/distsql/syntax/reserved-word/)
\ No newline at end of file
diff --git a/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/unload-single-table.en.md b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/unload-single-table.en.md
new file mode 100644
index 00000000000..638349f52a4
--- /dev/null
+++ b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rdl/rule-definition/single-table/unload-single-table.en.md
@@ -0,0 +1,57 @@
++++
+title = "UNLOAD SINGLE TABLE"
+weight = 2
++++
+
+## Description
+
+The `UNLOAD SINGLE TABLE` syntax is used to unload single table.
+
+### Syntax
+
+{{< tabs >}}
+{{% tab name="Grammar" %}}
+```sql
+unloadSingleTable ::=
+ 'UNLOAD' 'SINGLE' 'TABLE' tableNames
+
+tableNames ::=
+ tableName (',' tableName)*
+
+tableName ::=
+ identifier
+```
+{{% /tab %}}
+{{% tab name="Railroad diagram" %}}
+<iframe frameborder="0" name="diagram" id="diagram" width="100%" height="100%"></iframe>
+{{% /tab %}}
+{{< /tabs >}}
+
+### Supplement
+
+- Unlike loading, only the table name needs to be specified when unloading a single table
+
+
+### Example
+
+- Unload specified single table
+
+```sql
+UNLOAD SINGLE TABLE t_single;
+```
+
+- Load all single tables
+
+```sql
+UNLOAD SINGLE TABLE *;
+-- or
+UNLOAD ALL SINGLE TABLES;
+```
+
+### Reserved word
+
+`UNLOAD`, `SINGLE`, `TABLE`, `ALL`, `TABLES`
+
+### Related links
+
+- [Reserved word](/en/user-manual/shardingsphere-proxy/distsql/syntax/reserved-word/)
diff --git a/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rql/rule-query/single-table/show-single-table.cn.md b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rql/rule-query/single-table/show-single-table.cn.md
index a2b415c081e..ba3d416c7b1 100644
--- a/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rql/rule-query/single-table/show-single-table.cn.md
+++ b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rql/rule-query/single-table/show-single-table.cn.md
@@ -33,10 +33,10 @@ databaseName ::=
### 返回值说明
-| 列 | 说明 |
-|---------------|------------|
-| table_name | 单表名称 |
-| resource_name | 单表所在的数据源名称 |
+| 列 | 说明 |
+|-------------------|-------------------|
+| table_name | 单表名称 |
+| storage_unit_name | 单表所在的数据源名称 |
### 示例
@@ -65,11 +65,11 @@ SHOW SINGLE TABLE t_user;
```sql
mysql> SHOW SINGLE TABLE t_user;
-+------------+---------------+
-| table_name | resource_name |
-+------------+---------------+
-| t_user | ds_0 |
-+------------+---------------+
++------------+-------------------+
+| table_name | storage_unit_name |
++------------+-------------------+
+| t_user | ds_0 |
++------------+-------------------+
1 row in set (0.00 sec)
```
@@ -81,11 +81,11 @@ SHOW SINGLE TABLES FROM sharding_db;
```sql
mysql> SHOW SINGLE TABLES FROM sharding_db;
-+------------+---------------+
-| table_name | resource_name |
-+------------+---------------+
-| t_user | ds_0 |
-+------------+---------------+
++------------+-------------------+
+| table_name | storage_unit_name |
++------------+-------------------+
+| t_user | ds_0 |
++------------+-------------------+
1 row in set (0.00 sec)
```
@@ -97,11 +97,11 @@ SHOW SINGLE TABLES;
```sql
mysql> SHOW SINGLE TABLES;
-+------------+---------------+
-| table_name | resource_name |
-+------------+---------------+
-| t_user | ds_0 |
-+------------+---------------+
++------------+-------------------+
+| table_name | storage_unit_name |
++------------+-------------------+
+| t_user | ds_0 |
++------------+-------------------+
1 row in set (0.00 sec)
```
diff --git a/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rql/rule-query/single-table/show-single-table.en.md b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rql/rule-query/single-table/show-single-table.en.md
index b638fdac774..454c36de5f2 100644
--- a/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rql/rule-query/single-table/show-single-table.en.md
+++ b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rql/rule-query/single-table/show-single-table.en.md
@@ -33,10 +33,10 @@ databaseName ::=
### Return value description
-| Column | Description |
-|---------------|-----------------------------------------------------|
-| table_name | Single table name |
-| resource_name | The resource name where the single table is located |
+| Column | Description |
+|-------------------|---------------------------------------------------------|
+| table_name | Single table name |
+| storage_unit_name | The storage unit name where the single table is located |
### Example
@@ -49,11 +49,11 @@ SHOW SINGLE TABLE t_user FROM sharding_db;
```sql
mysql> SHOW SINGLE TABLE t_user FROM sharding_db;
-+------------+---------------+
-| table_name | resource_name |
-+------------+---------------+
-| t_user | ds_0 |
-+------------+---------------+
++------------+-------------------+
+| table_name | storage_unit_name |
++------------+-------------------+
+| t_user | ds_0 |
++------------+-------------------+
1 row in set (0.00 sec)
```
@@ -65,11 +65,11 @@ SHOW SINGLE TABLE t_user;
```sql
mysql> SHOW SINGLE TABLE t_user;
-+------------+---------------+
-| table_name | resource_name |
-+------------+---------------+
-| t_user | ds_0 |
-+------------+---------------+
++------------+-------------------+
+| table_name | storage_unit_name |
++------------+-------------------+
+| t_user | ds_0 |
++------------+-------------------+
1 row in set (0.00 sec)
```
@@ -81,11 +81,11 @@ SHOW SINGLE TABLES FROM sharding_db;
```sql
mysql> SHOW SINGLE TABLES FROM sharding_db;
-+------------+---------------+
-| table_name | resource_name |
-+------------+---------------+
-| t_user | ds_0 |
-+------------+---------------+
++------------+-------------------+
+| table_name | storage_unit_name |
++------------+-------------------+
+| t_user | ds_0 |
++------------+-------------------+
1 row in set (0.00 sec)
```
@@ -97,11 +97,11 @@ SHOW SINGLE TABLES;
```sql
mysql> SHOW SINGLE TABLES;
-+------------+---------------+
-| table_name | resource_name |
-+------------+---------------+
-| t_user | ds_0 |
-+------------+---------------+
++------------+-------------------+
+| table_name | storage_unit_name |
++------------+-------------------+
+| t_user | ds_0 |
++------------+-------------------+
1 row in set (0.00 sec)
```
diff --git a/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rql/rule-query/single-table/show-unloaded-single-tables.cn.md b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rql/rule-query/single-table/show-unloaded-single-tables.cn.md
new file mode 100644
index 00000000000..c0c55b55e41
--- /dev/null
+++ b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rql/rule-query/single-table/show-unloaded-single-tables.cn.md
@@ -0,0 +1,57 @@
++++
+title = "SHOW UNLOADED SINGLE TABLES"
+weight = 4
++++
+
+### 描述
+
+`SHOW UNLOADED SINGLE TABLES` 语法用于查询未加载的单表。
+
+### 语法
+
+{{< tabs >}}
+{{% tab name="Grammar" %}}
+```sql
+showUnloadedSingleTables::=
+ 'SHOW' 'UNLOADED' 'SINGLE' 'TABLES'
+```
+{{% /tab %}}
+{{% tab name="Railroad diagram" %}}
+<iframe frameborder="0" name="diagram" id="diagram" width="100%" height="100%"></iframe>
+{{% /tab %}}
+{{< /tabs >}}
+
+### 返回值说明
+
+| 列 | 说明 |
+|-------------------|---------------------|
+| table_name | 单表名称 |
+| storage_unit_name | 单表所在的存储单元名称 |
+
+
+### 示例
+
+- 查询未加载的单表
+
+```sql
+SHOW UNLOADED SINGLE TABLES;
+```
+
+```sql
+mysql> SHOW UNLOADED SINGLE TABLES;
++------------+-------------------+
+| table_name | storage_unit_name |
++------------+-------------------+
+| t_single | ds_1 |
++------------+-------------------+
+1 row in set (0.01 sec)
+```
+
+### 保留字
+
+`SHOW`、`UNLOADED`、`SINGLE`、`TABLES`
+
+### 相关链接
+
+- [保留字](/cn/user-manual/shardingsphere-proxy/distsql/syntax/reserved-word/)
+
diff --git a/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rql/rule-query/single-table/show-unloaded-single-tables.en.md b/docs/document/content/user-manual/shardingsphere-proxy/distsql/syntax/rql/rule-query/single-table/show-unloaded-single-tables.en.md
new file mode 100644
index 00000000000..9dbdd009803
--- /dev/null
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+title = "SHOW UNLOADED SINGLE TABLES"
+weight = 4
++++
+
+### Description
+
+The `SHOW UNLOADED SINGLE TABLES` syntax is used to query unloaded single tables.
+
+### Syntax
+
+{{< tabs >}}
+{{% tab name="Grammar" %}}
+```sql
+showUnloadedSingleTables::=
+ 'SHOW' 'UNLOADED' 'SINGLE' 'TABLES'
+```
+{{% /tab %}}
+{{% tab name="Railroad diagram" %}}
+<iframe frameborder="0" name="diagram" id="diagram" width="100%" height="100%"></iframe>
+{{% /tab %}}
+{{< /tabs >}}
+
+### Return value description
+
+| Column | Description |
+|-------------------|---------------------------------------------------------|
+| table_name | Single table name |
+| storage_unit_name | The storage unit name where the single table is located |
+
+
+### Example
+
+- Query unloaded single tables.
+
+```sql
+SHOW UNLOADED SINGLE TABLES;
+```
+
+```sql
+mysql> SHOW UNLOADED SINGLE TABLES;
++------------+-------------------+
+| table_name | storage_unit_name |
++------------+-------------------+
+| t_single | ds_1 |
++------------+-------------------+
+1 row in set (0.01 sec)
+```
+
+### Reserved word
+
+`SHOW`, `UNLOADED`, `SINGLE`, `TABLES`
+
+### Related links
+
+- [Reserved word](/en/user-manual/shardingsphere-proxy/distsql/syntax/reserved-word/)