add alter datatype from 2082 to timecho (#1013)

Author: leto-b

src/UserGuide/Master/Table/Basic-Concept/Table-Management_timecho.md

@@ -259,7 +259,7 @@ Total line number = 1
 
 ### 1.5 Update Tables
 
-Used to update a table, including adding or deleting columns and configuring table properties.
+Used to update a table, including adding or deleting columns, modify column type (V2.0.8.2) and configuring table properties.
 
 **Syntax:**
 
@@ -273,13 +273,19 @@ ALTER TABLE (IF EXISTS)? tableName=qualifiedName ADD COLUMN (IF NOT EXISTS)? col
 | ALTER TABLE (IF EXISTS)? tableName=qualifiedName SET PROPERTIES propertyAssignments;                
 | COMMENT ON TABLE tableName=qualifiedName IS 'table_comment';
 | COMMENT ON COLUMN tableName.column IS 'column_comment';
+#changeColumndatatype;
+| ALTER TABLE (IF EXISTS)? tableName=qualifiedName ALTER COLUMN (IF EXISTS)? column=identifier SET DATA TYPE new_type=type;   
 ```
 
 **Note:：**
 
 1. The `SET PROPERTIES` operation currently only supports configuring the `TTL` property of a table
 2. The delete column function only supports deleting the ATTRIBUTE and FILD columns, and the TAG column does not support deletion.
 3. The modified comment will overwrite the original comment. If null is specified, the previous comment will be erased.
+4. Since version V2.0.8.2, modifying the data type of a column is supported. Currently, only columns with Category type FIELD can be modified.
+
+   * If the time series is concurrently deleted during the modification process, an error will be reported.
+   * The new data type must be compatible with the original type. The specific compatibility is shown in the following table:
 
 **Example:** 
 
@@ -289,6 +295,7 @@ ALTER TABLE table1 ADD COLUMN IF NOT EXISTS b FLOAT FIELD COMMENT 'b';
 ALTER TABLE table1 set properties TTL=3600;
 COMMENT ON TABLE table1 IS 'table1';
 COMMENT ON COLUMN table1.a IS null;
+ALTER TABLE table1 ALTER COLUMN IF EXISTS b SET DATA TYPE DOUBLE;
 ```
 
 ### 1.6 Delete Tables

src/UserGuide/Master/Table/SQL-Manual/SQL-Metadata-Operations_timecho.md

@@ -341,6 +341,8 @@ ALTER TABLE (IF EXISTS)? tableName=qualifiedName ADD COLUMN (IF NOT EXISTS)? col
 | ALTER TABLE (IF EXISTS)? tableName=qualifiedName SET PROPERTIES propertyAssignments;                
 | COMMENT ON TABLE tableName=qualifiedName IS 'table_comment';
 | COMMENT ON COLUMN tableName.column IS 'column_comment';
+#changeColumndatatype;
+| ALTER TABLE (IF EXISTS)? tableName=qualifiedName ALTER COLUMN (IF EXISTS)? column=identifier SET DATA TYPE new_type=type;
 ```
 
 **Examples:**
@@ -351,6 +353,7 @@ ALTER TABLE table1 ADD COLUMN IF NOT EXISTS b FLOAT FIELD COMMENT 'b';
 ALTER TABLE table1 set properties TTL=3600;
 COMMENT ON TABLE table1 IS 'table1';
 COMMENT ON COLUMN table1.a IS null;
+ALTER TABLE table1 ALTER COLUMN IF EXISTS b SET DATA TYPE DOUBLE;
 ```
 
 ### 2.6 Drop Table

src/UserGuide/Master/Table/User-Manual/Tree-to-Table_timecho.md

@@ -161,7 +161,7 @@ AS root.db.**
 ### 2.2 Modifying a Table View
 #### 2.2.1 Syntax Definition
 
-The ALTER VIEW function supports modifying the view name, adding columns, renaming columns, deleting columns, setting the view's TTL property, and adding comments via COMMENT.
+The ALTER VIEW function supports modifying the view name, adding columns, renaming columns, modifying FIELD column data type (supported since V2.0.8), deleting columns, setting the view's TTL property, and adding comments via COMMENT.
 
 ```SQL
 -- Rename view
@@ -176,6 +176,9 @@ viewColumnDefinition
 -- Rename a column in the view
 ALTER VIEW [IF EXISTS] viewName RENAME COLUMN [IF EXISTS] oldName TO newName
 
+-- Modify the data type of a FIELD column
+ALTER VIEW [IF EXISTS] viewName ALTER COLUMN [IF EXISTS] columnName SET DATA TYPE new_type
+
 -- Delete a column from the view
 ALTER VIEW [IF EXISTS] viewName DROP COLUMN [IF EXISTS] columnName
 
@@ -191,6 +194,21 @@ COMMENT ON COLUMN qualifiedName '.' column=identifier IS (string | NULL) #commen
 1. The `SET PROPERTIES`operation currently only supports configuring the TTL property for the table view.
 2. The `DROP COLUMN`function only supports deleting FIELD columns; TAG columns cannot be deleted.
 3. Modifying the comment will overwrite the original comment. If set to `null`, the previous comment will be erased.
+4. When modifying the data type of a FIELD column, the new data type must be compatible with the original type. The specific compatibility is shown in the following table:
+
+| Original Type | Convertible To Type                          |
+|---------------|----------------------------------------------|
+| INT32         | INT64, FLOAT, DOUBLE, TIMESTAMP, STRING, TEXT |
+| INT64         | TIMESTAMP, DOUBLE, STRING, TEXT             |
+| FLOAT         | DOUBLE, STRING, TEXT                        |
+| DOUBLE        | STRING, TEXT                                |
+| BOOLEAN       | STRING, TEXT                                |
+| TEXT          | BLOB, STRING                                |
+| STRING        | TEXT, BLOB                                  |
+| BLOB          | STRING, TEXT                                |
+| DATE          | STRING, TEXT                                |
+| TIMESTAMP     | INT64, DOUBLE, STRING, TEXT                 |
+
 #### 2.2.3 Usage Examples
 
 ```SQL
@@ -203,6 +221,9 @@ ALTER VIEW IF EXISTS tableview ADD COLUMN IF NOT EXISTS temperature float field
 -- Rename a column in the view
 ALTER VIEW IF EXISTS tableview RENAME COLUMN IF EXISTS temperature TO temp
 
+-- Modify the data type of a FIELD column
+ALTER VIEW IF EXISTS tableview ALTER COLUMN IF EXISTS temperature SET DATA TYPE double
+
 -- Delete a column from the view
 ALTER VIEW IF EXISTS tableview DROP COLUMN IF EXISTS temp
 

src/UserGuide/Master/Tree/Basic-Concept/Operate-Metadata_timecho.md

@@ -421,7 +421,43 @@ You can set different datatype, encoding, and compression for the timeseries in
 
 It is also supported to set an alias, tag, and attribute for aligned timeseries.
 
-### 2.3 Modifying Timeseries Name
+
+### 2.3 Modifying Timseries Data Types
+
+Starting from version V2.0.8, modifying the data type of a timeseries via SQL statements is supported.
+
+Syntax definition:
+
+```SQL
+ALTER TIMESERIES fullPath SET DATA TYPE newType=type
+```
+
+Notes:
+
+* If the timeseries is concurrently deleted during the modification process, an error will be reported.
+
+* The new data type must be compatible with the original type. The specific compatibility is shown in the following table:
+
+| Original Type  |Convertible To Type                                  |
+| ----------- | ----------------------------------------------- |
+| INT32     | INT64, FLOAT, DOUBLE, TIMESTAMP, STRING, TEXT |
+| INT64     | TIMESTAMP, DOUBLE, STRING, TEXT               |
+| FLOAT     | DOUBLE, STRING, TEXT                          |
+| DOUBLE    | STRING, TEXT                                  |
+| BOOLEAN   | STRING, TEXT                                  |
+| TEXT      | BLOB, STRING                                  |
+| STRING    | TEXT, BLOB                                    |
+| BLOB      | STRING, TEXT                                  |
+| DATE      | STRING, TEXT                                  |
+| TIMESTAMP | INT64, DOUBLE, STRING, TEXT                   |
+
+Usage example:
+
+```SQL
+ALTER TIMESERIES root.ln.wf01.wt01.temperature set data type DOUBLE
+```
+
+### 2.4 Modifying Timeseries Name
 
 Since version V2.0.8, it has been supported to modify the full path name of a timeseries through SQL statements. After a successful modification, the original name becomes invalid but is still retained in the metadata storage.
 
@@ -446,7 +482,7 @@ ALTER TIMESERIES root.ln.wf01.wt01.temperature RENAME TO root.newln.newwf.newwt.
 ```
 
 
-### 2.4 Delete Timeseries
+### 2.5 Delete Timeseries
 
 To delete the timeseries we created before, we are able to use `(DELETE | DROP) TimeSeries <PathPattern>` statement.
 
@@ -459,7 +495,7 @@ delete timeseries root.ln.wf02.*;
 drop timeseries root.ln.wf02.*;
 ```
 
-### 2.5 Show Timeseries
+### 2.6 Show Timeseries
 
 * SHOW LATEST? TIMESERIES pathPattern? whereClause? limitClause?
 
@@ -618,7 +654,7 @@ IoTDB> show invalid timeSeries
 Explanation: The last column, "NewPath," in the returned result displays the new sequence corresponding to the invalidated sequence. This serves scenarios such as view construction and cluster migration (Load + rename).
 
 
-### 2.6 Count Timeseries
+### 2.7 Count Timeseries
 
 IoTDB is able to use `COUNT TIMESERIES <Path>` to count the number of timeseries matching the path. SQL statements are as follows:
 
@@ -703,7 +739,7 @@ It costs 0.002s
 
 > Note: The path of timeseries is just a filter condition, which has no relationship with the definition of level.
 
-### 2.7 Active Timeseries Query
+### 2.8 Active Timeseries Query
 By adding WHERE time filter conditions to the existing SHOW/COUNT TIMESERIES, we can obtain time series with data within the specified time range.
 
 It is important to note that in metadata queries with time filters, views are not considered; only the time series actually stored in the TsFile are taken into account.
@@ -743,7 +779,7 @@ count timeseries where time >= 15000 and time < 16000;
 +-----------------+
 ```
 Regarding the definition of active time series, data that can be queried normally is considered active, meaning time series that have been inserted but deleted are not included.
-### 2.8 Tag and Attribute Management
+### 2.9 Tag and Attribute Management
 
 We can also add an alias, extra tag and attribute information while creating one timeseries.
 

src/UserGuide/Master/Tree/SQL-Manual/Keywords.md

@@ -208,6 +208,7 @@
 - TRIGGER
 - TRIGGERS
 - TTL
+- TYPE
 - UNLINK
 - UNLOAD
 - UNSET

src/UserGuide/Master/Tree/SQL-Manual/SQL-Manual_timecho.md

@@ -142,15 +142,21 @@ error: encoding TS_2DIFF does not support BOOLEAN
 CREATE ALIGNED TIMESERIES root.ln.wf01.GPS(latitude FLOAT , longitude FLOAT);
 ```
 
-### 2.3 Modify Timeseries Name
+### 2.3 Modify Timeseries Data Type
+> Supported since V2.0.8
 
+```SQL
+ALTER TIMESERIES root.ln.wf01.wt01.temperature set data type DOUBLE
+```
+
+### 2.4 Modify Timeseries Name
 > This statement is supported from V2.0.8 onwards
 
 ```sql
 ALTER TIMESERIES root.ln.wf01.wt01.temperature RENAME TO root.newln.newwf.newwt.temperature
 ```
 
-### 2.4 Delete Timeseries
+### 2.5 Delete Timeseries
 
 ```sql
 delete timeseries root.ln.wf01.wt01.status;
@@ -159,7 +165,7 @@ delete timeseries root.ln.wf02.*;
 drop timeseries root.ln.wf02.*;
 ```
 
-### 2.5 Show Timeseries
+### 2.6 Show Timeseries
 
 ```sql
 show timeseries root.**;
@@ -172,7 +178,7 @@ show latest timeseries;
 show invalid timeseries; -- This statement is supported from V2.0.8.2 onwards;
 ```
 
-### 2.6 Count Timeseries
+### 2.7 Count Timeseries
 
 ```sql
 COUNT TIMESERIES root.**;
@@ -189,7 +195,7 @@ COUNT TIMESERIES root.ln.** GROUP BY LEVEL=2;
 COUNT TIMESERIES root.ln.wf01.* GROUP BY LEVEL=2;
 ```
 
-### 2.7 Tag and Attribute Management
+### 2.8 Tag and Attribute Management
 
 ```sql
 create timeseries root.turbine.d1.s1(temprature) with datatype=FLOAT tags(tag1=v1, tag2=v2) attributes(attr1=v1, attr2=v2);

src/UserGuide/latest-Table/Basic-Concept/Table-Management_timecho.md

@@ -259,7 +259,7 @@ Total line number = 1
 
 ### 1.5 Update Tables
 
-Used to update a table, including adding or deleting columns and configuring table properties.
+Used to update a table, including adding or deleting columns, modify column type (V2.0.8.2) and configuring table properties.
 
 **Syntax:**
 
@@ -273,13 +273,19 @@ ALTER TABLE (IF EXISTS)? tableName=qualifiedName ADD COLUMN (IF NOT EXISTS)? col
 | ALTER TABLE (IF EXISTS)? tableName=qualifiedName SET PROPERTIES propertyAssignments;                
 | COMMENT ON TABLE tableName=qualifiedName IS 'table_comment';
 | COMMENT ON COLUMN tableName.column IS 'column_comment';
+#changeColumndatatype;
+| ALTER TABLE (IF EXISTS)? tableName=qualifiedName ALTER COLUMN (IF EXISTS)? column=identifier SET DATA TYPE new_type=type;
 ```
 
 **Note:：**
 
 1. The `SET PROPERTIES` operation currently only supports configuring the `TTL` property of a table
 2. The delete column function only supports deleting the ATTRIBUTE and FILD columns, and the TAG column does not support deletion.
 3. The modified comment will overwrite the original comment. If null is specified, the previous comment will be erased.
+4. Since version V2.0.8.2, modifying the data type of a column is supported. Currently, only columns with Category type FIELD can be modified.
+
+   * If the time series is concurrently deleted during the modification process, an error will be reported.
+   * The new data type must be compatible with the original type. The specific compatibility is shown in the following table:
 
 **Example:** 
 
@@ -289,6 +295,7 @@ ALTER TABLE table1 ADD COLUMN IF NOT EXISTS b FLOAT FIELD COMMENT 'b';
 ALTER TABLE table1 set properties TTL=3600;
 COMMENT ON TABLE table1 IS 'table1';
 COMMENT ON COLUMN table1.a IS null;
+ALTER TABLE table1 ALTER COLUMN IF EXISTS b SET DATA TYPE DOUBLE;
 ```
 
 ### 1.6 Delete Tables

src/UserGuide/latest-Table/SQL-Manual/SQL-Metadata-Operations_timecho.md

@@ -341,6 +341,8 @@ ALTER TABLE (IF EXISTS)? tableName=qualifiedName ADD COLUMN (IF NOT EXISTS)? col
 | ALTER TABLE (IF EXISTS)? tableName=qualifiedName SET PROPERTIES propertyAssignments;                
 | COMMENT ON TABLE tableName=qualifiedName IS 'table_comment';
 | COMMENT ON COLUMN tableName.column IS 'column_comment';
+#changeColumndatatype;
+| ALTER TABLE (IF EXISTS)? tableName=qualifiedName ALTER COLUMN (IF EXISTS)? column=identifier SET DATA TYPE new_type=type;
 ```
 
 **Examples:**
@@ -351,6 +353,7 @@ ALTER TABLE table1 ADD COLUMN IF NOT EXISTS b FLOAT FIELD COMMENT 'b';
 ALTER TABLE table1 set properties TTL=3600;
 COMMENT ON TABLE table1 IS 'table1';
 COMMENT ON COLUMN table1.a IS null;
+ALTER TABLE table1 ALTER COLUMN IF EXISTS b SET DATA TYPE DOUBLE;
 ```
 
 ### 2.6 Drop Table

src/UserGuide/latest-Table/User-Manual/Tree-to-Table_timecho.md

@@ -161,7 +161,7 @@ AS root.db.**
 ### 2.2 Modifying a Table View
 #### 2.2.1 Syntax Definition
 
-The ALTER VIEW function supports modifying the view name, adding columns, renaming columns, deleting columns, setting the view's TTL property, and adding comments via COMMENT.
+The ALTER VIEW function supports modifying the view name, adding columns, renaming columns, modifying FIELD column data type (supported since V2.0.8), deleting columns, setting the view's TTL property, and adding comments via COMMENT.
 
 ```SQL
 -- Rename view
@@ -176,6 +176,9 @@ viewColumnDefinition
 -- Rename a column in the view
 ALTER VIEW [IF EXISTS] viewName RENAME COLUMN [IF EXISTS] oldName TO newName
 
+-- Modify the data type of a FIELD column
+ALTER VIEW [IF EXISTS] viewName ALTER COLUMN [IF EXISTS] columnName SET DATA TYPE new_type
+
 -- Delete a column from the view
 ALTER VIEW [IF EXISTS] viewName DROP COLUMN [IF EXISTS] columnName
 
@@ -191,6 +194,21 @@ COMMENT ON COLUMN qualifiedName '.' column=identifier IS (string | NULL) #commen
 1. The `SET PROPERTIES`operation currently only supports configuring the TTL property for the table view.
 2. The `DROP COLUMN`function only supports deleting FIELD columns; TAG columns cannot be deleted.
 3. Modifying the comment will overwrite the original comment. If set to `null`, the previous comment will be erased.
+4. When modifying the data type of a FIELD column, the new data type must be compatible with the original type. The specific compatibility is shown in the following table:
+
+| Original Type | Convertible To Type                          |
+|---------------|----------------------------------------------|
+| INT32         | INT64, FLOAT, DOUBLE, TIMESTAMP, STRING, TEXT |
+| INT64         | TIMESTAMP, DOUBLE, STRING, TEXT             |
+| FLOAT         | DOUBLE, STRING, TEXT                        |
+| DOUBLE        | STRING, TEXT                                |
+| BOOLEAN       | STRING, TEXT                                |
+| TEXT          | BLOB, STRING                                |
+| STRING        | TEXT, BLOB                                  |
+| BLOB          | STRING, TEXT                                |
+| DATE          | STRING, TEXT                                |
+| TIMESTAMP     | INT64, DOUBLE, STRING, TEXT                 |
+
 #### 2.2.3 Usage Examples
 
 ```SQL
@@ -203,6 +221,9 @@ ALTER VIEW IF EXISTS tableview ADD COLUMN IF NOT EXISTS temperature float field
 -- Rename a column in the view
 ALTER VIEW IF EXISTS tableview RENAME COLUMN IF EXISTS temperature TO temp
 
+-- Modify the data type of a FIELD column
+ALTER VIEW IF EXISTS tableview ALTER COLUMN IF EXISTS temperature SET DATA TYPE double
+
 -- Delete a column from the view
 ALTER VIEW IF EXISTS tableview DROP COLUMN IF EXISTS temp