[GitHub] [iotdb] SteveYurongSu commented on a change in pull request #1914: [IOTDB-937] change jdbc into session and don't need to create metadata

[GitBox <gi...@apache.org>]

SteveYurongSu commented on a change in pull request #1914:
URL: https://github.com/apache/iotdb/pull/1914#discussion_r519416781



##########
File path: README.md
##########
@@ -347,14 +348,17 @@ CREATE TIMESERIES root.fit.d2.s3 WITH DATATYPE=INT32,ENCODING=RLE;
 CREATE TIMESERIES root.fit.p.s1 WITH DATATYPE=INT32,ENCODING=RLE;
 ```
 
+> if you didn't create metadata in the IoTDB in another computer, IoTDB will infer datatype by itself and this probably caused time series has different datatype and many other unexpected things.

Review comment:
       ```suggestion
   IoTDB has the ability of type inference, so it is not necessary to create metadata before data import. However, we still recommend creating metadata before importing data using the CSV import tool, as this can avoid unnecessary type conversion errors.
   ```

##########
File path: README.md
##########
@@ -347,14 +348,17 @@ CREATE TIMESERIES root.fit.d2.s3 WITH DATATYPE=INT32,ENCODING=RLE;
 CREATE TIMESERIES root.fit.p.s1 WITH DATATYPE=INT32,ENCODING=RLE;
 ```
 
+> if you didn't create metadata in the IoTDB in another computer, IoTDB will infer datatype by itself and this probably caused time series has different datatype and many other unexpected things.
+
 ### An example of import csv file
 
 ```
 Time,root.fit.d1.s1,root.fit.d1.s2,root.fit.d2.s1,root.fit.d2.s3,root.fit.p.s1
-1,100,'hello',200,300,400
-2,500,'world',600,700,800
-3,900,'IoTDB',1000,1100,1200
+1,100,hello,200,300,400
+2,500,world,600,700,800
+3,900,IoTDB,1000,1100,1200

Review comment:
       ```suggestion
   3,900,"hello, world",1000,1100,1200
   ```

##########
File path: README.md
##########
@@ -347,14 +348,17 @@ CREATE TIMESERIES root.fit.d2.s3 WITH DATATYPE=INT32,ENCODING=RLE;
 CREATE TIMESERIES root.fit.p.s1 WITH DATATYPE=INT32,ENCODING=RLE;
 ```
 
+> if you didn't create metadata in the IoTDB in another computer, IoTDB will infer datatype by itself and this probably caused time series has different datatype and many other unexpected things.
+
 ### An example of import csv file
 
 ```
 Time,root.fit.d1.s1,root.fit.d1.s2,root.fit.d2.s1,root.fit.d2.s3,root.fit.p.s1
-1,100,'hello',200,300,400
-2,500,'world',600,700,800
-3,900,'IoTDB',1000,1100,1200
+1,100,hello,200,300,400
+2,500,world,600,700,800
+3,900,IoTDB,1000,1100,1200
 ```
+> if you have a comma in your field, the field should be enclosed by a double quote or single quote.

Review comment:
       As a user, I may have the following concerns:
   
   1. What delimiters are allowed?
   2. What are the special characters (e.g., `"` and `,`) that will affect data import? How should these special characters be handled?
   
   I think the documentation is not clear enough.

##########
File path: README_ZH.md
##########
@@ -347,16 +347,19 @@ CREATE TIMESERIES root.fit.d2.s1 WITH DATATYPE=INT32,ENCODING=RLE;
 CREATE TIMESERIES root.fit.d2.s3 WITH DATATYPE=INT32,ENCODING=RLE;
 CREATE TIMESERIES root.fit.p.s1 WITH DATATYPE=INT32,ENCODING=RLE;
 ```
+> 如果您没有在另一台计算机的IoTDB中创建元数据，IoTDB将自己推断数据类型，这可能会导致时间序列具有不同的数据类型和许多其他意想不到的东西。

Review comment:
       ```suggestion
   IoTDB具有类型推断的能力，因此在数据导入前创建元数据不是必须的。但我们仍然推荐在使用CSV导入工具导入数据前创建元数据，因为这可以避免不必要的类型转换错误。
   ```




----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

For queries about this service, please contact Infrastructure at:
users@infra.apache.org