tsdb

In https://github.com/taosdata/TDengine/blob/develop/src/client/src/tscPrepare.c, Local variable loopCont is assigned only once, to a constant value, making it effectively constant throughout its scope. If this is not the intent, examine the logic to see if there is a missing assignment that would make loopCont not remain constant.

So the 1567th line should be removed.
![image](https://user-im

Describe the Bug

The JSON response sent back over HTTP doesn't encode certain characters correctly.

For example, if a value in a string column contains the char \1 the byte value is copied verbatim in the response, breaking the client:

>>> json.loads('"\1"')
...
json.decoder.JSONDecodeError: Invalid control character at: line 1 column 2 (char 1)

Instead, we shou